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The Marine Conservation Society

Basking Shark Watch

20-year report (1987-2006)

Sally Sharrock

Angus Bloomfield and Jean-Luc Solandt

Overross House, Ross Park, Ross-on-Wye, Herefordshire, HR9 7US01989 566 017 www.mcsuk.org [email protected] charity # : 1004005

http://www.mcsuk.org/

mailto:[email protected]

Acknowledgments This report would not have been possible without the support of the hundreds of individuals and organisations who have reported their basking shark sightings. Too numerous to mention individually, MCS would like to extend a heartfelt thankyou to all those who have contributed their valuable time to recording and sending MCS reports of their sightings of basking sharks over the past 20+ years, ensuring that the project has been successful in reaching many conservation gains for the species. MCS would like to express its thanks to the following organisations and individuals that have contributed data and / or advice to Basking Shark Watch: Biscay Dolphin Research Group; Centre for Environmental Data and Recording Northern Ireland; Colin Speedie; Countryside Council for Wales; Devon Biodiversity Records Centre; Environment Agency; Environment and Heritage Service Northern Ireland; Environmental Records Centre for Cornwall and the Isles of Scilly; Hebridean Whale and Dolphin Trust; Irish Whale and Dolphin Group; Joint Nature Conservation Committee; Manx Basking Shark Watch; Manx Wildlife Trust; Marine Biological Association; MarLIN; Millport Marine Lab; National Parks and Wildlife Service (Ireland); Sea Mammal Research Unit, SeaTrust Foundation; Shark Trust; Shetland Local Records Centre; Solway Shark and Sea Mammal Survey; Royal National Lifeboat Institute; Royal Society for the Protection of Birds; The Wildlife Trusts. A special thank you must be made to Steve Frampton who generated many of the maps in this report. Finally, a thank you to the funders of Basking Shark Watch as part of the 2006-2008 Cool Seas Roadshow grant: Defra, Natural England (through the Biodiversity Action Fund Countdown 2010 award).

Marine Conservation Society Basking Shark Watch 20 year report 1987-2006 2

Contents Contents 3

List of Figures 5

1. Executive summary 7

2. Introduction 8 2.1 Taxonomy 8 2.2 Visible Diagnostics 8 2.3 Life History Characteristics 9

2.3.1 Reproduction 9 2.3.2 Feeding 9 2.3.3 Behaviour 10

2.4 Population Status 11 2.5 Distribution & Migration 12 2.6 Threats 14

2.6.1 Targeted Fisheries 14 2.6.2 Incidental Bycatch 16 2.6.3 Disturbance 17 2.6.4 Environmental Pressures 17

2.7 Current Protection and Management 18 2.7.1 National 19 2.7.2 International 20 2.7.3 Additional Protection Measures 24

2.8 Basking Shark Research & Sightings Projects 25 2.8.1 Conserving Endangered Basking Sharks Project (finished in 2006) 25 2.8.2 Defra, CEFAS & the MBA 25 2.8.3 European Basking Shark Photo identication Project (EBSPIP) 26 2.8.4 The Wildlife Trust Basking Shark Project 26 2.8.5 Save Our Sea Foundation Basking Shark research – Firth of Clyde 26 2.8.6 Isle of Man Basking Shark Watch Project 26 2.8.7 Irish Whale and Dolphin Group 27 2.8.8 Seawatch Southwest 27 2.8.9 APECS 27 2.8.10 Phenology of basking shark movement patterns 27

3. Methods 28 3.1 Project Background 28 3.2 Promotion 28 3.3 Recording Methods 28

3.3.1 Report Cards 28 3.3.2 Online (http://www.mcsuk.org) 28 3.3.3 Telephone 29


3.4 Limitations of Basking Shark Watch 29 3.4.1 Data Characteristics 29 3.4.2 Effort & Regional Bias 29 3.4.3 Multiple Sightings 30

3.5 Data Management & Collaboration 30

4. Results 32 4.1 Geographic Distribution 32 4.2 Regional Analysis 34

4.2.1 Southwest England and the Channel Islands 37 4.2.2 Scotland 40 4.2.3 Isle of Man 44 4.2.4 Comparing size class between regions 48

4.3 Shark size over time 49 4.3.1 Inter-annual variation 49

4.4 Shoal size 51

5.0 Discussion 52 5.1 Regional hotspots 52 5.2 Local hotspots 52

5.2.1 Southwest England 52 5.2.2 The Isle of Man 52 5.2.3 Scotland 52

5.3 Fronts 53 5.4 Causes and timing of surface ‘basking’ behaviour 53 5.5 Feeding 54 5.6 Social behaviour 55

6.0 Conservation 56 6.1 European 56 6.2 Site based protection (MPAs) 56 6.3 Management of threat 58

6.3.1 Pleasure boat craft 58 6.3.2 Static fishing gears 60 6.3.3 Mobile fishing gears 61

7.0 Recommendations 62

8.0 References 63


List of Figures Figure 1. Basking shark shoaling behaviour (copyright, Wilson 2004). ............11 Figure 2. Basking shark tracking work carried out by the Marine Biological

Association (left), and the Massachusetts Dept of Fisheries (right). ............21 Figure 3. Basking shark on sale in Bordeaux hypermarket, February 2005.....22 Figure 4. Distribution of basking shark sightings around the UK and Ireland,

1987-2006 (individual sightings are plotted as single red dots). ..................32 Figure 5. Distribution of basking shark sightings around the UK and Ireland,

1987-2006 (lightest shades are 1-10 sightings; then 11-50; 51-100; the darkest squares represent densities of 100+ sightings)...............................33

Figure 6. Total number of sighting reports received from each UK/local region between 1987-2006. ....................................................................................35

Figure 7. Percentage contribution of each region to total sighting reports, 1987-2006. ..........................................................................................................36

Figure 8. Total sighting reports per year, including regional origin. ..................36 Figure 9: Number of basking shark sightings (by 5km2 cell) from the southwest

region: Dorset, Devon, Cornwall and the Scillies, including the Channel Islands. ........................................................................................................37

Figure 10. Annual variation in numbers of sighting reports and shark numbers, received from SW England. .........................................................................38

Figure 11. Seasonal variation in numbers of sighting reports and shark numbers, received from SW England (1987-2006)......................................39

Figure 12. Size frequency of basking sharks reported from Southwest England, 1987-2006. ...................................................................................39

Figure 13: Number of basking shark sightings (by 5km2 cell) from Scottish waters. The map includes the 12nm limit of territorial seas. ........................40

Figure 14. Annual variation in sighting report and shark numbers, received from Scotland...............................................................................................41

Figure 15. Seasonal variation in sighting report and shark numbers, received from Scotland (1987-2006). .........................................................................42

Figure 16. Size frequency of basking sharks reported from Scotland between 1987-2006....................................................................................................43

Figure 17: Number of basking shark sightings (by 5km2 cell) from Irish Sea / Isle of Man waters. The map includes the 12nm limit of territorial seas.......44

Figure 18. Annual variation in sighting report and shark numbers, received from the Isle of Man. ....................................................................................45

Figure 19. Seasonal variation in sighting report and shark numbers, received from the Isle of Man (1987-2006).................................................................46

Figure 20. Size frequency of basking sharks reported from the Isle of Man between 1987-2006. ....................................................................................47

Figure 21. Shark size frequency in the different regions.................................48 Figure 22. Mean shark size per year, 1987-2006 (UK wide). .........................49 Figure 23. Mean shark size per year in SW England, 1987-2006...................49 Figure 24. Basking shark shoal sizes. (Black dots 10-49 sharks; Yellow dots

50-99 sharks; Red dots 100+ sharks). .........................................................51 Figure 25. Distribution of fronts (left) and basking shark hotspot locations

(right) from research carried out by the Marine Biological Association. (Source Sims et al, 2005). ...........................................................................53


Figure 26. The total number of surface sightings per month by the average monthly mean total copepod abundance and monthly mean SST from 1987-2005 in southwest England. (Source: Phenix, 2007). ..................................54

Figure 27. The total number of surface sightings per month by the average monthly mean total copepod abundance and monthly mean SST from 1987-2005 in Scotland. (Source: Phenix, 2007). ..................................................54

Figure 28. MCS recommendations for basking shark MPA in southwest England: Gwennap Head (southern Land’s End peninsula) and eastern Lizard peninsula...........................................................................................57

Figure 29. MCS recommendation for a basking shark MPA in the southwest Isle of Man at Niarbyl Bay. ...........................................................................57

Figure 30. MCS recommendation for a basking shark MPA off the west coast of Scotland at the Hyskeir lighthouse...........................................................58

Figure 31. Basking shark / RIB encounter recorded near Land’s End, Cornwall in 2006. This activity by the boat handlers clearly breaches the code of conduct recommendation, which states that engines should be switched to neutral up to 100m away from the sharks. (Photo by Rebecca Hoskin). .....59

Figure 32. Basking shark accidentally caught in pot ropes near Sennen Cove, Land’s End in June 2007. (photo by Andrew Carn) .....................................60

Figure 33. Typical lobster pot array showing the surface ropes for fishermen to relocate and haul the pots on board the vessel. It is the vertical ropes, and the loose surface horizontal flagged buoy ropes that commonly entangle sharks. (from Eno et al., 2001).....................................................................61

List of Tables Table 1. Regional breakdown of all sighting reports received by Basking Shark

Watch between 1987-2006. .........................................................................34 Table 2. Basking shark shoal sizes, and location............................................51


1. Executive summary Findings

• Basking shark surface distribution is clearly and repetitively identified from three hotspots around UK waters – the Southwest coast of England from the Isles of Scilly to Dorset; the Southwest coast of the Isle of Man; and Western Scotland.

• Southwest England has contributed the largest number of sightings (45%) followed by Scotland (33%), and the Isle of Man (13%).

• The number of basking shark sightings reported to the Marine Conservation Society has alternated between years, but the trend is one of increasing numbers, with the highest ever number reported in 2006 – 2275 sightings.

• Basking shark surface foraging appears to be linked to seasonal oceanographic conditions. Initially sharks are seen at the surface in southwest English waters in May; in Isle of Man waters in June; and in Scottish waters in June.

• Sea surface temperature appears to be the strongest influence to basking sharks first appearing at the different regional hotspots in surface waters, whilst the fall in copepod density below a particular threshold level coincides with the sharks moving offshore and to deeper waters.

• Basking shark mean size has increased over the 20 years of the project from a mean of ≈3.5m to ≈5.12m. The increase in recorded mean size range of animals may indicate the success of UK conservation measures for the species, (the shark was listed on the Wildlife and Countryside Act in 1998, which prevented it from being hunted in UK territorial waters).

Significant conservation achievements

• MCS, with the support of the Basking Shark Biodiversity Action Plan Steering Group, Defra and JNCC successfully compiled a proposal to have the shark listed on Annex I and II of the Convention on Migratory Species (Bonn Convention) in November 2005.

• The listing on the Bonn Convention led to the basking shark being listed on the Common Fisheries Policy regulations in January 2007, banning the capture, sale, and transhipment of the species in all EU waters by any EU or non EU-registered vessels. Similarly, all EU registered vessels are banned from landing the basking shark in waters outside European jurisdiction.

• MCS helped to facilitate the first UK workshop to discuss the location of protected areas for the species via the Finding Sanctuary MPA designation process (April 2008).

• MCS successfully collaborated with the Isle of Man government and Manx Wildlife Trust in 2005 to share information on sightings, behaviour and migration of the species.

• MCS campaigned to have the basking shark listed on the Wildlife and Countryside Act in 1998.

• MCS contributed to efforts which resulted in the basking shark being listed on CITES Appendix II in November 2002.

• MCS is joint lead partner for the basking shark Biodiversity Action Plan (since 2004). The basking shark BAP steering group has acted as symposia for research and conservation for the species in UK territorial waters and northern France, and resulted in direct action to get the species listed on the Convention on Migratory Species in 2005.

• MCS has contributed to the Conserving Endangered Basking Sharks project (2002-2006), which has helped identify hotspots for basking sharks.


2. Introduction The basking shark (Cetorhinus maximus) is the largest fish species in the Northeast Atlantic and the second largest in the world, growing in excess of 11 metres in length and weighing up to 7 tonnes. However, much of the basking shark’s life history, movements, population dynamics and general ecology have not been described. This lack of ecological data led the Marine Conservation Society (MCS) to launch the Basking Shark Watch project in 1987 as part of its campaign to protect the basking shark. Basking Shark Watch originally aimed to provide a general indication of the geographical distribution of basking shark surface sightings around the UK coast (Earll & Turner, 1992). The project involves members of the public and independent organisations recording details of their shark sightings and the subsequent collection and analysis of these records by MCS. The scheme’s aims are to:

• Maintain a database of information on relative abundance, distribution and behaviour of basking sharks in UK waters; • Collect and analyse sightings data to improve our knowledge of basking shark ecology, population dynamics and behaviour; • Support and progress the UK Basking Shark Species Action Plan, and extended protection measures in Northeast Atlantic waters; and; • Raise public awareness about basking sharks and the threats they face.

Sightings records are collected by MCS via pre-printed report cards, online facilities (www.mcsuk.org) and by telephone. This report aims to identify basking shark surface activity hotspots around the UK, determine annual and seasonal variations in numbers and distribution of basking shark sightings, and to regionally analyse distribution, size and behaviour of recorded basking sharks from 20 years (1987-2006). The report provides information that may be useful in the development of a more focused approach to the implementation of the Basking Shark Biodiversity Action Plan at national, regional and local levels. MCS works with the Shark Trust and the Wildlife Trust as a joint lead partner of the Basking Shark Species Action Plan (SAP). 2.1 Taxonomy Phylum Chordata Class Chondrichthyes Subclass Elasmobranchii Order Lamniformes Family Cetorhinidae Taxon Cetorhinus maximus (Gunnerus) Common Name Basking shark 2.2 Visible Diagnostics • Elongate and stout body. • Large size and extensive gill slits which virtually encircle the head. • Pinkish gill rakers often visible when viewed feeding at close range. • Prominent pointed snout. • Small eyes. • Large, hoop like mouth containing hundreds of minute and vestigial teeth. • Notched tail (caudal fin) and large, angular dorsal and pectoral fins. • Mottled grey/brown colouration.



2.3 Life History Characteristics 2.3.1 Reproduction Relatively little is known of the reproductive habits of the basking shark, but what is known is true for many lamnid sharks. Basking sharks are ovoviviparous, meaning that they give birth to live, well-developed young that hatch from eggs incubated inside the female (Compagno, 1984). Size at birth is suggested to be about 1.6m and the smallest recorded free-living individual was 1.65m (FAO, 2004). Males are thought to mature at 12-16 years of age (5-7m length). Females reach sexual maturity later at 18 years (8-9m length), and produce a litter of about 6 pups at intervals of between 2 to 4 years (Pauly, 2002). Gestation period is likely to be 12-36 months. Evidence suggests that longevity is approximately 50 years (Pauly, 1978; 2002; Compagno, 1984; Fowler, 1996). The life history of basking sharks is not at all well understood, providing great scope for further research from UK and international waters. Relative to other shark species, the basking shark matures very late and has slow growth rate, a long gestation period and low fecundity, making them extremely vulnerable to overfishing (Compagno, 1984). 2.3.2 Feeding The basking shark is one of three large, filter-feeding sharks, the other two being the megamouth (Megachasma pelagios) and the whaleshark (Rhincodon typus). Basking sharks feed by swimming forwards with a widely open mouth to capture particulate prey that are removed from passive water flow across the gill arches, a strategy known as ‘ram filter feeding’ (Sims, 1999). Basking sharks are selective foragers on zooplankton, feeding predominantly on energy rich calanoid copepods such as Calanus finmarchicus and C. helgolandicus. Travelling at a constant speed of 2 knots the basking shark could filter in excess of 2,000 tonnes of water per hour and on average 0.5 tonnes of material may be present in the stomach at any given time (FAO, 2004). The sharks concentrate their feeding effort along thermal fronts, where copepod abundance is high, and spend on average 27 hours travelling along them and feeding, before moving on to new areas of high prey density (Sims et al.,1997; Sims & Quayle, 1998; Sims et al., 2003a). This makes them good indicators of trends in abundance of zooplankton species, which in turn are influenced by climatic fluctuations of the North Atlantic Oscillation (NAO) (Sims & Quayle, 1998). The basking shark is the only known ‘ram filter-feeding’ shark. Similar species, the whaleshark and megamouth, produce a vacuum through suction to facilitate feeding. In order to meet their energy requirements for such active feeding techniques, basking sharks must select and remain in areas of high plankton concentrations, otherwise they would be feeding at an energetic loss (Parker & Boeseman, 1954; Sims, 1999). Basking sharks have been shown to alter their foraging behaviour according to the abundance of zooplankton and exhibit ‘area restricted searching’ whereby they follow convoluted swimming patterns and spend considerably longer periods of time in areas where zooplankton abundance is greatest (Sims & Quayle, 1998; Sims et al., 2000 a). Sims (1999) showed that basking sharks can feed and survive on plankton densities far lower than previously thought and calculated a threshold density for basking shark feeding of 0.62 gm-3, equivalent to about 400 copepods m3. Zooplankton abundance in the Northeast Atlantic is generally lower during the winter than summer, but the copepod concentration measured in Plymouth waters (where Sims’ study took place) in winter was above this threshold density for shark feeding, suggesting that basking sharks may not be limited to feeding solely in the summer (Sims, 1999).

Basking sharks follow their prey both horizontally and vertically. They are known to forage over vast distances (Sims et. al. 2005) to source their prey. The data from satellite tags fixed to basking sharks by MBA researchers in 2001 also revealed that sharks undertake extensive vertical migrations to feed on plankton located at different


stratified layers (Sims et al., 2005). Sharks exhibited normal Diel Vertical Migration (DVM) in stratified deep offshore waters (dusk-ascent; dawn-descent); however in shallow coastal nearshore waters, where thermal fronts occur, the reverse pattern was witnessed, with sharks ascending at dawn and descending at dusk (Sims et al., 2003b and 2006). It was postulated that these patterns were as a result of the distribution of predatory plankton (principally sagitta spp.), which are known to need light to feed on calanus copepods – as such copepods in stratified water only forage in shallow waters on zooplankton in darkness to avoid being captured by predatory plankton. Sims postulated that the mixing of waters at frontal areas essentially reversed this process, leading to copepods being in surface waters in the day, and thereby attracting surface forarging sharks. Similar patterns of vertical migration were observed in the Pacific Ocean with the megamouth shark Megachasma pelagios (Nelson et al., 1997) migrating vertically to surface waters at dusk, and descending to deeper waters at dawn. 2.3.3 Behaviour Basking sharks are most often observed at or near the surface, singly, in pairs, triads or in shoals numbering a hundred or more. Commonly, the dorsal and caudal fin and snout protrude above the sea surface while the shark swims in slow feeding circles with its mouth open. When feeding, basking sharks are thought to be solitary, however they also form loose aggregations when individuals feed on the same discrete patches of plankton (Sims & Quayle, 1998). Sharks will actively avoid each other when foraging in patches. Social behaviour consisting of organized and synchronised swimming has rarely been observed or studied, but ‘close-following’ (social) behaviour has been recorded for sharks between 5 and 8m length during summer in Southwest England (Sims et al., 2000 a), and the Isle of Man (Galpin, pers comm.). This is thought to be courtship-related behaviour (Sims et al., 2000 a) and previous studies suggest that basking sharks mate during summer (Matthews, 1950). ‘Close-following’ behaviour includes ‘nose-to-tail following’ (0-0.5 body lengths behind), ‘close-flank approach’, ‘parallel swimming’, and ‘echelon swimming’ (when two or more sharks follow a lead individual) and has been observed to last between 1.8 and 5.8 hours. During one study ‘close-following’ was most commonly observed between pairs of sharks and between three and four individuals (Sims et al., 2000 b). Observations of schools up to 50 basking sharks were made on the warm side of a persistent thermal front in the Southern Gulf of Maine between September and mid October 2002 (Wilson, 2004). Aerial photography showed ‘cartwheel formation schooling’, where the group rotated like a spinning wheel, and ‘milling behaviour’, whereby sharks were less synchronised in their following behaviours (Fig. 1). What caused the basking sharks to school in this area is not known, however, observations of synchronised swimming activity by large numbers of sharks are consistent with courtship behaviour and mating (Wilson, 2004). If associated with courtship the observations would extend the basking shark breeding season from late spring through early autumn (Wilson, 2004).


Figure 1. Basking shark shoaling behaviour (copyright, Wilson 2004). The basking shark is also known to exhibit breaching behaviour, whereby the shark leaps out of the water, turns on its side and crashes back onto the surface. Its purpose is not fully understood, but may be a form of display during courtship behaviour either to attract females or to ward off competing males (Speedie, pers. comm.) Breaching is thought to be a means of social communication between predatory white sharks when entering seasonal reproductive mode (Pyle et al., 1996) and is used as a courtship display between filter-feeding whales (Whitehead, 1985) in competition for females. In a study conducted by Sims et al. (2000 b) only large basking sharks were observed breaching and only when three sharks interacted were multiple breaches observed in succession. During this study one breaching animal was identified as a female, suggesting this behaviour may serve as a signal of receptivity to the males. Breaching is thought to be most prevalent during May and June, the proposed mating season in UK waters (Matthews, 1950; Sims et al., 2000 a). 2.4 Population Status Presently no estimates exist for the global or regional population size of basking sharks. Compagno (1984) suggested that the global basking shark population was probably low, and this observation, together with knowledge of their life history characteristics, suggests the species is ‘extremely vulnerable to overfishing’. The global population status of basking sharks is assessed as ‘Vulnerable’ (A1a,d, A2d) in the 2000 IUCN Red List. Two subpopulations, the North Pacific and the North-East Atlantic are assessed as Endangered (EN A1ad). The IUCN assessment takes the following factors into account: basking shark biology and ecology; historical accounts of rapidly declining local populations during short term fisheries exploitation, followed by slow rates of recovery; the effect of fisheries bycatch, and future directed fisheries motivated principally by the


demand for fins from the oriental shark fin soup market. Mooney-Seus and Stone (1997) consider this species to be ‘data deficient’, and therefore it is unlikely that such assessments can be made with confidence. Mooney-Seus & Stone (1997) did however highlight the sharks’ potential vulnerability to targeted fisheries. Therefore the precautionary principle should be adopted when developing measures to manage and protect the basking sharks’ global, regional and local populations. 2.5 Distribution & Migration The basking shark is primarily coastal-pelagic, occurring in the temperate waters of continental and insular shelves of the Atlantic and Indo-Pacific Oceans and the Mediterranean Sea. The species is occasionally recorded offshore in oceanic waters but is most often encountered in close proximity to the coast. They are seasonally observed in both the northern and southern hemisphere in the following locations (FAO, 2004):

• Western Atlantic: Newfoundland to Florida; southern Brazil to Argentina. • Eastern Atlantic: Iceland; Norway and western Barents Sea to Mediterranean and Senegal; western Cape Province, South Australia, New Zealand. • Eastern Pacific: Gulf of Alaska to Gulf of California; Ecuador, Peru and Chile, Galapagos Islands (possibly).

Distribution is characterised by highly seasonal appearances indicating the migratory nature of the species (Sims et al., 2005). In high northern latitudes, including the UK, basking sharks are most commonly reported in surface waters between April and October, and are rarely seen during winter, as a result of their exploitation of surface-dwelling Calanus copepod concentrations generally in summer months (Phenix, 2007; Doyle et al., 2005; Sims et al. 2003 a; Southall et al., 2005). Their migration is both vertical (from deep to shallow water) and horizontal as sea temperature rises and plankton distribution changes. Due to the lack of data from southern European waters horizontal migrations have yet to be assessed from the Mediterranean. It was formerly accepted that in temperate latitudes the sharks migrate from deep-water wintering areas to shallow, coastal seas following seasonal increases in primary productivity. The presence of high levels of squalene in the shark’s liver oil in spring, subsequently replaced by Vitamin A later in the year, appears to confirm at least some measure of migration from deep to shallow water (Kunzlik, 1988). Some individuals move into shallower shelf waters, after a thermocline has developed (Sims & Quayle, 1998) and when prey is most abundant (Sims et al., 1997), supporting the concept of some degree of migratory behaviour in the species. Fifty years ago it was proposed that basking sharks migrate from coastal summer feeding areas of the northeast Atlantic to hibernate during winter in deep water on the bottom of continental shelf slopes, in order to maintain energy stores during seasons of apparently low productivity (Parker & Boeseman, 1954). There is no proof supporting the ‘hibernation’ theory and basking sharks have recently been shown to feed at much lower threshold densities of zooplankton than previously thought, suggesting that hibernation is not necessary (Sims, 1999). Tracking studies carried out by Save Our Seas Foundation, Defra, CEFAS and the Marine Biological Association have provided further evidence refuting the hibernation theory. Tracked basking sharks undertook extensive horizontal (<3,400km) and vertical (<750m) migrations utilising productive habitats on the continental shelf and shelf edge during summer, autumn and winter (Sims et al., 2003 a). Their long distance movements coupled with deep diving behaviour, used to locate discrete layers of prey (Josse et al.,


1998), suggest that these animals require both extensive horizontal and vertical movements in order to survive on patchily distributed zooplankton (Sims et al., 2003 a). Similar research tagging sharks off Massachusetts in NE USA has seen sharks migrate southwards to waters in Brazil and Haiti (Skomal, 2005). This research indicated that basking sharks remain in continental shelf edges during winter, spending a greater proportion of their time in deeper water than in near-surface waters (Sims et al., 2003 a). These studies failed to show interaction between the Northeast Atlantic and the Northwest Atlantic populations. However a more recent study tracked a single shark moving from the Isle of Man in 2007 to Canadian waters (Gore et al., 2008). Given the significant movement of these sharks, it is also unlikely that basking sharks form discrete local ‘UK’ populations as previously thought (Parker & Stott, 1965). Tracking has shown that sharks from the English Channel move to Scottish waters and vice versa over relatively short periods of time (2-3 months). However one tagged shark exhibited a degree of philopatry (loyalty to a discrete small area), returning to the English Channel after spending considerable time on the Bay of Biscay shelf edge (Sims et al., 2003 a). Basking sharks also appear to display pronounced seasonal and spatial population segregation. They are generally reported alone or in small groups, while shoals in excess of 100 individuals have also been recorded, albeit infrequently. Basking sharks caught in surface fisheries in Scottish waters were predominantly female (F:M ratio of 18:1, Watkins 1958), and 65-70% of sharks taken in fisheries in Japan were also female (Anon., 2002). In contrast, catches from sub-surface gill nets off Newfoundland were made up of twice as many males as females (Lien & Fawcett 1986). Pregnant females, juveniles and newborns are rarely recorded and little is known about their distribution (Anon., 2002). Basking sharks have been recorded all around the UK and Irish coast, although principally along the west coast of the UK and both the east and west coasts of Ireland. Generally the sharks are sighted close inshore, off islands and rock formations, off headlands, and in bays where their zooplankton prey may aggregate to feed on high concentrations of phytoplankton (Earll, 1990; Sims et al., 1997; Sims & Quayle, 1998). On a local scale (0.01-10km), basking shark distribution is determined largely by zooplankton abundance, particularly the presence of adult Calanus helgolandicus (Sims, 1999; Sims & Merret, 1997; Sims & Quayle, 1998; Hays, 2003), with sea surface temperature (SST) being less important at these small scales (Sims et al., 2003 a). However, at greater scales (10-100km) SST and in particular thermal boundaries characteristic of tidal and shelf break fronts correlate significantly with basking shark distribution and movement patterns in surface waters (Cotton et al., 2005; Phenix, 2007). The use of thermal fronts as foraging or migration corridors has also been supported by recent physiological (Brown, 2003) and behavioural studies (Sims & Quayle, 1998; Sims et al., 2003 a). It is also clear from anecdotal reports, and from research on the phenology of basking shark appearance at surface waters in spring of each year in UK waters, that the main environmental driver for sharks to appear in surface waters is when sea surface temperatures reach a threshold of 100 Celcuis (Phenix, 2007). These findings emerged from analysis, which combined MCS basking shark watch data in three hotspot regions with associated oceanographic, and plankton conditions. The fall in basking shark sightings from the UK hotspot regions coincided with a marked reduction or elimination of high copepod densities from surface waters.


2.6 Threats The basking shark’s surface feeding habit, large size and slow swimming speed make the species highly vulnerable to human-induced mortality from targeted fisheries, bycatch and disturbance. However, environmental pressures such as pollution and climate change may also pose additional threats to basking sharks through re-distribution of their prey. The shark’s slow intrinsic rate of population increase implies that stocks will take many decades to recover from depletion resulting from any of these factors. 2.6.1 Targeted Fisheries Basking sharks have been exploited by targeted fisheries off Scotland, Ireland, Norway, Faroe Islands, Iceland, California, China, Japan, Peru, Ecuador (Compagno, 1984) and Northern Spain (Anon., 2002). Historically, in the North Atlantic, the basking shark has been fished for several hundred years. Targeted fisheries have traditionally been driven largely by demand for high-grade oil contained within the sharks’ livers. The liver comprises about 17-25% of the total body weight (Phillips, 1947; McNally, 1976) and an average shark is thought to yield approximately 0.5 metric tonnes of oil (Anon., 2002). This oil has high squalene content (up to 55%). Squalene is unsaturated and therefore is a liquid, inert, colourless and odourless oil (Fairfax, 1998). Basking shark oil was originally used as lighting fuel for lamps during the 18th Century. However, many applications for squalene were developed: in the manufacture of cosmetics and pharmaceuticals, as a moisturiser, as a specialist precision lubricant, a surfactant, and as a constituent of dyes, artificial silk and perfume (Fairfax, 1998). Shark oils and cartilage in general are also in demand in capsule form as immune system boosters (Fairfax, 1998). Much of the oil landed in the UK in the 1980s and 90s was exported to Norway (Anon., 2002). Basking shark liver oil was replaced in the latter part of the 20th century by synthetics. Shark liver value declined from £550 per ton in the 1970s to approximately £250 per ton by the early 1990s (Fairfax, 1998). Over the later years of the 20th century, a 333% rise in shark fin value was reported due to an increased demand in the oriental shark fin soup market (Watts, 2001). The high value of basking shark fins in international trade facilitates the continued viability of the Northeast Atlantic fishery for this species (Anon., 2002). Following the establishment of 200 mile Exclusive Economic Zones around European Community countries in the 1970s, an annual quota for the Norwegian catch of basking sharks in EC waters was agreed in 1978 (Anon., 2002). The quota was 800 tonnes liver weight in 1982, and has since been gradually reduced (Anon., 2002). No part of this quota was taken for several years and in 2001 Total Allowable Catch was reduced to zero (EC Regulation 2848/2000) (Anon., 2002). It was reported that in 2000, 30 Norwegian vessels participated in the basking shark fishery and in 2001, only 13 vessels (Anon., 2002). In the 1970s, basking shark fins cost £3,000/tonne, (approx. US $5,800/t) but increased significantly to £20,000/t (approx. US $38,800) by 1994 (Fairfax, 1998) due to an increased demand for shark fin soup, which is considered a delicacy and status symbol in South East Asia. In 1996, a Norwegian fin processor reported that the price for dried basking shark fins was about £90/kg equivalent to £90,000 per tonne (Fleming & Papageorgiou, 1996). More recently, in 2000, 1m tall fins (presumed to be basking shark fins) fetched US $16,000 (approx. £8,000) in Beijing (Fowler, pers. comm.). Further reports from the U.S. support these reports, with a single basking shark fin selling for between US $10,000 and US $20,000 (£5,000 and 10,000) in the U.S (Shivji, pers.comm). It has been reported that basking shark fins imported from Norway are the most expensive fins in Singapore, where a bowl of shark fin soup costs £44 (Lum,1996). Every year 125 countries participate in fisheries and trade of over 30 to 100 million sharks of various species, producing over 8,000 tons of shark fins (FAO, 2004). World


trade for shark fin has risen by up to 400% in the last 15 years (Wildaid, 2004). However, what proportion of this trade consists of basking shark fins is currently unknown due to a lack of monitoring. The continued and unregulated expansion of the shark fin market may pose a very real threat to basking shark populations. The increase in demand for shark fins may increase legal and illegal landings of basking sharks on a global scale. The recent listing of the basking shark on the Convention on International Trade in Endangered Species (CITES) Appendix II requires the monitoring of trade in basking shark products and may facilitate responsible basking shark fishery management. The severity of the impacts of the shark-finning industry on shark populations has recently been recognised. In November 2004, the World Conservation Union (IUCN) adopted a recommendation urging all states to ban shark-finning and requiring fins to be landed attached to their bodies (which has been ratified and is being implemented in the UK). In addition, the International Commission for the Conservation of Atlantic Tunas adopted a US proposal in November 2004 to ban shark-finning in the Atlantic Ocean. Sixty-three countries have adopted the unprecedented protective measures. In Europe, Council Regulation (EC) 1185/2003 establishes a permit scheme for removal of shark fins by vessels which have the capacity to use all parts of the shark. This regulation pertains to all vessels in EC waters and EC vessels outside those waters. Basking sharks yield other products, such as meat for human consumption, hide for leather and the rendered carcass for fishmeal, however demand for these products is currently low. Chen et al. (1996) provided a landing value for whole basking sharks at fish markets in Taiwan as US $1.10/kg (in Phipps, 1996). Basking shark meat was sold in London in the 1970s, and in Scotland up until the early 1990s, when prices for the meat were between £0.30 and £0.80/kg (Fleming & Papageorgiou, 1996). It is impossible to determine the volume of cartilage entering international trade. Fleming and Papageorgiou (1996), however, report that cartilage capsules manufactured and sold in Belgian pharmacies and labelled ‘ex Ceatarinus maximus pulvis’ must have been imported as there is no basking shark fishery in the southern North Sea. Belgium also exports this product to France, Portugal, Germany and Switzerland (Anon., 2002). The paucity of data regarding basking shark ecology severely limits the accuracy of population trend analysis for the species. However, a small number of reasonably well-documented fisheries records are useful for providing data on stock declines and population recovery. Fifty to 90% reductions in basking shark catches have been documented in some fisheries over short periods of time, and these declines appear to have led to long-term loss or reduction in some local populations (Fowler, pers. comm.). Rather than one factor being solely responsible, it is likely that fishery closure in these cases resulted from the combined effects of dwindling shark numbers, diminishing product markets, reduction in government subsidies and more recently implementation of international and national conservation measures and protective legislation (Parker & Stott, 1965; Kunzlik, 1988; Pauly, 2002, Sims & Reid, 2002). The Achill fishery off Western Ireland was established in 1946 and recorded a catch of over 1,000 sharks annually between 1951 and 1955 (McNally, 1976). The collapse of this fishery was attributed to overexploitation of local stocks (Parker & Stott, 1965) - too many sharks were caught before they had the opportunity to breed, otherwise known as ‘recruitment over-fishing’. During the 1950s, the Department of Fisheries and Oceans of Canada conducted a basking shark eradication scheme in the West Coast of Vancouver Island following complaints from salmon fishermen whose nets were being damaged by basking sharks. Over 100 basking sharks were killed between 1955 and1956 and in 1994 the local shark population had not recovered to original levels (Darling & Keogh, 1994).


The most recent estimate of population productivity (rMSY range from 0.013 to 0.023), has been based on a range of low confidence assumptions (CITES, 2002). This is a particularly low level of productivity and is lower than previous estimates of 0.16 (www.FishBase.org). Minimum population doubling time has been estimated as 14 years (Musick et al., 2000). Therefore it is clear that high mortality rates (for example due to fishing pressure) can have severe impacts on basking shark populations. Reducing the population to extremely low numbers may prevent the population from recovering to its original level, as has occurred off Vancouver Island. As identified in the first UK proposal to list the basking shark under Appendix II of CITES, past fisheries records indicate that documented annual catches from targeted fisheries have only ever been in the order of hundreds to low thousands (DETR, 1999). Between 1952 and 2004 81,639 basking sharks, which were recorded, were removed from the Northeast Atlantic (ICES, Anon., 2002). Global landings and Northeast Atlantic landings have fluctuated but have continuously declined over the past few decades. Variations in catches in this area may be related to broad-scale changes in the ocean influenced by factors such as summer stratification, the North Atlantic Oscillation (NAO) or climate (Sims & Reid, 2002), resulting in altered basking shark distribution and subsequent lower fishing effort. Understanding the impacts of exploitation is further confounded by the poorly understood, and thus unpredictable nature, of temporal and spatial distribution of basking sharks, which appear to be driven by oceanographic processes (Sims & Quayle, 1998). In addition the current lack of understanding of basking shark migration, as well as stock size and structure, makes it difficult to relate fluctuations in local abundance to specific factors such as exploitation. In the absence of a clear appreciation of basking shark ecology, fisheries mortality modelling suggests that this species is unable to withstand targeted exploitation for extended periods and strongly indicates that stock depletion is likely to be a major factor affecting fishery yields (Pauly, 2002). 2.6.2 Incidental Bycatch Incidental take or by-catch, associated with other fisheries, is mainly reported in set nets and trawls and is most common in coastal waters. Berrow (1994) calculated that between 77 and 120 sharks were taken annually in the bottom set gill net fishery in the Celtic Sea (south of Ireland). Twenty-eight records from fishermen of sharks entangled in fishing gear (mostly surface gill nets) were received in 1993 (Berrow & Heardman 1984), representing almost 20% of all records for that year. At least 22% of these sharks died as a result of the entanglement. There is evidence from Newfoundland (Lien & Fawcett 1986) that some incidental fisheries may become targeted fisheries as markets for the products develop. Basking sharks caught as bycatch in Norway could yield 70-90 kg of fins, which is equivalent to £1,500 (US $2,000) per shark (www.fis.com/fis/ hotnews in Anon., 2002). Although it is possible in some cases to successfully disentangle live basking sharks, the high value of their fins and other commodities may be incentive enough for fishermen to kill and utilise the shark rather than to release it. It is important to note that the authors have found no evidence to suggest that this occurs in UK territorial waters. Lien & Fawcett (1986) recorded that over 410 basking sharks were caught between 1980 and 1983 in salmon gill nets and cod traps off Newfoundland. In the Isle of Man, 10-15 basking sharks have been by-caught in the herring fishery annually and further bycatch as a result of entanglement in pot fishermens’ ropes has also occurred (Watterson in Anon., 2002). Entanglements in nets and ropes have also been reported from Scotland and Southwest England during MCS Basking Shark Watch. Observer data from oceanic gill net fleets suggests that only about 50 basking sharks were taken annually in offshore areas in the Pacific Ocean (Bonfil, 1994).


http://www.fis.com/fis/

2.6.3 Disturbance Sources of disturbance include boat traffic, aircraft noise, fishing activity, naval sonar, offshore developments, seismic testing and surveying, aggregate extraction and/or oil drilling and exploration (Kelly et al., 2004). Long-term effects of repeated disturbance or harassment could include loss of weight or condition or reduced reproductive success (Kelly et al., 2004). Basking sharks are vulnerable to collisions with boats due to their tendency to feed close to the surface in bays and coastal locations in the summer when surface vessels activity is also high. In 2004 MCS received one report of a dead basking shark in Holyhead Harbour, which had been hit by a ferry, and two reports from sailors who accidentally hit basking sharks and reported that the sharks appeared to have suffered injuries. Disturbance by boats has been reported to MCS on numerous occasions and basking sharks have reacted by diving deep and moving away from the area. Since 1987, reports of harassment by divers, surfers and rowers have also been reported to MCS and were usually associated with apparent distressed behaviour by the basking shark. However, the extent to which collisions occur and the impact this has on the population is difficult to establish, as the majority of incidents presumably remain unreported. 2.6.4 Environmental Pressures A range of environmental factors including chemical pollution, marine debris, habitat loss or degradation and climate change can affect basking sharks. Heavy metals such as cadmium, mercury and lead are highly toxic in animal tissues, even at low concentrations. Cadmium and lead have been found in tissue samples of six shark species in the eastern Mediterranean (Watts, 2001). Heavy metals can inhibit DNA synthesis, alter heart function, disrupt sperm production and alter blood composition (Watts, 2001). Furthermore the organic pollutant Tributylin (TBT) has been detected in the kidneys of blue sharks off the Italian coast (Corsolini et al., 1995 in Watts, 2001). Not only can chemical pollution directly affect sharks by damaging basic biological functions, but it can suppress photosynthesis in phytoplankton resulting in a loss of primary production, and can cause changes in species composition and diversity of zooplankton assemblages (Watts, 2001). An estimated 6.5 million tonnes of plastic are discarded every year by ships (Watts, 2001). Plastic debris at sea results in damage to marine fishes and mammals (Dufault & Whitehead, 1994; Laist, 1997). Entanglement / encircling by plastic debris has been recorded for several shark species (Laist, 1997). Sharks exhibit highly investigative behaviour towards inanimate objects in their habitat, which may lead to such occurrences (Bird, 1978). Plastic entanglement can lead to severing of fins, and ingestion of plastic can result in the destruction of the shark’s gills and asphyxiation (Simpfendorfer, 2000). Predicted climate change scenarios are anticipated to displace and alter marine ecosystems significantly. Recent evidence suggests that copepod abundance in the North Atlantic, North Sea and North Pacific is decreasing, and copepod species composition is changing in response to increasing trends in Northern Hemisphere temperature and the North Atlantic Oscillation (Beaugrand et al., 2002; Edwards et al., 2004). The decline in abundance of important planktonic prey, and shifts in their seasonality, has recently been implicated in exacerbating the decline in North Sea cod stocks (Beaugrand, et al., 2003). Changes in the abundance, species composition and seasonality of copepod zooplankton could have effects on the seasonality, distribution and numbers of basking sharks, as their distribution and behaviour appear to be closely linked to that of their food source. There is currently a move towards the use of renewable energy sources throughout the world, and for Britain, having the highest wind resource in Europe, offshore wind power represents a valuable resource (BWEA, 2005). The introduction of the UK Government’s


Utilities Bill, which places an obligation on electricity suppliers to provide an increasing amount of power from renewable resources, will increase development of offshore renewable energy developments such as windfarms, marine current turbines, and tidal power generators. The majority of suitable locations for these generators are located along the Irish Sea coast (Gill &Taylor, 2001), where, according to MCS data, basking shark surface sightings are most common. These developments could affect basking sharks and other elasmobranch species during the construction phase, operation and de-commissioning. During construction and de-commissioning, elasmobranchs in general may be disturbed due to the disruption of food supplies (Gill & Taylor, 2001). Construction may also result in permanent changes in current patterns which may be significant for basking sharks as changes in the current pattern may affect the location and abundance of fronts, where basking sharks tend to concentrate their feeding effort (Gill & Taylor, 2001). In addition, noise and vibrations during operation of installations could act as deterrents to elasmobranchs (Gill & Taylor, 2001). The installation of offshore energy developments will require the transport of electricity via submarine cabling, which produces electromagnetic fields (Gill & Taylor, 2001). Sharks exploit the electric outputs of organisms in saltwater, to detect and capture prey (Bullock, 1973; Kalmijn,1982). It is therefore possible that these species may detect and respond to the electromagnetic fields produced by offshore power installations and underwater cables. Evidence for use of electroreception for prey detection or navigations is lacking for the basking shark, however they do possess electroreceptors and therefore could potentially be affected by the electro-magnetic fields generated by underwater cables. There is a dearth of definitive published information relating to whether electric fields produced by underwater cables have any effect on electrosensitive species (Gill & Taylor, 2001). Preliminary research has shown that the benthic shark, Scyliorhinus canicula, avoids electric fields at 1,000 µV/m which are the maximum predicted to be emitted from 3-core undersea 150kV, 600A cables connecting offshore wind turbines to the mainland (Gill & Taylor, 2001). As the basking shark is pelagic rather than benthic, the effects of electromagnetic fields on the species may be minimal. Further long-term research on the avoidance behaviour by elasmobranchs is required, in addition to short term species-specific studies to determine the response of species to electric fields, the extent of individual variability in their response, the effect of temperature on the response, and the various species’ habitat-use. It is also imperative to determine habitat-use by elasmobranch species over time, whether certain species are attracted to specific locations at any point in their lifecycle or at specific times of year. This information will be crucial for deciding on site location and the timing and decommissioning stages of the development. The Basking Shark Watch project provides information on the hotspot locations of surface basking shark sightings, and to some extent the seasonal and annual variations in distribution of surface sightings. This dataset will be increasingly important for identifying areas and times when basking shark surface sightings are abundant, in relation to proposed renewable and other offshore developments. 2.7 Current Protection and Management Since the collapse of many basking shark fisheries, and the recognition that the basking shark is particularly vulnerable to targeted fisheries, the species has gained increased protection both nationally and internationally. Most significantly, it received international protection through listing on CITES Appendix II in 2003, and listing on the Bonn Convention on Migratory Species (CMS) in 2005, and Common Fisheries Policy protection in 2007. The lack of population statistics, and highly migratory nature of the species, has resulted in a debate over the relevance of local site protection measures even though research identifying critical habitat for basking sharks has been extensive in UK waters since 2000. UK government is currently developing legislation with the UK marine bill (summer 2008). The Finding Sanctuary project (www.finding-sanctuary.org)


http://www.finding-sanctuary.org/

in England is tasked with gathering data on the distribution of migratory species such as cetaceans and basking sharks for implementation into a new MPA network that should be ratified by UK government by 2012. As such, there may be key areas recommended from this work which consistently attract basking sharks that will lead to spatial protection measures being implemented for the species. 2.7.1 National Basking shark protection at national levels has been divided into countries of the Northern hemisphere, and then countries of the Southern hemisphere. Northern Hemisphere United Kingdom: In March 1998 the basking shark was afforded full protection within British territorial waters under Schedule 5 of the Wildlife and Countryside Act (WCA) 1981. This listing protects the shark from intentional killing, capture, or disturbance out to 12 nautical miles (nm) around the coast of Great Britain. Under the Act, it is also illegal to sell, offer to sell, or possess any part of a basking shark within Great Britain. This protection followed a ten-year campaign by MCS in collaboration with other organisations and agencies, and data from MCS Basking Shark Watch was influential in the success of this campaign. The species is protected from ‘intentional and reckless’ disturbance out to 12nm in England and Wales through the Countryside and Rights of Way Act (2000) and in Scotland under the Nature Conservation (Scotland) Act (2004). Furthermore the Nature Conservation Act required the development of a Scottish Marine Wildlife Watching Code to guide basking shark and cetacean watching operations. Protection of the basking shark in Northern Ireland waters is under consideration as part of the review of ‘The Wildlife (Northern Ireland) Order 1985’ (Environment and Heritage Service, pers. comm.). Furthermore, the UK Biodiversity Group lists the basking shark as a priority species subject to a Species Action Plan (SAP). The SAP outlines measures for the protection of the shark in UK and international waters with a view to maintaining the current basking shark population (UK Biodiversity Group 1999). UK Crown Dependencies: The species also receives protection in the following UK dependencies: Isle of Man: The basking shark is protected under Schedule 5 of the Manx Wildlife Act (1990) in Manx territorial waters (to 12 nautical miles). Under Section 9 of the Wildlife Act it is an offence to kill, injure or catch basking sharks. It is also an offence for someone to have in their possession a basking shark or any part of a basking shark or product derived from a basking shark. Selling or transporting basking sharks or their parts or products is also an offence. The Act also states that it is an offence to disturb basking sharks and to damage or obstruct access to an area used by basking sharks for shelter or protection. Jersey: Conservation of Wildlife (Jersey Law) (2000) protects basking sharks from killing and capture out to 12nm. Guernsey, Alderney and Sark: Under the Fishing Ordnance (1997) Part I, Section II it is an offence to take, kill, injure, land, import, export, buy, sell or possess a basking shark. If a basking shark is accidentally caught it must be returned to the sea. The protective measures extend out to 3nm territorial limit. Ireland: At present the basking shark remains unprotected in Irish waters. Malta: The basking shark was protected under Schedule II of the Flora and Fauna (Protection) (Amendment) Regulations (1999).


Sweden: Basking sharks are protected under the national fishing regulations, set by the National Board of Fisheries. 15 (http://195.17.253.245/index2.htm) USA: In Florida State, at the very southern edge of their range, basking sharks receive full protection out to 9nm on the Gulf coast, and out to 3nm on the Atlantic coast. In federal Atlantic and Gulf waters (3-200nm), the landing or sale of basking sharks by direct commercial or recreational fisheries is prohibited under the US Fishery Management Plan. This prohibition was enacted in order to prevent targeted fisheries from developing, recognising the vulnerability of the sharks to overexploitation. While the Shark Finning Prohibition Act (HR 5461), does not ban the sale of shark fins, it prohibits their landing or possession in all US federal waters without the entire shark carcass, effectively stopping the easy handling of large quantities of shark fins as bycatch. Southern Hemisphere Australia: The basking shark is currently not listed by the Australian Society for Fish Biology (ASFB) as a threatened fish species and is not protected. The basking shark has rarely been encountered in Australian waters and more data are necessary to accurately determine the status of the species in this area, although they may occur in the Great Australian Bight marine park (Pogonoski et al., 2002). Basking sharks have been protected in Tasmanian waters under the Fisheries Regulations (1996) since 1998. New Zealand: In New Zealand, the Fisheries Act (1983) provides partial protection for basking sharks as well as several other fish species (including some teleosts). Commercial targeting of basking sharks has been banned since 1991, although the sharks may be taken as bycatch. The liver and fins may thus be landed if arising from bycatch and sold to any market, national or international. The basking shark bycatch fishery is not managed by the New Zealand Quota Management System (QMS) (Duffy, 2002). Basking sharks have been recorded in a Marine Mammal Sanctuary in New Zealand where they are protected from gill netting during their period of peak abundance (Duffy, 2002). 2.7.2 International Convention on International Trade in Endangered Species (CITES) Bonn Convention on Migratory Species (also known as CMS 18 www.europa.eu.int 16 www.cms.int) This Convention aims to conserve migratory species throughout their range and lists migratory species that would significantly benefit from international cooperation. Basking sharks meet the criteria for addition to Appendix II as they are a migratory species. Research conducted by the CEBS, CEFAS and MBA carried out between 2001 and 2005 led to confirmation that basking sharks undertake significant migrations between NE Atlantic states (Sims et al., 2005) (Fig. 2). The UK basking shark Biodiversity Action Plan working group met in December 2004 in order to discuss the trans-boundary migratory behaviour of the shark, and the implications for conservation of the species. It was agreed at that meeting in accordance with representatives present from Defra and JNCC that the species merited addition to the Convention on Migratory Species. MCS subsequently prepared the formal CMS proposal for the basking shark which included recent research information from satellite telemetry results from the Northeast Atlantic, and similar information from the Northwest


http://195.17.253.245/index2.htm

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Atlantic where a basking shark moved from Northeast USA to the Caribbean in late 2004 -early 2005 (Skomal et al., 2005) (Fig 2).

Figure 2. Basking shark tracking work carried out by the Marine Biological Association

(left), and the Massachusetts Dept of Fisheries (right). The basking shark was officially listed on Annex I and II of the CMS at the Convention of The Parties meeting in Nairobi in November 2005, after the scientific committee of the Convention reviewed the data within the Marine Conservation Society proposal. The requirements of nation states that sign the Convention are to:

1. Introduce necessary conservation legislation for the species. 2. Introduce management mechanisms. 3. Write Memoranda of Understanding between adjacent states which share a

contiguous population (e.g. France, Ireland and the UK). 4. Ban landings and trade.

Significant parties that held a ‘reservation’ (i.e. could not support the listing) were:

• Portugal (not well briefed on the species by their own nature conservation advisors);

• Norway (not part of EC, and up until 2000 set their own quota to catch basking sharks, and may wish to fish them in the future);

• Denmark (on behalf of the Faroes who take basking sharks in artisanal fisheries); and,

• The EU (who had no legislative mechanisms by which they could protect the basking shark at the time of listing). The shark is not on the Habitats Directive Annex 1, and the shark was not protected within the Common Fisheries Policy (CFP) regulations at the time of the CoP.

The EU argued that they could not protect the basking shark, given the lack of necessary legislation to protect the species that is currently in place in EU waters, particularly outside territorial seas of some member states which have their own inshore protection legislation (e.g. UK seas under the Wildlife and Countryside Act, 1981 – listed in 1998). This obstruction to protection in offshore EU (12-200nm) waters was remedied in 2007, when the basking shark was listed under CFP regulations that banned the trade, sale or trans-shipment of basking shark parts in EU waters, or in any international waters by EU-registered vessels. Previously sharks were landed as ‘bycatch’ from ICES blocks VIIIa-e (the Bay of Biscay region), and could be sold in countries where no domestic legislation previously existed to protect the species (e.g. France – see Fig 3).


This is now not possible, as it is illegal to trans-ship any basking shark part in all European waters.

Figure 3. Basking shark on sale in Bordeaux hypermarket caught in the Bay of Biscay, February 2005. (Source unknown)

CITES The CITES Convention was established in response to concerns about the potential detrimental effects on species’ survival of high levels of international trade in wild animals and plants. It establishes the international framework for the prohibition of commercial trade in endangered species (listed in Appendix I), and for the regulation and monitoring of trade in certain other species listed in Appendix II and III (Fowler, 2002). The first application for listing the basking shark on CITES Appendix II was made in April 2000, but was narrowly defeated. The proposal was revised and resubmitted to the Twelfth Conference of the Parties to CITES (CoP XII) in November 2002 (Anon., 2002). At CoP XII the UK successfully persuaded a sufficient number of member countries to support the proposal and the basking shark was listed on CITES Appendix II. Article II of CITES states that ‘Appendix II shall include all species which, although not necessarily now threatened with extinction, may become so unless trade in specimens of such species is subject to regulation in order to avoid utilisation incompatible with their survival’. A number of reasons were given in the UK proposal for listing the basking shark on Appendix II (Anon., 2002):

• Considered Vulnerable in 2000 IUCN Red List (IUCN 2000). • Biology makes it especially susceptible to exploitation. • Catches in well-documented fisheries have declined by 50-90% over short time periods.These declines have persisted with no apparent recovery following cessation of exploitation. • Demand for basking shark fins has increased. A single fin can fetch US$ 100-300kg dried and a single shark can yield 90kg of fins. • Meets the criteria listed in the Conference Resolution Conf. 9.24, Annex 2a, namely that ‘it is known, inferred and projected that harvesting of specimens from the wild for international trade has, or may have, a detrimental impact on the species by exceeding, over an extended period, the level that can be continued in perpetuity’.


A CITES Appendix II listing does not ban trade, but establishes that a permit is required to export a listed species or products from that species. These permits will only be granted if the Scientific Authority of the CITES exporting party concerned has advised that such trade will not be detrimental to the survival of the species. Successful implementation of an Appendix II listing requires the identification of basking shark products in international trade. The UK has produced and circulated an identification guide to basking sharks and their fins, their most valuable product. Monitoring the numbers of imported and exported fin sets would therefore enable the numbers of individual sharks entering trade to be assessed. Less valuable products such as liver oil, cartilage and meat are more difficult to identify, however DNA tests have been developed to test for basking shark products (Anon., 2002). This listing should help ensure that exploitation of this globally threatened species is regulated and monitored and that international trade is not detrimental to the survival of the species. Although not proposed for inclusion in Appendix I, the UK maintains that the species meets criteria C for inclusion in Appendix I as ‘a decline has been either observed as ongoing or as having occurred in the past, and is inferred and projected on the basis of levels or patterns of exploitation’ (Anon. 2002). The Appendix I listing is reserved for species threatened with extinction and prohibits all commercial trade in the species and its products, except under exceptional circumstances. Only a few marine fish species have been listed in any of the CITES Appendices. Other elasmobranches which have received protection through Appendix II listing include the whaleshark (Rhincodon typus), and more recently the great white shark (Carcharodon carcharias) in October 2004. The Appendix II listing should, in theory, provide the basis for assessing the extent of legal international trade in basking shark products. Once this has been established, the need for an Appendix I listing for the conservation of the basking shark should be re-considered. FAO International Plan of Action for the Conservation and Management of Sharks (IPOA-Sharks) adopted by the UN Food and Agriculture Organization (FAO) in 1999. Management and monitoring of the basking shark, and other species of sharks taken as bycatch and in directed fisheries, are required under the IPOA Sharks. The IPOA aims to ensure conservation and management of sharks and their long term sustainable use, requiring States that voluntarily adopt the plan to identify and pay special attention, in particular, to vulnerable or threatened species, and facilitate the identification and reporting of species-specific biological and trade data (Anon., 2002). Due to the voluntary nature of IPOA, CITES presently offers the only established, effective means of monitoring international trade data at species level. Mediterranean The basking shark is listed on Annex II to the ‘Protocol Concerning Specially Protected Areas and Biological Diversity in the Mediterranean’ of the Barcelona Convention (1976) which, although signed by Contracting Parties (Greece, Spain, France, Italy and 21 non-member States bordering the Mediterranean) on 10 June 1995, awaits full ratification. It introduces national or local measures that the Parties must take in order to protect threatened or endangered species such as the basking shark. The basking shark will only receive full protection in the Mediterranean once the Convention is ratified and appropriate legislation is in place (such as the legislation in Malta). The Mediterranean population was also added to Appendix II (strictly protected species) of the Bern Convention on Conservation of European Wildlife and Natural Habitats in December 1997. The aims of this convention are to conserve wild flora and fauna and their natural habitats, especially those species and habitats whose conservation requires the co-operation of several States, and to promote such co-operation. Particular emphasis is given to endangered and vulnerable species, including migratory species (ICES, 2003).


2.7.3 Additional Protection Measures As basking sharks are migratory, legislative protection in individual areas or regions may still leave migrating populations vulnerable to unregulated and unsustainable fisheries in other areas. This is relevant where migratory populations straddle national boundaries, or protection measures only extend a short distance from respective coastlines. Therefore, further protection under multi-lateral environmental agreements is necessary. These may be forthcoming as a result of the listing on the Bonn Convention on Migratory species in 2005. The basking shark is not currently listed under the European Habitats Directive (1992) (92/43/ EEC). The Habitats Directive aims to contribute towards protecting biodiversity through the conservation of natural habitats and wild plants and animals. The Habitats Directive requires the establishment of a European network of sites that will make a significant contribution to conserving the habitat types and species identified in Annexes I (habitats) and II (species). The listed habitat types and species are considered to be most in need of conservation at a European level. Each Member State is required to prepare and propose to the European Commission (EC) a national list of sites for each of the features which occur in their European territory, which will be evaluated in order to form a European network of sites of community importance (SCIs). These will eventually be designated by the Member States as special areas of conservation (SACs). These SACs, together with Special Protection Areas (SPAs) classified under the Birds Directive (79/409/EEC), collectively form the Natura 2000 network. The Commission formally adopted this list on 7 December 2004, meaning that these areas are now fully protected under the Habitats Directive. Annex II (as amended by the 2003 Treaty of Accession) currently lists 788 species, of which 58 have been recorded in the UK (excluding Gibraltar) since 1900, but only 9 marine species that occur in the UK are included on this list. Including the basking shark on Appendix II of the Habitats Directive would allow the designation of Special Areas of Conservation for basking shark protection, not only in the UK but in all Member States where the basking shark occurs. MCS data has identified hotspot regions around the UK, where basking sharks appear to occur in large numbers every year. Designating sites within these hotspots for their protection could help reduce threats in these areas, such as collisions, harassment and bycatch. SAC designation for basking sharks would require Member States to establish conservation measures that correspond to the ecological requirements of basking sharks present on the site, and to take appropriate steps to avoid deterioration of the natural habitats of basking sharks, as well as significant disturbance of the species. This includes the appropriate assessment of the implications of any plans or projects that, alone or in combination, are likely to have a significant effect on the site in view of the site’s conservation objectives (www.jncc.gov.uk). This would become increasingly important if the escalating number of offshore renewable developments were found to affect basking shark behaviour or habitat use. The Marine Conservation Society Basking Shark Watch Project could provide vital data for identifying key hotspot areas for basking shark protection. The basking shark is listed under Annex I of the United Nations Convention of the Law of the Sea (UNCLOS) 1982, as a ‘highly migratory species’. UNCLOS came into force in 1994 and provides a framework for the conservation and management of fisheries and other uses of the seas (Fowler, 2002). Its provisions on the Exclusive Economic Zones (EEZ) of coastal states and high seas require cooperation between states for the conservation and utilisation of highly migratory species.


2.8 Basking Shark Research & Sightings Projects In addition to MCS Basking Shark Watch, other sightings schemes and research projects are also contributing to our understanding of basking shark behaviour and distribution in UK waters and beyond. 2.8.1 Conserving Endangered Basking Sharks Project (2003 - 2006) This project was established in 2003 and brought together six organisations (The Marine Biological Association, Marine Environmental Research/UK Wildlife Trusts, Hebridean Whale and Dolphin Trust, International Fund for Animal Welfare, Marine Conservation Society, and The Shark Trust) that have collected survey and behavioural data on basking sharks. The aims of the project were to centralise these data to quantify the distribution and population size of the basking shark in UK waters, and to identify its critical habitat and movements in relation to the current protection zone at the time of the project (which was only in inshore territorial waters for Great Britain). The specific objectives were to:

• Map the distribution and movements of basking sharks from data collected by project partners within a single, spatially explicit database (ArcGIS). • Identify the environmental characteristics of their preferred habitat by analyzing shark locations with respect to these variables (e.g. water depth, sea surface temperature, prey abundance trends). • Quantify the annual number of sharks in UK waters by analysing survey data with bias reduction techniques based on sighting probabilities calculated using both survey and behaviour datasets; and • Assess, using spatial modelling, whether expansions of the protection zone (up to 200 miles) will encompass the major part of basking shark habitat off UK coasts.

The work helped to identify critical habitat, but determination of population size was not possible. It provided robust scientific information that was used to influence policy and management of the shark at the UK and international level. The results formed the basis for the proposals to list the basking sharks on Appendix I and II of Convention on Migratory Species (Bonn Convention) in 2005. The MCS Basking Shark Watch data was utilised by the CEBS project team in conjunction with the MBA-derived data from tracking sharks, and has shown consistency in highlighting the same key surface hotspots for shark activity in UK waters (Southall et al., 2005) http://www.mba.ac.uk/Fellows/Sims/cebs.htm http://www.mcsuk.org/baskingsharks/info.htm 2.8.2 Defra, CEFAS & the MBA A three-year project (2001-2004) aimed at providing much needed scientific information about the movements, distribution and population dynamics of basking sharks in European waters was launched in February 2001 by the Centre for Environment, Fisheries and Aquaculture Science (CEFAS), a branch of the Department for the Environment, Food and Rural Affairs (Defra). The study, which is jointly funded by The Global Wildlife Division of Defra, CEFAS and the Marine Biological Association of the UK (MBA), involves the use of “pop-up” archival satellite tags to reveal the behaviour and geographical movements of basking sharks. In March 2004, a further two-year study commenced involving the use of state-of-the-art molecular genetic analysis methods, but didn’t accumulate enough genetic material samples to come to any firm conclusions. http://www.defra.gov.uk/ ttp://www.cefas.co.uk/sharks/default.htm http://www.mba.ac.uk/


http://www.mcsuk.org/baskingsharks/info.htm

http://www.defra.gov.uk/

http://www.mba.ac.uk/

2.8.3 European Basking Shark Photo Identification Project (EBSPIP) The European Basking Shark Photo-identification Project is a database of basking shark images designed to aid the identification of individual sharks. The identification of individual animals from distinct body markings due to pigmentation, abnormal growth or injury, by using photographs (photo-identification) is a proven method of study for a variety of terrestrial and marine species. In the marine environment, photo-identification has transformed the study of many whale species and is thought to have potential as a viable technique for basking sharks. Photographs contained in the EBSPIP database are currently being analysed to identify matches. www.baskingsharks.co.uk 2.8.4 The Wildlife Trust Basking Shark Project The Wildlife Trusts Basking Shark Project was established in 1999, and in 2006 completed eight years of effort-corrected line transect surveys in the waters off the west coast of the UK. During the first three years (1999-2001), the project concentrated on the south coast of Devon and Cornwall, whilst in the period 2002-2004 the project covered the waters of the Irish Sea, Northern Ireland, Firth of Clyde and the Inner Hebrides, in addition to the south coasts of Devon and Cornwall. Local volunteers were also trained in survey techniques to help carry out future research independent of the project. During the entire period, the survey covered a total distance of 12,820 km, and 1,323 hours of timed observation, recording 399 shark sightings in total. Several key sites for the species were identified, including the area around Lizard Point and Lands End in Cornwall, the Lamont Shelf in the Firth of Clyde, and the area between Canna and the Hyskeir light in the Inner Hebrides. Most of the sharks sighted have been photo-identified, and the project has also generated a significant amount of film footage of various basking shark behaviours. The Wildlife Trusts will initiate a new three-year research programme in 2005, continuing the localised study of the western English Channel, before moving North in early July to spend more time in the waters of western Scotland. This project builds on the Seaquest South-West Project, a volunteer marine sightings scheme administered by Devon and Cornwall Wildlife Trusts since 1998. The scheme collates regional volunteer information on the marine life found around the coasts of the two counties. http://baskingsharks.wildlifetrusts.org/ 2.8.5 Save Our Sea Foundation Basking Shark research One of the principal locations where basking sharks have been regularly seen is in Southwest Scotland, where sharks are sighted mainly between mid and late summer. Researchers (Rupert Ormond and Mauvis Gore) are undertaking a project funded by The Save Our Seas Foundation, which aims to determine whether:

• Basking sharks feed year round at depth as well as on the surface, • The basking shark population is smaller or larger than previously assumed; and, • There is a relationship between the occurrence of sharks, zooplankton abundance and other habitat features.

The project aims to develop a conservation tool for basking shark population monitoring. In addition, a mobile educational exhibit will be created to raise public awareness of basking sharks and to promote the aims of the study. This research tracked basking sharks between the waters of the Isle of Man and Canada (Gore et al., 1998). 2.8.6 Isle of Man Basking Shark Watch Project The Isle of Man Basking Shark Project was established in the early 1980s and is the research arm of the Island’s conservation charity; The Basking Shark Society. The objective of the project is to achieve, “through scientific research and public education, an understanding of the natural history of what remains one of the most mysterious species in the world” (Basking Shark Society 1998). This has now been succeeded by a Manx Wildlife Trust Basking Shark project (www.manxbaskingsharkwatch.com) that


http://www.baskingsharks.co.uk/

http://baskingsharks.wildlifetrusts.org/

http://www.manxbaskingsharkwatch.com/

collaborates with the Marine Conservation Society Basking Shark Watch UK-wide project, and the Save Our Seas Foundation project (above). Full collaboration and data exchange of sightings information has been ongoing since 2005. 2.8.7 Irish Whale and Dolphin Group http://www.iwdg.ie In 1992 Simon Berrow, founder of the Irish Whale and Dolphin Group (IWDG), developed a basking shark public sightings scheme in Ireland, not dissimilar to the Basking Shark Watch Project. Since then, IWDG continues to receive basking shark data and maintain a database of records, although they do not currently actively solicit basking shark records. 2.8.8 Seawatch Southwest In 2007 a project was developed to record marine and avian megafauna sightings off Gwennap Head in Cornwall (southwest Lands End). A large number of basking sharks were observed interacting at the surface. The project intends to run for at least 5 years. A full report is available for download – www.seawatch-sw.org 2.8.9 APECS L’Association pour l’Etude et la Conservation des Selaciens (APECS) is a French-based shark and ray conservation group based in Brittany. Their studies encompass mapping the distribution of sightings gathered from the general public, from their own vessel-based effort surveys and from PAT satellite telemetry of tagged individual sharks. The organization lobbies French government and fisheries officials for better protection for the species, and for management, which leads to recovery of denuded populations. APECS data has in the past been incorporated into the MCS Basking Shark Watch dataset, and was presented at the European Marine Conservation meeting in Stralsund in May 2006 (Solandt et al., 2006), and at the European Elasmobranch Association conference in Brittany, November 2007. 2.8.10 Phenology of basking shark movement patterns In 2007 MCS collaborated with The University of Edinburgh; SAHFOS1 and the NOC2 to investigate the phenology of basking shark surface sightings in UK water hotspots (Southwest England; Isle of Man and West Scotland) in relation to Sea Surface Temperature and copepod density distributions (Phenix, 2007). The research identified SST as being the major driver for basking sharks to appear at surface waters at the hotspot regions, and reduced copepod densities to be the most significant variable to lead to the significant reduction in numbers of basking shark surface sightings on an annual basis (see Discussion at the end of this report).

1 SAHFOS – Sir Alistair Hardy Foundation on Ocean Science based at the Marine Biological Association, Plymouth. 2 NOC - National Oceanohraphic Centre, Southampton


http://www.iwdg.ie/

http://www.seawatch-sw.org/

3. Methods 3.1 Project Background

Basking Shark Watch originally aimed to provide a general indication of the geographic distribution of shark surface sightings around the UK coast (Earll & Turner, 1992). However, the duration of the project and the project methodology has been adapted accordingly.

In brief, the scheme engages members of the public and other organisations in recording and reporting details of basking shark sightings. The scheme has been promoted via: direct mail, national press, radio, television, various magazine advertisements and articles, and educational posters sent to key coastal locations and relevant organisations. The information is subsequently collated by the Marine Conservation Society (MCS) and entered onto the project database.

Records are now collected online (www.mcsuk.org), by telephone, or via pre-printed report cards that are distributed through key locations or sent direct on request to members of the public. 3.2 Promotion Basking Shark Watch promotional effort has varied during the project and is described in detail in Appendix A. The project was promoted to a wide audience via television and radio following the launch of the new poster and report cards in April 2001. In 2004 and 2006 adverts and articles were placed in appropriate magazines and newspapers (e.g. Dive magazine, RYA magazine) throughout the year. The MCS basking shark webpages - www.mcsuk.org are updated each month during the basking shark season and include maps of basking shark sightings and summaries of sightings data. 3.3 Recording Methods 3.3.1 Report Cards The basking shark report card has evolved considerably since 1987 in parallel with the continued development of the project. Details of sighting location have been recorded from inception, along with standard information regarding the number and size of sharks. However, changes and additions have been made to the information that is now requested based on assessment of the level of completion of different questions.

The card uses check boxes or similar where possible in order to reduce subjectivity and ambiguity, facilitate ease of card completion, and provide standardised information allowing the realisation of a set protocol for data entry. In addition, lateral and dorsal basking shark outlines are provided to enable documentation of distinguishing features on individual sharks. The recording cards also allow observers to record turtle sightings in UK waters. 3.3.2 Online (http://www.mcsuk.org) The 2001 summer season was the first year that Basking Shark Watch utilised the web to receive reports of sharks. Since then this has become the most popular method of reporting basking shark sightings.


http://www.mcsuk.org/baskingsharks.html



3.3.3 Telephone Reports received by MCS via telephone are fielded by completion of a report card in telephone communication, re-direction to the website, or a report card sent direct to the caller’s address. 3.4 Limitations of Basking Shark Watch 3.4.1 Data Characteristics Due to the nature of the methodology, information can only be gathered on the surface behaviour of the basking sharks seen and this is likely to be only a partial reflection of the behaviour of these animals.

The quality of data received varies. Analysis of the information recorded on recording cards received to1992 indicated that 74% of sightings had 9-13 information fields completed (Earll & Turner, 1992). Recording cards which lack information are followed up with a phone call in order to complete the recording card. Information on location is one of the most important fields as it allows accurate mapping of the data. In general, accurate locations are given using GPS coordinates or OS Grid references however sometimes no fixed position is given. In such cases an approximate GPS is fixed using descriptions of the location. Quality assurance of data is continuous and records containing high degrees of uncertainty and obvious errors are omitted from analysis.

Basking Shark Watch is a non-effort based, surface sightings scheme and the project data is therefore only suitable for relatively limited statistical analysis. Furthermore, the data relates to sightings of sharks at the surface and does not allow for a full assessment of the population dynamics of the species. Sharks may well be present in an area but if not seen at the surface, their presence will go unrecorded by Basking Shark Watch.

The probability of sighting a basking shark at the surface will vary according to the diel period and the surface abundance of zooplankton (Sims et al., 2003 b). Basking sharks will spend less time on the surface in areas with low abundance of near-surface plankton prey than more productive areas such as tidal fronts (Sims & Quayle, 1998). Sighting reports from these areas are therefore anticipated to be low and the probability of sightings may decrease further in the afternoon due to the downwards migration of zooplankton species in some areas (Sims et al., 2003 b). 3.4.2 Effort & Regional Bias Reports of surface sightings to Basking Shark Watch are reliant on the number of potential observers present in an area. Further, public participation is dependant on weather conditions, public holidays, dedicated surveys and the level of promotion of the scheme. Some regional bias may be present in the UK due to variable levels of regional interest in the species and uptake by local press and radio. MCS attempts to mitigate for regional bias and encourage greater UK project coverage by taking a national approach to the scheme’s promotion. Since the last Basking Shark Watch Report (1987-2001) efforts have been directed at promoting the scheme to a greater extent in areas where basking shark reports were relatively low: Wales, Ireland and Northern Ireland.

It has been previously documented that records of shark sightings in inclement weather are uncommon, and that there is often an increase in sightings following bank holiday weekends or when the weather is particularly fine (Nicholson et al. 2000). The effect of weather on sightings is probably an artefact of observer effort, as


more potential observers are generally present in fine weather, while spotting sharks in poor weather is more difficult. However, some effect may be genuinely attributed to increased ‘basking’ or feeding, a behaviour generally associated with warm, calm conditions when surface plankton concentrations are high (Doyle et al., 2005). To compensate for observer artefacts, MCS has attempted to identify regular sea watchers and observers. Contacts have been identified through several methods: their contact with MCS, web searches and magazine searches. Bird-watchers, naturalists, ferry services, fishermen, yachtsmen, divers, and the volunteer coastguard are all audiences which have been contacted to promote the project. 3.4.3 Multiple Sightings As with all non-effort based, public participation wildlife sightings schemes, Basking Shark Watch will generate “multiple sightings”, i.e. the same animal may be reported separately by different people. Since it is not always possible to identify every instance of replication, shark abundance may appear higher in some areas, particularly where observer numbers are high (Earll & Turner, 1992). Efforts have therefore been made during data entry to minimise such duplication errors between record comparison of location, time, shark distinguishing features etc. Multiple sightings, when confirmed as such, are collated as one record and are useful as they provide independent confirmation of sightings or events.

Speedie (2003) compared results from a similar public sightings scheme with effort-based surveys and found that the basking shark sightings data closely resembled that of the survey data, both spatially and temporally. Disparities did occur and were attributed to a lack of quantifiable effort, multiple counting and animal mis-identification. For example, a large shoal of basking sharks, recorded during the line transect surveys, was not reported via the public sighting schemes. Public involvement and participation in such schemes has led to increased public awareness of the basking shark, which has undoubtedly delivered opportunities for the arguments in favour of greater protection of the species to achieve widespread coverage (Simmonds, 2000). Inclusion of the basking shark in the new Countryside and Rights of Way Act 2000 is a reflection of public concern leading to Government action (Speedie, 2003). Public sightings schemes have the potential to identify areas that appear to support large numbers of basking sharks and are therefore appropriate for more detailed surveillance and monitoring (Speedie, 2003). In addition, collating public sightings provides a cost-effective means of gathering information over a much larger area than could be achieved through effort-based surveys. 3.5 Data Management & Collaboration

The Basking Shark Watch sightings database is currently in Microsoft Access format. Further detail on the development of the MCS Basking Shark Watch database is provided in the previous technical report (Doyle et al., 2005).

Data is entered into the Basking Shark Watch database using a standardised protocol and fixed positions are converted immediately into decimal latitude/longitudes and eastings/ northings. Data with accurately fixed points were mapped using MapInfo Professional 6.0.

There has been an increase over the past five years in the establishment of projects focusing on the basking shark. This highlights the need for greater collaboration between organisations, in order to maximise the use of the information gathered and outputs produced, and prevent duplication of effort. For this reason, MCS continues to collaborate and share data with many organizations, principally via the Biodiversity


Action Plan group, and the association with US researchers, French NGOs, and cetacean watching groups from the UK and Ireland.


4. Results This 20-year report covers the period from 1987, when The Basking Shark Watch (BSW) project was launched, to 2006. A total of 10,108 records were received during this period. 4.1 Geographic Distribution Of the 10,108 sighting records submitted to BSW for 1987-2006, accurate map references could not be obtained for 636 records (6.3%) due to insufficient information about the sighting location. The remaining 9,470 sighting records (93.7%) could be mapped. Sightings around the UK are plotted in Figure 4, as individual points. This map indicates high sighting densities on the west coast of Scotland, around the Isle of Man, all around the south west of England, and along the middle of the western half of the English Channel. Low sighting densities are obvious along England’s east coast, particularly in the southeast. However, the small scale reproduction of the huge area covered by this map means that considerable detail is hidden, particularly masking the difference between areas of medium and high sighting densities.

Figure 4. Distribution of basking shark sightings around the UK and Ireland, 1987-2006

(individual sightings are plotted as single red dots).


Figure 5 shows the same data, but plotted as sighting density per 10km2 grid, which gives a more useful indication at this scale without an overlap of sightings. It clearly shows the highest densities on the west coast of Scotland, around the IOM and the southwest of England.

Figure 5. Distribution of basking shark sightings around the UK and Ireland, 1987-2006

(lightest shades are 1-10 sightings; then 11-50; 51-100; the darkest squares represent densities of 100+ sightings). (Map by Steve Frampton).


4.2 Regional Analysis Of the 10,108 sighting records submitted to BSW for 1987-2006, 81 records could not be assigned a region due to insufficient information about the sighting location. The remaining 10,027 records were assigned a region (Table 1). The highest number of sighting reports was received from SW England, then Scotland, the Isle of Man and Ireland. The figures for regions around the UK are plotted in Figure 6, which clearly shows the dominance of these four regions. Table 1. Regional breakdown of all sighting reports received by Basking Shark

Watch between 1987-2006.

Country/area Region No. records UK/local SW England

SE England NE England NW England Scotland Wales Ireland IOM English Channel Channel Islands Irish Sea

4512 24 21 33

3379 45

527 1335

48 45 7

Overseas N Atlantic N Sea France Biscay Azores West Africa USA

11 3 2

24 4 1 6

- None 81 Total - 10108


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nglan

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nd IOM

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nnel

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s

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el Isl

ands

NW Eng

land

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land

NE Eng

land

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repo

rts

Figure 6. Total number of sighting reports received from each UK/local region between

1987-2006. Figure 7 shows the percentage contribution of each region to the total number of sighting records, which emphasises the significance of 4 regions: SW England, Scotland, the Isle of Man and Ireland. Sightings from these regions make up 45, 34, 13 and 5% of total sighting reports that have been attributed a region, respectively – and together, these 4 regions make up over 97% of all sighting reports. However, it is worth noting that the Scotland and Ireland regions include a disproportionately large geographic area and coastline. No attempt has been made for the regions to be comparable in that respect, and this will be one of many factors likely to influence the number of sightings a region will produce. The Ireland region has recently been subdivided into 2 new regions (Northern Ireland and Eire), to which all new sightings are now being allocated, but it has not been possible to reallocate many older sightings, for which Ireland is currently the recorded region, in time for this report. It is intended that the Scotland region will also be subdivided in the near future.


Ireland5%

SW England45%

Scotland33%

IOM13%

SW EnglandScotlandIOMIrelandEnglish ChannelWalesChannel IslandsNW EnglandSE EnglandNE EnglandIrish SeaN AtlanticN SeaAzoresBiscayFranceUSAW AfricaNone

Figure 7. Percentage contribution of each region to total sighting reports, 1987-2006. Figure 8 shows that percentage contribution, from the different regions, has varied over time. SW England, Scotland and the Isle of Man have consistently dominated the sightings distribution such that all other regions, when added together, make only a small contribution to total report numbers for most years. SW England has been the dominant region since 1987, except for a three-year period between 2003 and 2005 when a dramatic upturn in Scotland sightings coincided with a temporary downturn in sightings from SW England. The Isle of Man region has contributed two major sightings surges, between 1988 and 1992 and, more significantly, from 2003 onwards.

0

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87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06

Year

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repo

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OtherScotlandSW EnglandIOM

Figure 8. Total sighting reports per year, including regional origin.


4.2.1 Southwest England and the Channel Islands

Distribution Basking sharks are more predominantly reported from the southern coast of the southwest peninsula (Fig. 9). Regional hotspots occur at the Kingsbridge estuary mouth; the southern and eastern Lizard peninsula; Gwennap Head round to Cape Cornwall on at the Land’s End tip of the peninsula; The Mouth of the Camel estuary on the north Cornish Coast and Lundy Island in the Bristol Channel.

Figure 9: Number of basking shark sightings (by 5km2 cell) from the southwest region:

Dorset, Devon, Cornwall and the Scillies, including the Channel Islands.


Annual variation Between 1987-2006, 4,512 reports of 21,054 sharks were received from Southwest England (Figure 10). Numbers of sighting reports and sharks have varied considerably over the 20-year span of the project, with a pattern of clear peaks and troughs, but the long-term trend has been towards higher numbers of both reports and sharks. 2006 saw a dramatic increase in sightings over 2005, from 312 to 890, and also over the previous record of 452 sighting records in 1998.

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Figure 10. Annual variation in numbers of sighting reports and shark numbers, received

from SW England.


Seasonal variation Sightings increase in May, peak in June and tail-off through July to September (Figure 11). May, June and July make up 24, 33 and 21% of total sighting reports, respectively. Observed shark numbers, however, peaked in July due to a higher mean number of sharks per sighting (6.5 in July versus 4.2 in June).

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Figure 11. Seasonal variation in numbers of sighting reports and shark numbers,

received from SW England (1987-2006).

Shark size Size was recorded for 4894 sharks (23.2% of the total for the southwest). Shark size frequency showed a normal distribution (Figure 12), with the highest number of sharks in the median (4-6 metre) size range.

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Figure 12. Size frequency of basking sharks reported from Southwest England, 1987-

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4.2.2 Scotland

Distribution Basking sharks are more predominantly reported from the West coast of Scotland, particularly around the Northern Clyde Sea; northwest Mull; Coll and Tiree; West of Canna (Hyskeir lighthouse) – sharks are particularly prevalent in the inner Hebrides (Fig 13).

Figure 13: Number of basking shark sightings (by 5km2 cell) from Scottish waters. The

map includes the 12nm limit of territorial seas.


Annual variation Between 1987-2006, 3,379 reports of 6,885 sharks were received from Scotland (Fig 14). After an initial surge during the first four years of the project, there was a 10-year lull in sighting reports between 1991 and 2000. However, report numbers increased dramatically between 1999 and 2005, before levelling off in 2006.

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Figure 14. Annual variation in sighting report and shark numbers, received from

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Seasonal variation Sightings increase gradually throughout June, July and August and tail-off in October (Fig 15). There is evidently a later increase in Scottish waters in basking shark sightings than in SW waters, and the peak months for sightings are more protracted in Scottish waters, with large numbers of sharks consistently observed in Scottish waters into September (541 sightings in Scottish waters compared to 106 sightings from SW waters).

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Figure 15. Seasonal variation in sighting report and shark numbers, received from

Scotland (1987-2006).


Shark size Size was recorded for 3254 sharks (47% of the Scottish population). Shark size frequency showed a normal distribution (Fig 16), with the highest number of sharks in the median (4-6 metre) size range. There was a higher proportion of larger sharks (31%; 998/3254) reported from Scottish waters (in the 6-8m size range) than from Southwest waters where only 4% (929/4894) of that region’s population was reported from this larger size class.

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Figure 16. Size frequency of basking sharks reported from Scotland between 1987-

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4.2.3 Isle of Man

Distribution Basking sharks are typically distributed towards the southern tip of the Isle of Man, around the Calf of Man, up the southwest coast of the island, predominantly at Niarbyl Bay and Peel (Fig 17).

Figure 17: Number of basking shark sightings (by 5km2 cell) from Irish Sea / Isle of Man

waters. The map includes the 12nm limit of territorial seas.


Annual variation Between 1987-2006, 1,335 reports of 5,282 sharks were received from the Isle of Man (Fig 18). After an initial surge during the first four years of the project, there was a 8-year lull in sighting reports between 1993 and 2000, as the sightings were held by a local reporting scheme, and not contributed to the Basking Shark Watch database. However, report numbers have increased dramatically since 2005, when collaboration between the MCS Basking Shark Watch and a new project co-ordinated by Manx Wildlife Trusts was developed on the island.

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Figure 18. Annual variation in sighting report and shark numbers, received from the Isle

of Man.


Seasonal variation Seasonal variation in Isle of Man sightings shows a later initial peak than sharks entering both Cornish and Scottish waters, with high numbers reported in June and July, and numbers tailing off considerably in August (Fig 19). Shark numbers trail off considerably in September compared to Scottish inshore waters (58 sightings compared to an order of magnitude more sharks in Scotland in September – 541 sightings).

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Figure 19. Seasonal variation in sighting report and shark numbers, received from the

Isle of Man (1987-2006).


Shark size Size was recorded for 2440 sharks (46% of the IOM total shark population). Shark size frequency showed a normal distribution (Figure 20), with the highest number of sharks in the median (4-6 metre) size range, but unlike for the Southwest in particular, this was almost matched by the number of larger individuals recorded in the 6-8m size range – the size at which sharks are considered to be at breeding age. There were a higher proportion of larger sharks (32%; 777/2440) reported from Manx waters which matched the proportion of larger sharks, (31%) in the 6-8m size range from Scottish waters. Only 4% (929/4894) of the Southwest England region’s population was reported from this larger size class.

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Figure 20. Size frequency of basking sharks reported from the Isle of Man between

1987-2006.


4.2.4 Comparing size class between regions When shark size frequency is compared across the three ‘hotspot’ regions (Figure 21), we see that shark size frequency in SW England is weighted towards smaller sharks than in Scotland and the Isle of Man. Indeed the mean shark sizes (in size category 1-5 where 1=<2metres, 2=2-4m, 3=4-6m, 4=6-8m and 5=8+m) were 2.9, 3.2 and 3.4 respectively. This might indicate a separate population, or that younger sharks tend to remain in the warmer waters of SW England. Older sharks may head North to breed (in line with repeated observations from the Isle of Man of breeding behaviour by larger sharks). These sharks may be returning to SW waters to ‘pup’, and where the younger sharks remain.

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Figure 21. Shark size frequency in the different regions.


4.3 Shark size over time 4.3.1 Inter-annual variation

y = 0.0196x + 2.7851R2 = 0.2961

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Figure 22. Mean shark size per year, 1987-2006 (UK wide).

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Figure 23. Mean shark size per year in SW England, 1987-2006.


Annual Variation Observed annual mean shark size has increased over the 20 year period covered by this report (Figure 22), indicating that basking sharks are living longer, which suggests the population may be recovering from historical fishing pressure3. This recovery may be further enhanced because older fish are generally more fecund. This trend is mirrored by observed shark size in SW England only (Figure 23), but with a steeper trend line slope (0.0213 cf. 0.0196) and a lower intercept (2.6351 cf. 2.7851), indicating a more significant trend and a smaller shark size than within the whole dataset.

3 The last UK basking shark fishery ceased in 1997, when the reduced value of basking shark liver oil made the fishery commercially unviable, and the inclusion of basking sharks on the Wildlife and Countryside Act (WCA, 1981), in 1998, put an end to future options within UK territorial waters (out to 12 nautical miles). The Norwegians were still able to take basking sharks beyond this zone, through a fisheries agreement, but their T.A.C. was gradually reduced from 800 tonnes of liver weight in 1982, to zero, in 2001.


4.4 Shoal size The majority (59%) of basking shark reports were of individuals, with small schools of individuals (2-9) making up a further 34% of the sightings. Basking sharks were however fairly commonly observed in schools of 10+ individuals. It is thought that the drivers that make sharks shoal are either social or related to individuals converging at feeding hotspots. Table 2. Basking shark shoal sizes, and location. Shoal size Number of reports (%

of database) Location

1 5949 (59) Entire UK continental shelf 2 1359 (13) Entire UK continental shelf

3-9 2074 (21) Entire UK continental shelf, with dominance in SW; Isle of Man and Scottish hotspots

10-49 592 (5.86) Coll, Tiree; Clyde; Isle of Man; SW Ireland 50-99 48 (0.5) South and west Isle of Man; West and north

Cornwall; Scilly Isles 100-250 28 (0.3) South and west Isle of Man; West and north

Cornwall; Scilly Isles >250 3 (0.03) Southwest Cornwall

Figure 24. Basking shark shoal sizes. (Black dots 10-49 sharks; Yellow dots 50-99

sharks; Red dots 100+ sharks).


5.0 Discussion 5.1 Regional hotspots The database identifies three clear ‘hotspots’ for shark surface basking behaviour – The Southwest peninsula (Devon, Isles of Scilly and Cornwall); the Isle of Man (southwest and west); and west Scotland. However, as the database is not effort-corrected (the sightings may be of the same shark recorded by a number of different observers at the same time), it is not a true reflection of relative sightings densities from these regions. However, the year on year consistency by which these regions report basking sharks near to the coast would suggest that they are important locations for shark activity in surface waters. Most of the observations come from coastal walkers, and clearly identify areas where sharks are most likely to be seen near to the coast, rather than out at sea. Therefore, the database serves as a useful guide of shark activity in surface waters that abut the coast, rather than any true reflection of shark hotspots at the coast (within 1nm) relative to offshore (>1nm) sites, from where we have limited records. However, there are distinct areas of offshore waters which appear to reveal more sightings than other areas (e.g. the Hurd Deep approximately 15m northwest of the Channel Islands, and the Celtic Sea west of Pembrokeshire). 5.2 Local hotspots 5.2.1 Southwest England Sharks are frequently observed in large densities off the principal south and west Cornish headlands – those being the eastern side of the Lizard peninsula and the southwest (Gwennap Head) and northwest tip (Cape Cornwall) of Land’s End. The tidal regime, associated bathymetry and the hydrography of these areas appears to have a great influence on congregation of sharks in areas where local copepod densities appear to be highly concentrated (Speedie, pers comm.; in press). For example there is a reef at Gwennap Head which results in a small scale upwelling of currents, which leads to surface concentration of plankton at pre-determined states of the tide (www.seawatch-sw.org). Similarly, the direction of the flood and ebb tide inshore between the Lizard and Manacles appears to influence a similar congregation of basking sharks at areas of high copepod densities. 5.2.2 The Isle of Man The Isle of Man has a clear distinction between areas of high basking shark density to the south and southwest coast of the island where the Dublin front hits the southwest of the island. Sharks are regularly observed at the Calf of Man, and further north up to Niarbyl Bay and Peel. Niarbyl Bay is an area where frequent reports of courtship have been observed (see below). The larger mean size range from Isle of Man waters may indicate it is an area where sharks congregate not only to feed, but also to breed. It is thought that basking sharks reach breeding sexual maturity at sizes over 6m, and the number of sharks attaining this and greater size in Scotland, and particularly in the Isle of Man, would suggest these locations may attract a larger population of breeding adults than the Southwest. 5.2.3 Scotland The Hyskeir lighthouse just to the west of the Isles of Eigg and Canna in the inner Hebrides, and the north coast of Mull (near to the northern end of the Sound of Mull) appear to be areas where sharks are frequently observed. Effort-based surveys by


http://www.seawatch-sw.org/

the Wildlife Trusts / Colin Speedie and the Hebridean Whale and Dolphin Trust have shown regular large shoals of sharks at these locations. 5.3 Fronts The data and distribution maps show the important influence of frontal systems to the aggregation of shark activity in surface waters (Fig. 25). Research from the Marine Biological Association has identified that the frontal areas of UK / French and Irish seas over the continental shelf waters contributes to a diel vertical migration of copepod food to surface waters (Sims et al., 2006). This daytime migration of the basking shark’s principal food source is closely followed by the sharks in summer months, concentrating them at the surface waters only in areas where fronts (mixed) waters occur, which provides ideal conditions for rapid plankton growth.

Figure 25. Distribution of fronts (left) and basking shark hotspot locations (right) from

research carried out by the Marine Biological Association. (Source Sims et al, 2005).

5.4 Causes and timing of surface ‘basking’ behaviour MCS collaborated with University of Edinburgh Masters student Sarah Phenix, The Sir Alistair Hardy Foundation for Ocean Science (Continuous Plankton Recorder) and The National Oceanic and Atmospheric Administration (SST) in 2007 to investigate the onset of surface feeding behaviour of sharks in UK waters with SST and copepod abundance. The work correlated the inter-regional variability of the onset of basking shark surface activity at the three UK hotspots – Southwest peninsula; Isle of Man and West Scotland with SST and copepod abundance in the waters of these areas. The work concluded that the onset of basking shark sightings in these regions was strongly triggered by SST increasing above a threshold temperature (Figures 26 and 27). It was postulated that the temperature was the initial cue to drive the sharks’ foraging behaviour to surface waters, whereas the targeted movements towards dense copepod patches was more likely to drive their horizontal distribution at these frontal regions, once they had migrated to surface waters. The timing of the decline in surface sightings of sharks was more likely related to reduction in the densities of copepods at surface waters, rather than being linked to temperature.


Figure 26. The total number of surface sightings per month by the average monthly

mean total copepod abundance and monthly mean SST from 1987-2005 in southwest England. (Source: Phenix, 2007).

Figure 27. The total number of surface sightings per month by the average monthly

mean total copepod abundance and monthly mean SST from 1987-2005 in Scotland. (Source: Phenix, 2007).

5.5 Feeding The MCS Basking Shark Watch project records behaviours such as breaching; swimming with mouth open (feeding) and swimming with mouth closed. It is clear that the majority of observations of sharks were of sharks swimming with their mouth open to strain tiny particles of zooplankton from the water column. The sharks are clearly spending the vast majority of time in the UK spring and summer months feeding on copepod and other zooplankton concentrated in shoals in surface and near-surface waters, particularly where fronts create the necessary conditions for zooplankton to feed on phytoplankton. Reports of sharks with their mouths closed are most likely the result of them intermittently swallowing plankton accumulated in the back of the mouth.


An alternative hypothesis may be that the sharks close their mouths when disturbed by the proximity of a vessel (such as a RIB; sailing boat; ferry boat) or diver. The response of sharks to close their mouths may be to allow the sharks to swim more quickly away from any perceived threat, as their resistance of travel through the water is lessened with the mouth closed. The aperture of the mouth of a fully grown shark may be up to 2m, therefore the closure of the mouth would clearly eliminate the resistance when an escape response is exhibited. Film footage of basking sharks often shows them closing their mouths the closer they come to the camera (see footage (http://www.vimeo.com/851801) recorded by Dan Burton). 5.6 Social behaviour Many reports from the Isle of Man were of social interaction between sharks unrelated to feeding. Many sightings by an individual observer John Galpin on the west coast of the Isle of Man were of sharks ramming; echelon swimming; parallel swimming, and potentially mating. The Isle of Man Basking Shark Watch received a report in 2006 of a pool of blood followed by the emergence of a small (2m) shark with a snub nose. Small sharks with snub nose are known to be young of the year, and this report would suggest the first observation of the birth of a basking shark in the NE Atlantic (http://www.manxbaskingsharkwatch.com/2005.aspx). These intriguing social behaviours of the shark require future research and detailed description (as has been the case for other more commonly observed terrestrial fauna), in order to describe and quantify the variety of social behaviours indicating important life history stages of the species.


http://www.vimeo.com/851801

http://www.manxbaskingsharkwatch.com/2005.aspx

6.0 Conservation 6.1 European The basking sharks have received considerable media, funding, scientific and conservation interest in the past decade. It has been 10 years since the species was listed on the Wildlife and Countryside Act, yet widespread protection for the species was only achieved in January 2007, when the Common Fisheries Policy banned the landing, trade and transhipment of all basking shark parts in European waters. This legislation superseded the domestic legislation of independent European member states, which only provides protection for the species out to 12nm (which only covers a small proportion of the species range). It was MCS who compiled the Bonn Convention proposal, and was therefore responsible (with other partners) for the species being given Europe-wide protection through fisheries regulations. 6.2 Site based protection (MPAs) Some marine experts argue that the use of site-based conservation tools such as Marine Protected Areas are not particularly beneficial for wide-ranging species such as the basking shark. Given that the shark has been shown to move thousands of kilometres in 3 months (Sims et al., 2005) to source food, some say it would be ineffective to use site-based protection mechanisms in isolation from comprehensive protection under fisheries regulation. However, given that there are some sites which clearly show repetitive visits by basking sharks, we would argue that where potential dangers exist (e.g. harassment by pleasure boat craft and entanglement in static fishing gears) Marine Protected Areas could be appropriate, especially where there are other biodiversity or fisheries benefits from restricting one or more human activity in the area. MCS recommends that the following activities should be restricted in basking shark Marine Protected Areas:

• Bottom set fishing nets (pots should be allowed in reasonable densities) • Powerboating over 5 knots (jet skiis; RIBs; yachts; ‘sunseeker’ boats)


As such, MCS would recommend the following hotspots for consideration of MPA status for the basking shark:

Figure 28. MCS recommendations for basking shark MPA in southwest England:

Gwennap Head (southern Land’s End peninsula) and eastern Lizard peninsula.

Figure 29. MCS recommendation for a basking shark MPA in the southwest Isle of Man

at Niarbyl Bay.


Figure 30. MCS recommendation for a basking shark MPA off the west coast of

Scotland at the Hyskeir lighthouse. The following activities should be managed at the above locations during periods of intense shark activity in spring and summer months:

• A limit on the amount of bottom-set fishing gear (pots, creels and no set nets) • A limit on the speed of pleasure boat craft in these areas (< 5knots) • A limit on the distance of pleasure boat craft from the sharks (>100m from the

shark with the engine on) • A limit on the distance vessels should approach the shark to 4m.

6.3 Management of threat 6.3.1 Pleasure boat craft The basking shark was protected from harassment under the CRoW Act amendments to the Wildlife and Countryside Act in 2006. However, it is not yet clearly understood what constitutes harassment of basking sharks. Anecdotal accounts of behavioural changes in the social behaviour of sharks have been recorded by experienced wildlife observers on the Isle of Man (Galpin, pers. com.) when the sharks are exhibiting courtship behaviour. It appears from these detailed observations that sharks were disturbed by the approach of motorized craft up to 1km away when socially interacting and exhibiting courtship behaviour. By contrast, observations from Gwennap Head by Seawatch Southwest wildlife observers in 2007 appeared to show that the sharks only showed altered behaviour when vessels approached very close to them (within 10m).


Figure 31. Basking shark / RIB encounter recorded near Land’s End, Cornwall in 2006.

This activity by the boat handlers clearly breaches the code of conduct recommendation, which states that engines should be switched to neutral up to 100m away from the sharks. (Photo by Rebecca Hoskin).

The Shark Trust, Colin Speedie (chair of the Shark Trust, and experienced basking shark observer) and MCS have collaborated to produce a Code of Conduct (http://www.mcsuk.org/marineworld/baskingsharks/code+of+conduct) for boat users, divers and other sea users to safely interact with the shark whilst causing minimal disturbance to the animal and its natural behaviour. Furthermore, Colin Speedie has introduced the WiSE (WIldlife SafE) scheme which accredits trained participants with a certificate as a responsible wildlife tour operator. The course has been carried out in all UK and near-UK territories including Cornwall, Devon, Jersey, Ireland, Northern Ireland, Isle of Man and Scotland. A DVD is now available from WiSE.


http://www.mcsuk.org/marineworld/baskingsharks/code+of+conduct

6.3.2 Static fishing gears Static fishing gears pose a problem to basking shark protection, as they can easily entangle basking sharks with bottom set (gill and tangle net) gears, and in surface ropes for pot (creel) fishing.

Figure 32. Basking shark accidentally caught in pot ropes near Sennen Cove, Land’s

End in June 2007. (photo by Andrew Carn) Periodically there are considerable numbers of basking sharks taken in pots or Nephrops norveigicus creels (the latter generally from Scottish waters). MCS received an anonymous report of 6 basking sharks being caught in deep waters (about 180m) in creel ropes within the Clyde Sea within a 2-week period in 2006. The aggregation of sharks in areas of intense static fishing gear use can be a problem, and should be considered for site-based conservation management. For example, the area to the east of the Lizard peninsula is not only a basking shark hotspot, but also an area where fishermen set a considerable number of static gill nets (Speedie pers comm.). The fishery should consider a temporary reduction in effort when the basking sharks migrate into shallow waters. Setting a rigid timescale for the management of effort in hotspots would be problematical, as the timing of shark occurrence in surface hotspots differs between years. As such, management measures such as emergency orders could be used to control fisheries in these circumstances, when sharks reach a certain threshold density. The Cornish Wildlife Trust has previously attempted to develop a voluntary agreement between fishermen to haul in static gear in Mounts Bay when cetaceans were regularly observed at high densities. The agreement broke down because of the lack of compliance by a number of vessels (Cornwall Wildlife Trust). MCS would recommend that the effort (soak time); amount of gear (length of nets / pot strings); density of gear (amount of gear per unit space) is not only better


regulated for the benefit for individual fishermen, as it will likely result in greater catch per unit effort, but as it can also be used as means to reduce levels of bycatch of these species in seasonal basking shark hotspots.

Figure 33. Typical lobster pot array showing the surface ropes for fishermen to relocate

and haul the pots on board the vessel. It is the vertical ropes, and the loose surface horizontal flagged buoy ropes that commonly entangle sharks. (from Eno et al., 2001).

6.3.3 Mobile fishing gears There is limited information on the distribution of bycaught basking sharks by towed fishing gears, with the only comprehensive report coming from New Zealand waters (Francis and Duffy, 2002). Mobile fishing gears also periodically catch basking sharks, however this is not currently thought to be a great concern to UK basking shark populations. However, information on the number of basking sharks caught in UK and international waters is compromised by the fact that fishermen are not generally willing to report the by-catch of species of conservation concern, as they feel they may then be restricted in the grounds they are able to fish. Furthermore, as it is illegal to tranship basking sharks in EC waters, there is a further restriction on boats landing by-caught basking sharks to provide information on sex, age, and obtain genetic material from sharks.


7.0 Recommendations

• Carry out effort-based surveys on an annual basis from pre-arranged sightings locations (below) to record basking sharks and other marine megafuana:

Southwest: Gwennap Head, Cape Cornwall, Lizard peninsula, Lundy Island, Start Point, Portland Bill Wales: Skomer Island, St Govan’s Head, Strumble Head, Bardsey Island, Holy Island (Holyhead) Isle of Man: Calf of Man, Bradda Head, Niarbyl Bay, Peel Scotland: Mull of Galloway, Mull of Kintyre, Coll /Tiree, Colonsay, Mull, Canna, Barra, Lewis, Skye (Neist Point),Cape Wrath, Fair Isle, Orkney, Shetland. • Recent information has highlighted that the UK basking shark population may

also be part of not only a wider northeast Atlantic population, but may indeed be part of a wider north Atlantic population, as a shark was tracked moving from the Isle of Man to Newfoundland waters in summer 2007 (Gore et al., 2008). Therefore MCS recommends that the species requires a north Atlantic MoU under the auspices of the Bonn Convention to undertake further collaborative research on the population, including further analysis of population genetics.

• Wildlife-watching operations should receive obligatory WiSE accreditation,

before being given a license to operate. • Awareness of the Basking Shark Code of Conduct and its application needs

to be promoted to recreational boat users.

• Professional wildlife-watching operators breaching the code of conduct should be reprimanded by the police, and where they are WiSe accredited, should have their accreditation removed.

• Sea Fisheries and Conservation Authorities (Sea Fisheries Committees prior

to the Marine Bill being passed through parliament) need to introduce bylaws to control the quantity and location of bottom-set gill nets during periods and in areas where basking shark densities are greater than 5 per square kilometre per day in any given location.

• Unlicensed recreational craft recklessly disturbing basking sharks (by

approaching within 10m of sharks at speeds greater than 10 knots) should firstly be issued with a warning, and secondly prosecuted under the terms of the Wildlife and Countryside Act amendment under the CroW Act to avoid harassment to the species.


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