On Web version, right click on the screen and choose “Edit
slides” to view supporting text
Revealing the reef: marine life settling on ex-HMS
Scylla Keith Hiscock
Last updated: 9th March 2009
Including information from the Settling on Scylla project
Get this presentation: www.marlin.ac.uk/learningzone/scylla
The presentation:
• How Scylla was before sinking on 27 March 2004.
• What could we expect: experience from other artificial reefs.
• The ‘time-line’ of marine life settlement.
• How you can help maintain records from Scylla – and get involved in reporting marine life observations.(All with thanks to: Plymouth Sound BS-AC; MCS local group especially Amy Bugg; Sally Sharrock; Peter Messenger; University of Plymouth Diving Centre, Unicomarine for identification of samples, and many others for the diving, the marine life records and the use of images.
And, of course, the National Marine Aquarium for putting Scylla on the seabed - right-way-up.)
19 November 2003. Devonport
Inspection of existing fouling
Oysters, sponges, barnacles etc. on one of the propellers
27 March 2004
www.national-aquarium.co.uk
Other UK artificial reefs: Poole Bay(See: Jensen, A.C. & Collins, K.J., 1995, The Poole Bay artificial reef project. Biologia Marina Mediterranea 2, 111-122.)
Images courtesy of Antony Jensen
Other UK artificial reefs: Poole Bay(From: Jensen, A.C. & Collins, K.J., 1995, The Poole Bay artificial reef project. Biologia Marina Mediterranea 2, 111-122.)
Other UK artificial reefs: MV Robert at Lundy (sunk, January 1975, survey 1980)
Starboard (horizontal) side: 192 taxa (species or species groups) sampled from 1.4 sq. m; 39 taxa by observation; 29 taxa in c. 1 sq. m of close-up photographs.
Other UK artificial reefs: local wrecks
Persier
Scylla. In the first year:1. a small numbers of potentially resident fish (poor cod) were attracted after about 10 days;2. colonisation by barnacles, tube worms, Obelia hydroids and microbial slime occurred within about four weeks;
4. barnacles, tube worms and Obelia hydroids became common at about 6-7 weeks and are joined by Tubularia hydroids and, on shallow parts, brown filamentous algae;5. by ten weeks after placement, the variety of organisms was significant and kelp, solitary sea squirts, anemones etc. had settled.
3. ‘wandering’ species find the reef (spiny starfish, spiny spider crabs, long-spined sea scorpion etc.);
Poor cod
Colonisation by microbial slime, barnacles, tube worms and Obelia hydroids had occurred within about four weeks
23 April 2004
Barnacles, Balanus crenatus Tube worms, Pomatoceros triqueter
23 April 2004
9 June 2004
Brown filamentous algae
25 June 2004
Spiny starfish, Marthasterias glacialis
30 July 2004
Keeled tube worms, Pomatoceros triqueter, saddle oysters, Heteranomia squamula etc.
Scylla. In the first year (continued):
8. by 30 weeks, juvenile queen scallops abundant over and in the vessel. Green urchins and common starfish now abundant and largish.
6. by 18 weeks, a wide variety of species including mass settlement of juvenile queen scallops, many ‘decorata’ anemones, extensive growths of Tubularia hydroids, variety of algae etc. Mussels settling. Tube worms and solitary sea squirts cover some surfaces. Algae abundant on upper surfaces;
7. by 24 weeks, green urchins and common starfish have settled in large numbers;
30 July 2004
Queen scallops settle
18 February 2005
Queen scallop, Aequipecten opercularis inside the vessel
30 July 2004
Decorata anemone, Sagartia troglodytes decorata
9 June 2004
Tubularia hydroid
9 June 2004
Encrusting sea mat, ?Electra pilosa
30 July 2004
Solitary sea squirts, Ciona intestinalis
30 July 2004
Brown alga, Cutleria multifida
30 July 2004
Filamentous red algae
30 July 2004
Facelina bostoniensis and eggs
30 July 2004
25 September 2004
By end of the summer: dense colonisation – but the urchins and starfish have settled
10 November 2004
Mussels, Mytilus edulis Image: Sally Sharrock
Scylla. In the first year (continued)
9. green sea urchins and common starfish together with normal seasonal decline have removed algal growth and much barnacle and tube worm cover;
By midwinter (40-48 weeks):
10. common starfish have removed mussels, barnacles and, no doubt, other species;
11. the reef looks ‘bare’;
12. plumose anemones are reproducing (by basal laceration) and are becoming visually dominant near the bow;
14. corkwing wrasse observed ‘holding territory’.
13. calcareous sponges have settled;
18 February 2005
Green sea urchin Psammechinus miliaris
18 February 2005
Common starfish, Asterias rubens
18 February 2005
Cleaned by urchins & starfish
18 February 2005
Plumose anemone, Metridium senile
18 February 2005
Calcareous sponges, Leucosolenia botryoides & Sycon ciliatum
18 February 2005
Colonisation on below-waterline black paint. Effective antifouling paint
30 January 2005
Corkwing wrasse on the starboard walkway
Scylla. In the first year (continued)
15. much of vessel still very bare (grazed);
By the end of and after one year (50-55 weeks):
16. but, algae have returned;
17. common starfish declining and green sea urchins possibly less abundant.
19 March 2005
The bow: still very grazed
By the end of one year, we had:
1. recorded (through the year and from various sources) a total of 53 species on or in Scylla (excluding surrounding seabed species);
2. been able to track sequence of species colonisation (and loss) through the year;
3. had a few surprises (unexpected settlements).
In the second year (2005): losses and gains
1. Grazing much less (sea urchins decline dramatically, starfish less abundant).
2. Some significant new species settle.
3. Plumose anemones become visually dominant in many areas.
4. In the reduced grazing regime, tubeworms, barnacles and foliose algae thrive.
Urchin midden
15 July 2005
Algae have colonised the foredeck – but a small variety of filamentous species
7 September 2005
Jewel anemones
7 September 2005
Jewel anemones
20 August 2006
Dead mens fingers
15 July 200515 July 2005
20 August 2006
Leathery sea squirts – present from about October 2004, common by 2006
During the winter 2005-6 and into 2006, visually dominant species expand and the reef communities begin to stabilize.
1. Plumose anemones are abundant in some areas
2. Dead man’s fingers are common and grow to full size
3. Leathery sea squirts begin to be conspicuous
But still room for more – especially inside
Plumose anemones on prop shaft
28 January 2006
Still plenty of room inside
28 January 2006
Ross, Pentapora fascialis
25 March 2006
Omalosecosa ramulosa: a branching sea mat (bryozoan)
20 August 2006
Sea beard, Nemertesia antennina, first seen winter 05/06
30 August 2006
Dead mens fingers now common and nearly full grown (and more have settled)
18 August 2006
Top of the reef colonised by ‘expected’ variety of seaweeds including kelp
18 August 2006
Foredeck colonised by ‘expected’ variety of foliose seaweeds
20 August 2006
Lots more fish by end of summer 2006 – scad off the bow
20 August 2006
The urchins are back! (but not so many) – and a 2006 settlement of dead mens fingers
20 August 2006
The scallops are back! (but not so many)
20 August 2006
Records of dahlia anemones confirmed (Image: Sally Sharrock)
28 August 2006
Sagartia elegans rosea
7 October 2006
Many parts of the outside of the reefs are ‘solid’ with colonisation and a wide variety of species
18 August 2006
Some parts of the reefs might even qualify as “pretty”
18 August 2006
But, colonisation of the anti-fouling-painted areas restricted to patches where paint has flaked (under the stern)
18 August 2006
By end of August 2006 (from our ‘Wanted’ list of spring 2005 & before ‘Scylla week’):
White sea fingers Red sea fingers
Ross Edible sea urchin Pink sea fan
Devonshire cup corals
First seen First seen June 2005June 2005
First seen First seen Sept 2005Sept 2005
First seen First seen March 2006March 2006 Still lookingStill looking Still lookingStill looking
126 species recorded from Scylla from observations and photographs
Still lookingStill looking
Sampling the little beasties (worms, crustaceans etc.)
30 August 2006 and during the subsequent Scylla Week
About 84 additional species identified by Unicomarine from samples taken in Scylla Week, bringing the total number of species identified on Scylla to about 220
By the end of 2006, most of the species that were to be visually dominant on the reef had settled.
But those species had to expand in abundance and grow in size before Scylla would qualify as hosting a ‘mature steel wreck community’.
And some ‘expected’ species were still unaccounted for.
27 April 200727 April 2007
Red sea fingers were first seen in April 2007Red sea fingers were first seen in April 2007
17 August 200717 August 2007
Orange pumice bryozoan, Orange pumice bryozoan, Cellepora pumicosaCellepora pumicosa were first observed in late summer were first observed in late summer 2006 and, unexpectedly, became extremely abundant in the next year.2006 and, unexpectedly, became extremely abundant in the next year.
15 June 200715 June 2007
By summer 2007, established species characteristic of wrecks were growing By summer 2007, established species characteristic of wrecks were growing towards full size: dead man’s fingers, ross and orange pumice bryozoans were towards full size: dead man’s fingers, ross and orange pumice bryozoans were abundantabundant
19 September 200819 September 2008
Sea urchins, Sea urchins, Echinus esculentusEchinus esculentus were not reported from the reef until 30 were not reported from the reef until 30 September 2007September 2007
10 December 200810 December 2008
Seafans, Seafans, Eunicella verrucosaEunicella verrucosa, settled in about July 2007 – and some grew rapidly, settled in about July 2007 – and some grew rapidly
19 September 200819 September 2008
Feather stars, Feather stars, Antedon bifidaAntedon bifida only became abundant in 2008 only became abundant in 2008
There are significant seasonal changes on Scylla – winter scene with few algae on There are significant seasonal changes on Scylla – winter scene with few algae on shallow decksshallow decks
10 December 200810 December 2008
10 December 200810 December 2008
Two of the conspicuous characterising animals, species of oaten pipe hydroids, Two of the conspicuous characterising animals, species of oaten pipe hydroids, are devastated by sea slugs in summer and die back in late-winter.are devastated by sea slugs in summer and die back in late-winter.
26 February 200926 February 2009
Spring growth beginning – sea beech Spring growth beginning – sea beech Delesseria sanguineaDelesseria sanguinea
26 February 200926 February 2009
Topknot ‘braving’ the anti-fouling paint under the sternTopknot ‘braving’ the anti-fouling paint under the stern
By end of March 2009 (from our ‘Wanted’ list of spring 2005 & after ‘Scylla week’):
Dead man’s fingers Red sea fingers
Ross Edible sea urchin Pink sea fan
Devonshire cup corals
First seen First seen June 2005June 2005
First seen First seen Sept 2005Sept 2005
First seen First seen March 2006March 2006
First seen First seen Sept 2007Sept 2007
First seen First seen August 2007August 2007
258 species recorded from Scylla from observations, photographs and samples
First seen First seen April 2007April 2007
Some species are expected to increase in abundance over the next few years:
Fish, especially wrasse
Edible sea urchins
Devonshire cup corals
We are still waiting to see some species that occur commonly on steel wrecks in south Devon and Cornwall:
Lobster
Cotton spinner
Yellow boring sponge (massive form)
Sandaled anemone Actinothoë sphyrodeta
Scylla now hosts (March 2009, five years after placement) Scylla now hosts (March 2009, five years after placement)
a mature steel wreck wildlife communitya mature steel wreck wildlife community
Report any unusual or interesting marine Report any unusual or interesting marine life (supported by images where possible):life (supported by images where possible):
Get this presentation:Get this presentation: www.marlin.ac.uk/learningzone/scylla www.marlin.ac.uk/learningzone/scylla
MarLINMarLIN24 hr reporting hotline:24 hr reporting hotline:
01752 25502601752 255026E-mail images to: [email protected] images to: [email protected]
Join-up:Join-up: www.mcsuk.org; www.seasearch.org.uk www.mcsuk.org; www.seasearch.org.uk