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Gronant Little Tern Report 2014

Denbighshire County Council Countryside Service

Gronant Dunes

Little Tern (Sternula albifrons)

Breeding Report 2014Compiled by

Alec Holton, Tom Hiles, Andrea Kelly-Lansley and Andy Farrell

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Executive Summary

This is the tenth Gronant tern report to be produced by Denbighshire County Council Countryside Service. There was positive news from the 2014 season with the number of breeding pairs up to 136, an increase again on the previous year. The productivity results were reasonable with 77 little tern young successfully fledged this year. However, the five year breeding average for next year is likely to drop below the sustainable level for the first time since 2002, even when considering a productive breeding season in 2015.

The staffing levels were the same as in recent years with three little tern wardens employed for the breeding season, two four-month posts and one three-month post. Once again we need to thank Natural Resources Wales and Haven Leisure for their crucial funding to the protection scheme. The start dates of the wardens were late this year with an additional post, detailed below, delaying the recruitment process considerably. On a positive note, this meant more time later on in the season to prepare a warden handbook and consider improvements to our management of the tern colony.

Predation during the season was a problem with fox and kestrel being the main culprits again this year. With no overnight warden scheme in place then exact numbers predated by fox is always going to be difficult to ascertain but we estimate around 70 nests were taken this year. The trail camera that was set up this year provided good evidence in recording egg predation by fox during the period of dusk till dawn. Worryingly a full clutch of eggs was taken from under the electric netting this year. This is the first record of fox predation within the mesh style electric fencing, which was introduced back in 2002. Kestrel predation on the other hand was similar to previous years with one adult little tern taken and a total of 22 chicks and two fledglings predated. The number of losses would certainly have been a lot higher without the great support from volunteers who gave a total of 643 hours at the colony this year, involving lots of time chasing kestrels!

The little tern protection scheme in place at Gronant has undergone many changes over the years. Initially, a weekend wardening scheme was put in place from 1969 and a simple roped off area around the nesting terns gave some protection from human disturbance. This has evolved into the current protection given by three tern wardens and volunteers, with two kilometres of rope limited access and six pens of electric fencing. This proactive approach has been a success in maintaining a population of little tern in Wales.

The inability to re-establish those areas lost elsewhere in Wales though should still be a cause for concern. The five year LIFE+ Nature little tern recovery project entered its first breeding season this year. The project is a partnership between the RSPB and nine other organisations across the UK including Denbighshire County Council. It aims at increasing knowledge of little tern habits through a colour ringing project and improving management strategies of the tern colonies at the key breeding sites. With the grant funding we were fortunate to be able to employ a new temporary member of staff for the 2014 season. Andy Farrell took on the role of Little Tern People Engagement Officer for a five month period and proved to be an extremely valuable addition to the team. He was critically involved in implementing new methods to protect the colony, helping boost volunteer numbers and organising a very successful end of season event that we now hope to repeat in following years.

Adrian Hibbert, Countryside Warden

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Contents Pages

Cover Page 1Executive Summary 2Contents 3

1.0 Introduction 41.1 Key dates

2.0 Site Overview and Equipment 52.1 Fencing2.2 Signs2.3 Chick Shelters2.4 Other Equipment

3.0 Breeding Success 83.1 Nest data and marking 3.2 Adult Little Tern Counts3.3 Chick and fledgling productivity3.4 Further Study

4.0 Predation 134.1 Fox (Vulpes vulpes)4.2 Kestrels (Falco tinnunculus)4.3 Other Predators

5.0 Weather and Tides 185.1 Weather5.2 Tides5.3 Temperatures

6.0 Human Disturbance 216.1 Walkers6.2 Birdwatchers and photographers6.3 Light aircraft and pleasure kites

7.0 Beneficial Disturbance 227.1 Nest moving7.2 Chick ringing7.3 Licenced photographers

8.0 Recommendations for 2015 239.0 Acknowledgements 2410.0 Appendices 25

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1.0 IntroductionThe following report details the breeding success of the Little Tern (Sternula albifrons) at Gronant, North Wales in 2014.

In brief, the project was reasonably successful documenting the best breeding season since 2010. 229 little tern nests were marked from an estimated 136 pairs and a minimum of 77 birds fledged. The resultant productivity figure was 0.57 (fledglings per pair per year), slightly higher than the UK average of 0.51 but falling short of the targeted 0.70 required to maintain a stable population size (Cook and Robinson 2010); this deficit was mainly attributed to fox predation.

An estimated 70 nests were subject to fox predation and it is unclear how many chicks were taken over night. The vulnerability of the colony to foxes was attributed to the configuration of shingle that was rearranged by storms in Febuary2014. Subsequently, a considerable proportion of shingle attractive to nesting little terns was too low on the beach not to be inundated by high tides. In an effort to prolong its integrity, the electric fencing could not be used lower down the beach, and indeed the fencing was inundated by spring tides in July.

Kestrel predation was also a significant factor limiting breeding success, responsible for the loss of a minimum 22 chicks, 2 fledglings and 1 adult. However, it did not have the same impact as in, for example, the 2012 season when an estimated 70 chicks were taken.

In many ways this was a successful season with clement weather enabling prolific breeding. Temperatures were higher and rainfall lower than the monthly averages for 1980-2010, allowing many Terns to re-lay following the loss of their nests, leading to total of 229 nests for the season, a considerable amount and testament to high nest losses early in the season.

One clear success was the enthusiasm and commitment from the volunteers. They contributed 643 hours of their time, which meant that the colony was better monitored, well protected and all together more rewarding for those involved.

1.1 Key Dates06-09/05 Pens and Perimeter fence constructed27/05 Wardens on Site10/06 All Pens electrified02/06 Nest marking begins08/06 First recorded egg predation14/06 First chick recorded18/06 First chick predated by Kestrel28/06 First fledgling recorded03/07 Last LT nest marked14-16/07 High tides breach pens17/07 Highest single Fledgling count ~7025/07 Peak count of adult terns (~500)08-09/08 Final deconstruction of pens and site clearance

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2.0 Site Overview and Equipment

2.1 FencingWardens’ contracts were late in starting, so the construction of the pens and perimeter was carried out by Denbighshire Countryside Service staff and volunteers during 06-09/05. Following this certain aspects of assembling the fences were completed by Peter Milner who volunteered at the colony for several days alone. Once the Wardens were on site the fences were electrified, during the period 28-29/05. (For further detail of how this was carried out, please reference the Warden’s handbook and the 2011 Little Tern report).

Initially there was no voltage tester to ascertain the strength of the pens, but from the 6th of June recordings were taken.

Pen 1 2 3 4 5 6 7Average Voltage(KV)

1.77 3.45 2.31 3.49 8.02 5.46 1.67

Figure 1: 2014 Mean pen voltages (kV)

To provide adequate deterrent to predators electric fencing should maintain a minimum voltage of 5KV, but this was not the case for the following reasons; wardens did not receive adequate training on fence maintenance or time at the beginning of the season to improve the pens voltages, for example by removing offending marram grass; some pens were incorrectly connected to one another, creating circuits too large to be effective; 2 or more batteries were past their best this season and were not providing sufficient power; several of the earthing stakes were old and corroded leading to poor earthing; portions of the electric fencing are aging and need replacing; and pens 1 and 7 were supporting additional length of fencing in an effort to protect chicks . However, it is worth reiterating that the electric fencing at Gronant is erected to a high standard and proved successful i.e. no tracks of any terrestrial predator were seen within any of the pens.

There were 7 pens, as in 2012, but in a slightly different layout following rearrangement of the shingle. Pen 3 was to the west of Pen 4 rather than behind it, and at the beginning of June surplus electric fencing was used to try and cordon off the sand dunes behind pens 1-4. This was in 2 sections, one from the west end on Pen 1 to the picket fencing around the warden’s’ hut, and second section from the hut to the west end of pen 7.

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Figure 2: 2014 Pen Layout

Overall there was generally little debris caught in the electric fences, apart from when the colony was inundated with the high tides of the 15th of July. As these tides entered the front of pens 1-4 and submerged pens 5 and 6, they deposited a considerable amount of rubbish. A special request was made to the volunteers for extra help, and with their assistance the pens were quickly cleared, which meant that the voltage of the fences was only briefly compromised.

Outside the pens and encompassing the salt marsh behind the beach front, was a perimeter boundary rope. This marked the absolute minimum distance for the public to keep away from the pens. Ideally on the beach side the perimeter rope would be further away, but it would then be too vulnerable to the tides.

All the fence posts were topped with a 9 inch nail to discourage birds of prey perching on them, and this was on the whole successful, however there were a few occasions when Kestrels were observed on them. Perhaps next year attaching some sort of streamer to the nail, as in previous years, would increase its effectiveness.

2.2 SignsEvery 3rd perimeter post had signs attached advising the public to keep their dogs under control and not to disturb the colony. This year an additional four signs were placed around the viewing platform overlooking the beach, warning of chicks on the beach, requesting volunteers and providing further information. Also, between Presthaven Caravan Park and the viewing platform there were 3 information boards about the Little Terns. The impact these signs had in diminishing human disturbance is hard to estimate, but is not thought to be insignificant, and 1 volunteer was recruited as a result of the advertisement poster.

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2.3 Chick Shelters Approximately 100 Chick shelters were placed in all the pens in early June, with the exception of pen 7, where no Little Terns nested. The majority of shelters were deployed in the pens with highest proportion of nests I.e. pens 4 and 5. They were positioned with their backs facing the prevailing North Westerly winds. Even so, after significant periods of sand blow some shelters required emptying or moving due to sand drifts. As the season progressed some shelters were placed on the shingle outside of pen 4, but still within the boundary rope, as there were both nests and chicks in that area. For further detail about the purpose and use of the chick shelters, please reference the monitoring and breeding section.

2.4 Other EquipmentAs a fox deterrent, 5 plastic insulation posts were installed at intervals in the dunes behind the colony, adorned with CDs and twinned with solar lamps. In addition a scarecrow was built behind Pen 4 to try and discourage the Kestrel.

Around 15 x 2’ foot wooden stakes were used to mark the common paths around the site, such as the way in to the hut. This made access obvious to new volunteers, minimised the disturbance to the salt marsh habitat and helped with avoiding the wetter areas.

A leaflet box was attached to the viewing platform, with the leaflets enclosed describing the colony. This had to be regularly replenished as many members of the public were taking them with interest.

A lockable aluminium hut was positioned in the dunes behind pen 2, giving it a good vantage point over most of the site. It provided shelter for the wardens and volunteers during bad weather and housed equipment. This season its age was apparent and its size was not always adequate, particularly when accommodating volunteers. Therefore a new shelter for next season is being proposed. Stored within the hut were:

3 Hawke 8x42 (Nature Trek) waterproof binoculars and 1 Hawke 8x32 (Trek/Frontier) Binoculars

1 Leica Scope and tripod 1 Wildlife hide – this was unfortunately damaged irreparably early on by strong

winds. 1 portable shelter Starting pistols and ammunition Air horns and canisters Whistles Raptor Kite 3 two-way radios (one of which did not work) Tools and spare parts for fence maintenance and removal including; 1 Leatherman, 2

hammers, 2 screwdrivers and 1 post driver

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1 handheld infrared thermometer 150+ 9inch bamboo cane nest markers First aid kit 3 Nokia mobile phones and chargers Species identification guidebooks Litter pickers and bags Suspicious character description sheets Extra waterproof clothing and work gloves A Moth trap (introduced on 28/07 and bulb broken during construction) Various recording sheets, folders, 1 clipboard and pens

Several starter pistols and air horns broke during the course of the season but there were always enough scaring devices for both the wardens and volunteers. However, occasionally they refused to function just when a Kestrel was flying in, slowing the response of the wardens.

Also, this year the scope and tripod were fixed, greatly aiding fledgling counts and general observations.

3.0 Monitoring and breeding success 3.1 Productivity; quick reference

First nest recorded 27/5/14 First chick recorded 14/6/14 First fledgling recorded 28/6/14 Peak adult count ~500 136 nesting pairs 229 nests marked 515 little tern eggs found Peak chick count ~29 Peak fledgling count ~77 Productivity 0.57

3.2 Nest data and markingDue to the late start to the season nest marking did not begin until the 27/05, the first week of marking (27/05-02/06) yielded a total of 11 nests with a peak weekly count of 125 new nests from the 3/06-10/6 (see fig 3). The weekly number of new nests marked gradually decreased over the next few weeks but a slight increase from the 19/06-02/07 (see fig 3) could possibly indicate a period of re-lays on site.

The majority of successful nests were predominantly inside the electrified pens, however at least one nest outside the electrified fence hatched. This nest was located towards the western end of pen 1 almost near the perimeter fence, upon discovery of this nest the boundary fence was extended to limit disturbance to the incubating birds.

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Nests were marked as in previous years with colour coded bamboo canes, with a series of electrical tape wrapped around them. This was useful to keep track of the fate of the nest and could be easily identified from a distance using the scope to limit disturbance to the colony. A total of ~136 nesting pairs were present at the colony this season which was an increase of 7 breeding pairs from last season.

The majority of nests were marked by observing adults returning to their nests, using a spotting scope from the beach. Warden were granted with ‘loose responsibility’ of two particular nests at the start of the season (each with a 2 pen gap i.e. 1&4, 2&5, 3&6), and this factored for a deeper understanding of nest location within each of the pens and thus made it easier when conducting the LIFE+ nest monitoring.

Due to the large quantity of nests the coloured pegs began to run short, this resulted in the pegs having to be re-used on several occasions. This made record keeping difficult when analysing data as in some cases the same peg was re-used in the same pen.

Record keeping in regards to nest fate needs to be worked on for next season, possibly including a more comprehensive description of factors that affect the nest such as predation, high tide etc. and specific dates these occurred on.

It is suggested more bamboo canes be made available for next season, or a new method of nest marking be developed to encompass the large amount of paper work into a single, user friendly database.

This will give a more accurate representation of the total nests present at the site at any particular time over the course of the season.

Chick shelters were placed roughly 60cm away from nests. Chicks were observed inside the shelters during periods of high winds as cover against sand blow and also cover against avian predators. Tracks were seen frequently leading in and out of the shelters. Chicks were also seen resting up against the shelters during sunny days.

Chicks were likewise observed utilising other unusual objects as refuges for shelter, such as beer cans and similar debris washed up by the tides, old tyres at the end of the shingle spit and an old pallet was trialled and proved popular. This is a good example of the chicks displaying a diverse adaptability to their surroundings.

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27 May-2June

3 June-10 June

11 June-18June

19 June-25 June

26 June-2 July

3 July-10 July

11 July-18 July

19 July-26 July

27 July-2 August

020406080

100120140

Date (week)

Num

ber o

f Nes

ts M

arke

d

Figure 3: Number of nests discovered and marked per week 2014.

3.3 Adult little tern counts Daily peak counts were quite steady from the 28/05 with an average adult count of 189.14 a day, with two troughs on the 17/06 and 22/06 (see fig 4). This was simply due to adverse weather conditions on these dates where it was impossible to go to the beach to observe the adults to reduce disturbance.

Peak counts of the season can be seen on the 25/07, with ~500 individual adults observed. This may be attributed to an influx of adults from other colonies up the coast, as around this time the Ayres colony on the Isle of Man reported a drop in the number of adults present at their site. Peak counts dropped to ~160 birds on the 26/07but rose to ~470 birds on 27/07 and ~300 birds on 28/07, after these dates adult numbers gradually dropped to only 5 individual birds observed, these adults had re-laid later in the season and were still rearing chicks up to this point.

28/05 04/06 11/06 18/06 25/06 02/07 09/07 16/07 23/07 30/070

100

200

300

400

500

600Daily Peak Adult Counts

Date

Num

ber

Figure 4: Daily counts of adult little tern at Gronant, 2014 (individuals).

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3.4 Chick and fledgling productivity Due to a mild and warm summer (see section 5), adult incubation and chick production was very prolific. First chicks were observed on the 14/06/14 with a total of 17 chicks being counted that day, the peak count of ~29 was observed on the 17/07/14, with visual sightings gradually decreasing from that point (see fig 5), as expected chick counts decrease fledglings increase roughly around the 4/7/14.

After the 08/07/14 chick sightings began to decrease with a plateau hovering around 5 for the remainder of the season. The first fledglings were observed on the 28/06/15 with a gradual increase over the preceding weeks leading to a peak count of 70, we estimate a minimum fledgling count of 77.

28/05 01/06 05/06 09/06 13/06 17/06 21/06 25/06 29/06 03/07 07/07 11/07 15/07 19/07 23/07 27/07 31/070

20

40

60

80

100

120Daily Peak Fledgling Counts

Date

Num

ber

Figure 6: Daily fledgling counts 2014

While the data shows a peak count of 107 fledglings, this actually coincides with a report from the Isle of Man noting an absence of fledglings at their colony a few days previously, as this coincides with a large count of fledglings and adults at Gronant, it can be a fair

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28/05 01/06 05/06 09/06 13/06 17/06 21/06 25/06 29/06 03/07 07/07 11/07 15/07 19/07 23/07 27/07 31/070

5

10

15

20

25

30

35Daily Peak Chick Counts

Date

Num

ber

Fig 5. Distribution of daily Little Tern chick counts at Gronant 2014


assumption that the spike could be the result from the arrival of birds from other colonies, however it could also be the result of birds that had fledged from Gronant earlier in the season returning to roost before migrating.

As with any visual observation study the recorded data does not necessarily reflect the accurate number of chicks and fledglings at any one time, as chicks had a habit of hiding in the marram grass to the rear of the pens it was difficult to spot them from the beach.

The fledgling count is also open to interpretation as a fledgling was spotted at the Baltray colony in Ireland on the 9/07, at a time when the Irish colonies had no records of Little Terns on that breeding schedule. It’s possible that some early fledged birds from Gronant could have distributed around the Irish Sea, which may aid in explaining inconsistencies in fledgling counts throughout the season. It also confirms the difficulty in recording accurate fledgling results from ‘one’ colony.

Two Little Tern fledglings found on 09th July 2014 by Niall keogh (Birdwatch Ireland) in Baltray Co Louth, Republic of Ireland. Credit: Niall Keogh

3.5 Further studyThe LIFE+ project data was introduced this year resulting in a plethora of new observational data studies being conducted over the course of the season (see LIFE+ Monitoring Introduction and Methods document). With an improved emphasis on volunteer involvement this season, volunteers were encouraged to perform the data collection tasks when they were present. Some of the new data collection objectives were;

Daily temperature and weather log. Daily high tide log. Daily brood counts. Timed predator watches. Predation and disturbance monitoring. Chick ringing.

While this data will be very useful in determining the future success at the colony, it could do with refining. Possibly including the most relevant data on one sheet, or expanding the

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daily shift report forms to include the majority of the data for the life+ project for ease of data analysis at the end of the season.

Volunteers Huw Jones and Robin Hemer obliged to conduct a small side experiment devised to ascertain the rate at which adults brought food for their chicks. A nest containing chicks was observed for one hour and a tally was kept on how often the parent bird returned carrying food and on average parents fed their chicks once every 20 minutes. It would be interesting for this experiment to be continued in proceeding seasons and could aid with Prof. David Norman’s chick growth rate data.

A second study was conducted to investigate whether the level of nest decorations little terns use is for a practical purpose, such as maintaining temperature within the nest for a longer period when the adult is disturbed and is unable to incubate.

In previous years scrapes have been seen to contain shell fragments and small pebbles, temperature readings were carried out across the site while performing other jobs within the pens such as nest marking, chick shelter placement to limit disturbance to the colony, more data needs to be collected to determine if there is a positive correlation between temperature and nests containing extensive decoration; see appendix for a full write up on this project.

It might also be worth keeping comprehensive guides of injured birds found at the site, especially considering the volume of off-shore development taking place in the area. A total of eight different birds were recorded as being injured this season, a greater black backed gull, sandwich tern, two gannet’s, common scoter and two lesser black backed gulls.

Also maybe look into collecting data on water quality over the season, this year the marine conservation society’s Good Beach Guide listed the water quality at Gronant dunes as Mandatory (minimum water quality), stark contrast to the past five years listing as Recommended (excellent water quality).

4.0 PredationA number of predators were observed at Gronant this year, including; Kestrel, Peregrine, Sparrowhawk, Merlin, Stoat and Fox. Of these the main protagonists were once again the Kestrel and Fox, with the latter having a serious impact on the breeding success of little terns.

4.1 Fox (Vulpes Vulpes) During the winter of 2013-14, storms reconfigured the shingle in such a way that many terns nested low on the beach, outside the protection of the electric fences, leaving their nests vulnerable to fox predation. 70 nests, out of a total of 229, were predated outside the pens, with the area around Pen 4 hardest hit, losing 27.

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These nests are assumed to have been victims of Fox predation because their tracks were observed regularly by wardens (17 recorded instances). The tracks often circled the pens and in some instances there were clear signs that a nest had been predated, such as broken fragments of shell. A fox had been hunting in the dunes where chicks are known to shelter. Twice a fox was spotted leaving the site at around 4am, and on one occasion a Vixen and Cub.

A new initiative this year was the presence of a trail camera on site, positioned adjacent to active nests. This captured a fox passing the pens on at least 3 occasions and actually in the act of predating one nest.

A Red Fox Captured with a Bushnell trophy cam in the act of predating a Little Tern Nest : Credit Andrew Farrell

In recognition of the Fox’s potency, additional electric fences were erected behind pens 1 – 4 in early June, however this area was left open at one end and fox tracks were subsequently observed inside. If next year this area was fully encircled it would properly

As the fox operated when the wardens were off duty, 24 hour wardening has once again been suggested to try and discourage the fox. How effective this would actually be is debatable given the size of the colony as it could well require 2 or 3 people to adequately protect the terns during the hours of darkness.

Lethal control of the local fox population prior to the season has also been discussed; This requires significant thought and investigation prior to any action being taken. It could be the case that soon after a cull a new fox would move into the area, and there is also the public relations aspect of such action to be considered.

Hopefully by next year the low lying areas of shingle will have developed sufficiently to be enclosed within the electric fences, because at no point this season were fox tracks observed within the pens.

4.2 Kestrel (Falco tinnunculus)Kestrel predation was a significant limiting factor of breeding success, but didn’t approach the levels of 2012. In that year a minimum of 44 chicks were recorded as predated, with an

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upper estimate of 70 (Gronant Little Tern Report, 2012). Similarly as many as 40 chicks may have been taken in 2011, from a minimum of 23 (Gronant Little Tern Report, 2011).

In 2014, from 27/05 to 10/08, the Kestrel was seen 167 times and was over the colony itself on 128 of those occasions. 55 attacks were observed (where a kestrel was seen diving or landing within the colony), with 25 kills in total. This year’s comparatively limited losses were partly due to the efforts of the wardens and volunteers in deterring the Kestrels. When attempted, chasing the kestrel away worked 93% of the time. The methods employed included starter pistols, air horns, whistles and shouting whilst running towards the Kestrel.

Of these the starter pistol was generally the most effective, while the whistles had some impact when introduced in July. Also, very late in the season during limited kestrel presence a kite mimicking a bird of prey attached to a telescopic pole was tested, the results were inconclusive but it is worth testing again.

Figure 7: Kestrel sightings and Predation 2011 to 2014.

The strong volunteer presence was a key factor in the successful protection of the colony. They contributed 643 hours and were present on 66 days out of the 75 days wardens were present. They were often deployed at the opposing end of the colony to the warden, both as a presence to discourage the Kestrel and a more immediate first repose to an attack. Analysing the data from the number of volunteers present this season, to the number of weekly kestrel sightings/kestrel attacks, a chi-square test of association shows a negative correlation (see below) between volunteer presence and successful kestrel kills. I.e. the more volunteers present, the less successful the kestrel was at predating the colony.

Chi-square= < 0.001

1.48E-73

However, the kestrels still managed to take 22 chicks, 2 fledglings and 1 adult during the course of the season. In the majority of these instances the Kestrel had made a successful kill and was on its way to the sand dunes at the rear of the colony before it was spotted. This was due to its stealthy approach, employing many and varied lines of attack. Although their attentions were focused mainly on pens four and five, i.e. the busiest pens, they were observed flying in from all directions, at varying altitudes, sometimes pausing to hover over the pens, whilst at others diving immediately.

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2014 2013 2012 2011On Site 153 46 262 183Attack 55 7 164 0Chick Predated 22 2 44 23Fledgling Predated 2 1 0 0Adult Predated 1 1 1 0


0

20

40

60

80

100

120

140

Chick Sightings Kestrel sightings

Date

Freq

uenc

y

Figure 8: Incidence of Kestrel sightings corresponding to chick sightings

Of the recorded attacks 54% were on Pen 4, which is unsurprising given that 44% of total marked nests were located there. Also, during the course of the season Kestrel activity varied in positive correlation to the rise and fall in chick numbers (See Figure 10)

The exact location of kestrels nests is still unknown, however it was frequently noted that post incursion the Kestrels commonly retreated to the dunes rear of the colony and frequently in the direction of the Gronant hillside. It was predominantly the male that was hunting, accounting for 69.7% of the recorded sightings.

On 17/07, 5 Kestrels were observed at once, an adult male and female with 3 juveniles. Suggesting they had a successful breeding season and yet not been the predation problem of previous years, one can assume that there were good food sources elsewhere. Particularly towards the end of the season, the kestrels were observed hunting successfully over the back dunes and rarely attacking the colony. Alternative food availability for kestrels has been reported from other Little Tern colonies this year, some with zero recorded kestrel predation incidences (Spurn Birds Observatory and Long Nanny for example)

There were on average 2.2 Kestrel sightings per day, and there were certain peak times of Kestrel activity (See Figure 9), such as early morning, midday and the early evening.

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4:005:00

6:007:00

8:009:00

10:0011:00

12:0013:00

14:0015:00

16:0017:00

18:0019:00

20:0021:00

22:0002468

10121416

Time

Freq

uenc

y

Figure 9: Temporal Distribution of Kestrel sightings


4.3 Other Predators1 Adult Tern was taken by a Sparrowhawk and another had a narrow escape.

Peregrine falcons were seen 5 times this season but they did not attempt to predate any adults or chicks, concentrating instead on other birds on the beach. Their presence was somewhat unsettling for the colony, but compared to 74 sightings in 2012 and two predation events in 2013, their impact was minimal.

Crows were seen daily on site, and although they were not observed to predate any nests they were frequently chased off as a precautionary measure.

The Little Terns mob any Gulls that fly over the colony, but historically they have not been a problem in terms of predation at Gronant. However, a Greater Black-Backed Gull did predate 1 Little Tern Chick. This is thought to be opportunistic rather than active predation and should be monitored in the future.

On one occasion a stoat was observed on site and tracks from various rodents, hedgehogs, Otter and other mustelids were seen. Although at no point were these tracks seen within the pens, there was one adult Tern found dead in Pen 4 that was unlikely to have been predated by a raptor.

There were consistently at least 5 Grey Herons in the lagoon further back in the dune system and several times one or more of these were mobbed by the Terns at the East end of the colony. Occasionally, again as a precautionary measure, they were chased away.

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5.0 Weather and Tides

5.1 WeatherThe weather conditions were generally favourable during the breeding season (May-July), as illustrated in the following maps. Although Rainfall during May was 175% to 200% of the average for 1981-2010 (fig.10a), during June and July it was lower, at 50 to 75% (fig.10b) and 75 to 125% (fig.10c) respectively.

Figure 10. Met Office 2014 Rainfall Anomaly maps for a. May b. June and c. July (% of 1981-2010 average)

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a.

c.

b.


On 07/06 there were strong winds throughout that day, causing significant sand blow, responsible for approximately 9 abandoned nests. These nests were located in particularly sandy areas on the shingle ridge and the 5 nests lost from in front of Pen.2 were also in a slight depression, making them more susceptible.

A recommendation for next season would be a weather station on site, or at least better recording of the conditions, as the weather at the colony can often feel to have a microclimate of its own.

5.2 TidesFollowing the violent winter storms of 2013-14, much of the shingle ideal for nesting was relatively low on the beach not to be inundated by spring tides above ~8.5m. In an effort to maintain the integrity of the fencing these nests could not be enclosed within the electric or in some cases the perimeter fences. For this reason much of the ‘new’ shingle spit that had formed at the East End of the colony was unprotected, leaving it vulnerable to predators, and at least 1 nest was washed out in this area.

In mid-July there was a series of high tides, peaking at 10.3m on the 15th, which entered the front of pens 1-4 and completely submerged pens 5 and 6, resulting in the loss of 5 nests from pen 5. This high tide also deposited a large amount of debris which had to be cleared to maintain the integrity of the electric fences.

From 20/06, with the introduction of LIFE+ monitoring paperwork, a High Tide log was kept, and an average high tide of 8.37 recorded.

5.3 TemperatureFrom the 20th of June, with the introduction of LIFE+ paperwork, temperaure recordings were taken with a digital infrared thermometer. The maximum temperature recorded was 30.5°C, at 13:00 on 24/07, whilst the minimum was 4.7°C at 04:30 on 24/06. These values refelct how varied conditions can be at the colony, which is, to an extent, a feature of its microclimate.Next season a more regular, standardised temperature recording system throughout the season would be beneficial, providing a clearer picture of the weather on the beach.

The following maps illustrate the monthly average temperature at the colony in 2014, in comparison to the 1981-2010 mean. Throughout the season, temperatures at Gronant were 0.5 to 1.5°C higher than the 1981-2010 anomaly (fig. 11) ; again demonstrating favourable conditions for Little Tern breeding

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20

b.

Figure 11: Met Office 2014 Mean Temperature Anomaly maps for a. May b. June and c. July (% of 1981-2010 mean)


6.0 Human disturbance

6.1 WalkersGronant and Talacre is a popular holiday site for holiday makers and beach goers. Not many incidents were recorded of members of the public venturing into the perimeter fence, a few isolated incidents but most were compliant when approached by the wardens requesting them to keep their distance. On one occasion two people were discovered within the perimeter fence resting on a large piece of drift wood causing severe disturbance to a nest only 3m away. Dog walkers likewise, there were a few incidents where dogs intruded into the perimeter fence but after requesting the owners keep them under closer control until they were further away from the colony seemed to do the trick.

Perimeter walks were useful in recruiting new volunteers and greeting members of the public, and the leaflet distribution box at the viewing platform was respectfully used and required replenishing frequently. New signs were erected at the base of the viewing platform giving an idea to walkers and beach goers of what is being done at the site. These can be found on the Brickfields Pond IT system.

A specific sign at the viewing platform informing the public to keep a specific distance from the perimeter fence for next season might be useful, it has also been suggested to erect a movable perimeter fence for the 2015 season to move members of the public further down the beach during periods of low tides.

6.2 Bird watchers and PhotographersThe majority of human disturbance was caused by photographers and bird watchers unwilling to comply with the warden’s requests to move further away from the perimeter fence, in some cases sitting up against a fence posts to take pictures.

On three occasions photographers walked into the perimeter fence even up to the electric fence and were unwilling to leave, only with persistence from the wardens and volunteers did they eventually comply and in one case only with the threat of legal action. On this occasion a report was filed with North Wales Police but no action was required. This however was a minority, and in no way stereotypes the general good will of the majority of bird watchers that were encountered over the course of the season.

It would be an advisory measure to possibly have a poster on the board walk or on the pens describing the conservation status of little terns in detail as a point of reference for wardens in the future for the more difficult individuals and have a laminated copy of the license agreement to produce if verbal requests are ignored.

6.3 Light aircraft and kite landboardingThere were a few incidents of light aircraft causing disturbance, such as planes flying low over the colony, the police helicopter and micro-lights flying too low over the colony causing

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the birds to leave the nest, while these incidents are short lived it was becoming quite frequent during spells of good weather.

This season also saw an increase in the number of power kites being used in front of the colony with two cases being documented with the kite actually over the colony; unfortunately it is difficult to deal with these kinds of disturbance as the kite is traveling too fast to approach safely to talk to the person using it.

6.3 Litter

7.0 Beneficial disturbance

7.1 Nest MovingAlthough the season was favourable in terms of warm temperatures and low tides there were several nests that needed to be moved closer to the pens. Some nests were very far away, even outside of the perimeter fence. And with the build-up of the new shingle spit which was ideal nesting habitat we had several birds nest in undesirable locations.

The wardens evaluate every situation in regards to the necessity in moving nests, if there is a small chance of saving the nest before the next high tide then it is only moved on days with favourably warm conditions, and only about 30cm twice a day, unless there is a high tide imminent, then a judgement is made in regards to possibly several movements a day as the nest will be washed away by the tide and lost regardless.

Of the many nests that were outside the pens, at least four were successfully moved inside over the course of the season. Both of these nests successfully hatched and produced fledglings.

In regards to nest moving it is open to interpretation on whether or not the nests should be moved or not. By moving a nest it could be the case that we’re simply prolonging the inevitable, and by allowing the nest to be lost earlier will it encourage the birds to re-lay in a more suitable location, either further up the beach or inside the electrified fences?

7.2 Chick ringingProfessor David Norman continued to study the colony in his 32nd year of holding a Schedule 1 licence to ring the Little Tern chicks, making three visits to Gronant in 2014. These were relatively late in the season (3, 10 and 15 July) so few chicks were found and only 14 ringed. Their biometric data showed that the chicks that hatched in July were somewhat lighter than normal, presumably from first-time breeders or re-lays after adults lost their first nest. But the older chicks were growing quickly and well up to normal weights, suggesting that their parents were having no difficulty in finding sufficient food.

A renewed emphasis in Colour Ringing little terns in the UK and Ireland has already come to fruition as a ‘2014’ juvenile was discovered at the Hilbre Island Bird Observatory with a Green ring on the right tarsus, indicating that it was ringed in Kilcoole, Co Wicklow. This

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further complicates the dispersal of Little Terns around the Irish Sea, and also supports the suggestion that the Dee Estuary is an important migratory route for the species. In the UK the LIFE+ Project has trialled the colour ringing programme in the south east of England this year using black on yellow rings starting with the letter U. A colour ringing report is due for release during winter 2014. Black on Yellow rings have also been used on the Isle of Man this year, resightings are unknown.

Colour ringed Little Terns – Juvenile ringed in Co. Wicklow and resighted at the Hilbre Island Bird Obs. (Left) and an Adult with yellow ring (right) captured on the nest in Winterton, south east England as part of the Life+ project.

7.3 Licensed photographersThere were several photographers on the license this season, but we only had one visit from a photographer named Michael Stecuik and several visits from the artist Judith Samuel. Next season a permanent hide has been proposed that will be positioned in one of the pens to provide a permanent point of contact for any visiting photographers and also to make visual observations and data collection.

8.0 Recommendations for 2015 An appropriate copy of the license agreement on site to produce for difficult

birdwatchers/photographers. 24 hour warden presence at the site. Streamline data collection, refine the daily shift report worksheet to incorporate

more of the LIFE+ data Include more detailed predator reports. Improved collection method of nest data, specifically the dates of nest fates, possibly

a barcoding system for individual nests. And more nest markers made available towards the start of the season.

New hut. Provision of a warden handbook. Attach fluttering material atop the posts as an extra method of predator deterrent. Laminated contact sheet at the hut for all key contact numbers for emergencies. Volunteers issued with I.D. badges on site

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Encourage volunteers to ‘meet and greet’ at viewing platform. New signs needed to replace outdated and older stock, maybe include signs to

illustrate the impact that disturbance causes on the colony.

9.0 AcknowledgementsThis year’s wardens would like to thank everyone who was involved in helping at Gronant this year. First and foremost, thanks must go to all the volunteers. Their time and effort is invaluable to the sustainability of the colony, and their company was frequently a boost to the wardens’ morale. We would like to thank to Andy, Adrian, Jim and Garry (Denbighshire Countryside Service) for their support and advice. Also thanks to the DCS staff for covering Mondays and Fridays. Thanks to Bourne Leisure for their continued backing of the work and Josh Evans (Coastal Ranger) for his generous assistance. Once again thanks to David Norman for returning for another year to ring the Little Tern Chicks. Finally, thanks to Geoff Robinson, Julian Hughes and John Langley (all RSPB) for their valuable input.

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10.0 Appendices

10.1 Systematic species List 2014

FAUNABirds:

Little tern Sternula albifrons

Cormorant Phalacrocorax carbo

Oystercatcher Haematopus ostralegus

Starling Sturnus vulgaris

Sedge warbler Acrocephalus schoenobaenus

Skylark Alauda arvensis

Sandwich tern Sterna sandvicensis

Shelduck Tadorna tadorna

Dunlin Calidris alpina

Ringed plover Charadrius dubius

Herring gull Larus argentatus

Lesser Black-backed gull Larus fuscus

Great Black-backed gull Larus marinus

Common gull Larus canus

Black headed gull Chroicocephalus ridibundus

Carrion crow Corvus corone

Jackdaw Corvus monedula

Magpie Pica pica

Raven Corvus corax

Grey heron Ardea cinerea

Woodpigeon Columba palumbus

Stonechat Saxicola torquata

Whinchat Saxicola rubetra

Wheatear Oenanthe oenanthe

Reed bunting Emberiza schoeniclus

Whimbrel Numenius phaeopus

Canada goose Branta canadensis

Snipe Gallinago gallinago

Merlin Motacilla cinerea

Linnet Carduelis cannabina

Mallard Anas platyrhynchos

Swallow Hirundo rustica

Swift Apus apus

House martin Delichon urbica

Curlew Numenius arquata

Kestrel Falco tinnunculus

Meadow pipit Anthus pratensis

Greenshank Tringa nebularia

Mute swan Cygnus olor

Moorhen Gallinula chloropus

Coot Fulica atra

Grasshopper warbler Locustella naevia

Blackbird Turdus merula

Pied wagtail Motacilla alba

Little egret Egretta garzetta

Reed warbler Acrocephalus scirpaceus

Buzzard Buteo buteo

Black-headed gull Chroicocephalus ridibundus

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Common scoter Melanitta nigra

Lapwing Vanellus vanellus

Red-breasted merganser Mergus serrator

Sparrowhawk Accipiter nisus

Greenfinch Carduelis chloris

Sand martin Riparia riparia

Corn bunting Emberiza calandra

Yellow wagtail Motacilla flava

Grey wagtail Motacilla cinerea

Eiderduck Somateria mollissima

Red kite Milvus milvus

Peregrine falcon Falco peregrinus

Arctic skua Stercorarius parasiticus

Linnet Carduelis cannabina

Great tit Parus major

Short eared owl Asio flammeus

Mistle thrush Turdus viscivorus

Blue tit Cyanistes caeruleus

Sanderling Calidris alba

Long tailed tit Aegithalos caudatus

Redshank Tringa totanus

Scaup Aythya marila

Mammals

Brown Hare Lepus europaeus

Rabbit Oryctolagus cuniculus

Water Vole Arvicola amphibius

Grey Seal Halichoerus grypus

Fox Vulpes vulpes

Hedgehog Erinaceus europaeus

Wood mouse Apodemus sylvaticus

Otter Lutra lutra

Stoat Mustela erminea

Pygmy Shrew Sorex minutus

Common Shrew Sorex araneus

Brown Rat Rattus norvegicus

Reptiles/amphibians

Sand Lizard Lacerta agilis

Common Lizard Zootoca vivipara

Common Toad Bufo bufo

Common Frog Rana temporaria

Natterjack Toad Epidalea calamita

Palmate Newt Lissotriton helveticus

Invertebrates: Arachnids/opiliones

Woodlouse spider Dysdera crocata

Common orb weaver Metellina segmentata

Walnut orb weaver Nuctenea umbratica

Four-spot orb weaver Araneus quadratus

Spotted wolf spider Pardosa amentata

Garden spider Araneus diadematus

Mother care spider Theridion sisyphium

Sheet-webbed spider Neriene clathrata

Green Orb Weaver Araniella cucurbitina

Comb footed spider Enoplognatha ovata

Nursery web spider Pisaura mirabilis

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Harvestmen sp. Leiobunum rotundum

Harvestmen sp. Phalangium opilio

Harvestmen sp. Opilio parietinus

Harvestmen sp. Opilio saxatilis

Invertebrates; Butterfly’s

Small White Pieris rapae

Peacock butterfly Inachis io

Red admiral Vanessa atalanta

Small heath butterfly Coenonympha pamphilus

Gatekeeper butterfly Pyronia tithonus

Small copper Lycaena phlaeas

Painted Lady butterfly Vanessa cardui

Meadow Brown Maniola jurtina

Holly Blue Celastrina argiolus

Small tortoiseshell Aglais urticae

Comma butterfly Polygonia c-album

Dingy Skipper Erynnis tages

Brown Argus Aricia agestis

Orange tip Anthocharis cardamines

Invertebrates; Moths

Drinker Moth Philudoria potatoria

Magpie moth Abraxas grossulariata

White plume moth Pterophorus pentadactyla

Ruby Tiger moth Phragmatobia fuliginosa

Buff Ermine moth Spilarctia luteum

Forrester moth Adscita statices

Plume moth Stenoptilia pterodactyla

Yellow shell moth Camptogramma bilineata

Six spot burnet moth Zygaena filipendulae

Cinnabar moth Tyria jacobaeae

Invertebrates; beetles

Cardinal beetle Pyrochora serraticornis

Soldier beetle Rhagonycha fulva

Violet beetle Carabus violaceus

Ground beetle sp. Pterostichus madidus

Seven spot ladybird Coccinella septempunctata

Invertebrates; other

Black millipede Tachypodoiulus niger

Flat backed millipede Polydesmus sp

Earwig Dermaptera sp.

Emperor dragonfly Anax Imperater

Common darter Sympetrum striolatum

Common Blue damselfly Enallagma cyathigerum

Large red damselfly Pyrrhosoma nymphula

Common green grasshopper Omocestus viridulus

Field grasshopper Chorthippus brunneus

Mottled grasshopper Myrmeleotettix maculatus

Common ground hopper Tetrix undulata

Speckled bush cricket Leptophyes punctatissma

Red tailed bumblebee Bombus lapidarius

Garden snail Helix aspersa

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Brown lipped snail Cepaea nemoralis

White lipped snail Cepaea hortensis

Leopard slug Limax maximus

Netted slug Deroceras reticulatum

FLORAEquisetaceae

Marsh Horsetail (E. palustre)

Polypodiaceae

Intermediate Polypody (Polypodium interjectum)

Fabaceae

Gorse (Ulex Europeans)

Urticaceae

Common Nettle (Urtica dioica)

Small Nettle (U. urens)

Chenopodiaceae

Red Goosefoot (Chenopodium rubrum)

Common Glasswort (Salicornia europaea agg.)

Annual Sea-blite (Suaeda maritima)

Prickly Saltwort (Salsola kali)

Spear-leaved Orache (Atriplex prostrata)

Frosted Orache (A. laciniata)

Sea-purslane (A. portulacoides)

Sea Beet (Beta vulgaris)

Caryophyllaceae

White Campion (Silene latifolia)

Bladder Campion (S. vulgaris)

Common Chickweed (Stellaria media)

Common Mouse-ear (Cerastium fontanum)

Sea Sandwort (Honckenya peploides)

Thyme-leaved Sandwort (Arenaria serpyllifolia)

Greater Sea-spurrey (Spergularia media)

Sand Spurrey (S. rubra)

Annual Knawel (Scleranthus annuus) rare in Wales

Polygonaceae

Knotweed (Polygonum aviculare)

Ray’s Knotgrass (P. oxyspermum)

Russian-vine (Fallopia baldschuanica)

Broad-leaved Dock (Rumex obtusifolius)

Curled Dock (R. crispus)

Common Sorrel (R. acetosa)

Plumbaginaceae

Common Sea-lavender (Limonium vulgare)

Thrift (Armeria maritima)

Malvaceae

Common Mallow (Malva sylvestris)

Salicaceae

Grey Willow (Salix cinerea agg.)

Brassicaceae

Sea Radish (R. raphanistrum ssp maritima)

Sea Rocket (Cakile maritima)

Hairy Bitter-cress (C. hirsuta)

Common Scurvygrass (Cochlearia offcinalis agg.)

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Primulaceae

Scarlet Pimpernel (Anagallis arvensis)

Crassulaceae

Biting Stonecrop (Sedum acre)

Rosaceae

Crab Apple (Malus sylvestris)

Hawthorn (Crataegus monogyna)

Burnet Rose (Rosa spinosissima)

Dog-rose (R. canina)

Japanese Rose (R. rugosa)

Bramble (Rubus fruticosus agg.)

Silverweed (Potentilla anserina)

Meadowsweet (Filipendula ulmaria)

Fabaceae

Common Restharrow (Ononis repens)

Red Clover (Trifolium pratense)

White Clover (T. repens)

Hare’s-foot Clover (T. arvense)

Common Vetch (Vicia sativa)

Tufted Vetch (V. cracca)

Meadow Vetchling (Lathyrus pratensis)

Black Medick (Medicago lupulina)

Common Bird’s-foot-trefoil (Lotus corniculatus)

Kidney Vetch (Anthyllis vulneraria)

Elaeaganaceae

Sea-buckthorn (Hippophae rhamnoides)

Onagraceae

Broad-leaved Willowherb (Epilobium montanum)

Great Willowherb (E. hirsutum)

Rosebay Willowherb (Chamerion angustifolium)

Evening Primrose (Oenothera agg.)

Aquifoliaceae

Holly (Ilex aquifolium)

Euphorbiaceae

Sea Spurge (Euphorbia paralias)

Portland Spurge (E. portlandica)

Aceraceae

Sycamore (Acer pseudoplatanus)

Geraniaceae

Herb-Robert (Geranium robertianum)

Dove’s-foot Crane’s-bill (G. molle)

Apiaceae

Cow Parsley (Anthriscus sylestris)

Hogweed (Heracleum sphondylium)

Alexanders (Smyrnium olusatrum)

Sea-holly (Eryngium maritimum)

Wild Carrot (Daucus carota ssp carota)

Gentianaceae

Common Centuary (Centaurium erythraea)

Seaside Centuary (C. littorale)

Convolvulaceae

Hedge Bindweed (Calystegia sepium)

Boraginaceae

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Hound’s-tongue (Cynoglossum officinale)

Alkanet (Anchusa officinalis)

Lamiaceae

Bugle (Ajuga Reptans)

Water Mint (Mentha aquatica)

Red Dead-nettle (Lamium purpureum)

Hedge Woundwort (Stachys sylvatica)

Hippuridaceae

Mare’s-tail (Hippuris vulgaris)

Plantaginaceae

Ribwort Plantain (Plantago lanceolata)

Greater Plantain (P. major)

Sea Plantain (P. maritima)

Buck’s-horn Plantain (P. coronopus)

Oleaceae

Liliac (Syringa vulgaris)

Scrophulariaceae

Foxglove (Digitalis purpurea)

Common Field Speedwell (Veronica persica)

Eyebright (Euphrasia sp.)

Yellow-rattle (Rhinanthus minor)

Rubiaceae

Cleavers (Galium aparine)

Lady’s Bedstraw (G. verum)

Caprifoliaceae

Honeysuckle (Lonicera periclymenum)

Valerianaceae

Common Valerian (Valeriana officinalis)

Asteraceae

Common Ragwort (Senecio jacobaea)

Welsh Groundsel (S. cambrensis)

Groundsel (S. vulgaris)

Sea Aster (Aster tripolium)

Yarrow (Achillea millefolium)

Hemp-agrimony (Eupatorium cannabinum)

Sea Mayweed (Tripleurospermum maritimum)

Pineappleweed (Matricaria discoidea)

Chamomile (Chamaemelum nobile)

Mugwort (Artemisia vulgaris)

Spear Thistle (Cirsium vulgare)

Creeping Thistle (C. arvense)

Common Knapweed (Centaurea nigra)

Dandelion (Taraxacum agg.)

Goat’s-beard (Tragopogon pratensis agg.)

Great Lettuce (Lactuca virosa)

Nipplewort (Lapsana communis)

Clematis

Clematis Tangutica, Bill Mackenzie

Juncaginaceae

Sea Arrowgrass (Triglochin maritimum)

Liliaceae

Yellow Iris (Iris pseudacorus)

Asparagus (Asparagus officinalis)

Orchidaceae

Pyramidal Orchid (Anacamptis pyramidalis)

Common Spotted-orchid (Dactylorhiza fuchsii)

Bee Orchid (Ophrys apifera)

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executive summary - north wales little tern group ... · web view1 handheld infrared thermometer...

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