IOS 2007.Pub
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2 Tean Sound has a large variety of anemones in the sandy channel and 1 Hard Lewis Rocks/Juno wreck was the first dive. Below a kelp 12 Darrity’s Hole has a very silty boulder field with many sponges, amongst the eelgrass Zostera marina which park, vertical walls covered in jewel anemones Corynactis viridis, cnidarians and ascidians. The sponge forms thick, healthy beds. The red speckled red fingers Alcyonium Axinella damicornis (right) and the pimplet anemone Anthopleura ballii, the daisy glomeratum (right) and white volcano sponge Haliclona viscosa anemone Cereus pedunculatus and the fingers A. digitatum, pink sea were both abundant. Jewel snakelocks anemone Anemonia viridis were fans Eunicella verrucosa, anemones were common, ginger tiny recorded as common together with an unusual various hydroids and sponges anemones frequent whilst pink sea colour form of the gem anemone Aulactinia dropped from 13m to boulders fans, the pink sea squirt Sydnium verrucosa (right). The bryozoan Turbicellepora and mixed ground at 25m. elegans, lightbulb sea squirts magnicostata, was an unusual find here (see Ballan wrasse and goldsinny Clavelina lepadiformis and a pipefish back page). were recorded as frequent. Sygnathus acus were all recorded. 3 West Hoe Point is an area of vertical fissured rock faces and Previous surveys have covered a total of 27 sites. Weather and poor underwater 11 North Chapel Rock is a rocky pinnacle extending from the kelp enormous boulders. The very rare red blenny Parablennius zone in 20m, steeply down with narrow ledges to boulders at 27m. ruber was recorded in one of the fissures, usually a more visibility (macro photography only) were a limiting factor for dive sites but 4 new sites The sponges Adreus fasicularis, Axinella damicornis, Stelligera southerly species. Common on the vertical faces were jewel were surveyed together with 8 previously rigida, sea orange Suberites ficus, prawn cracker sponge, anemones, Devon cup coral Caryophyllia smithii, white dead surveyed sites. 6 2 11 5 hedgehog sponge and yellow staghorn sponge were among 14 men’s fingers, spiral bryozoans Bugula sp., boring sponge 1 species of sponge recorded, predominantly on the ledges. Sixteen Cliona celata and crater bryozoa species included Crisia eburnea, Bicellaria ciliata, Cellaria sponge Hemimycale spp. and potato crisp bryozoan as columella. The yellow common and 3 species of spiral staghorn sponge bryozoan as occasional. Nationally Axinella dissimilis (left) rare sea fan anemones Amphianthus was common on the silt 10 dohrnii were recorded on one sea covered ledges and 9 fan together with the sea fan horizontal boulder tops nudibranch Tritonia nilsodhneri (right, together with the ginger with eggs). A total of 75 species were tiny anemone recorded at this new, very rich site. Isozoanthus sulcatus. 12 10 Menawethen Despite the pleasant distraction of the playful 4 Wingletang Ledges was a new and very interesting survey seals 30 species were recorded at this annually visited site site chosen to confirm a record of the rare sunset cup coral including the scarce scarlet and gold cup coral Balanophyllia regia. Leptopsammia pruvoti (picture front cover). A new colony was 8 9 Ridge High Corner was a new survey site. From 10m a flat confirmed under an overhang together with the southern cup topped reef with abundant golden kelp fell in a series of steep faces coral Caryophyllia inornata, Devon cup coral and nearby red and and silty ledges to a boulder slope at 32m. A total of 53 recorded white fingers, plumose anemones Metridium senile and white species included Devon and southern cup corals, jewel and striped anemones Actinothoe sphyrodeta. Nine species of algae, plumose anemones, whilst dead men’s fingers dominated the steep 7 of hydroid and 4 of nudibranch were also recorded. areas. On the ledges 9 species of hydroid including both oaten pipe 5 Flat Ledges is a steep 3 hydroids Tubularia indivisa and T. larynx, 5 species of bryozoa and 10 sponge species including Leuconia johnstoni were recorded . sided, flat topped reef with 7 4 wide vertical clefts and 8 The Cita is a relatively recent wreck gullies and a series of silt but well colonised and 57 species covered flat ledges in steps were recorded. On the deck the south from 20m downwards. 7 Plympton/Hathor The lower lying Plympton west species of golden kelp Laminaria Thirteen species of sponge wreckage had abundant healthy pink sea fans ochroleuca, pink sea fans and the were recorded including the Eunicella verrucosa, including white ones. blue sponge Terpios fugax were tiny stalked sponge Sponge species included the slime sponge found. Seven other sponge species Guancha lacunosa, prawn Desmacidon fruticosum were identified together with several cracker sponge Axinella (left). Large specimens unidentified encrusting ones. A white infundibuliformis (right), chimney sponge Polymastia penicillus of the football sea squirt cluster anemone Parazoanthus axinellae (or anguicomis?) was and hedgehog sponge P. boletiformis. Diazona violacea (right) recorded on the more sheltered side of the wreck. 6 Peter’s Rock is a similar site close by. A rich species list were recorded on the Newfoundland Point is a high activity rocky reef with vertical walls, provided 67 species in total including 9 algae species, 14 boiler of the Hathor. ledges and many large boulders forming surge gullies. Elegant sponge, 6 hydroid, 6 nudibranch (Coryphella browni photo on On the adjacent reef 9 bryozoa species were noted anemones Sagartia elegans (above) were abundant with Devon front page) and 10 bryozoa species. The sponge Adreus together with an orange coloured false cowrie Simnia cup coral and jewel anemones being recorded as super-abundant. fascicularis was recorded here (photo back page). patula on dead men’s fingers. The table to the right shows numbers of Phylum Common name Number Common species species recorded in each group and of species some of the most widely distributed species. The table and this report have Porifera Sponges 30 Boring sponge Cliona celata Yellow staghorn Axinella dissimilis been prepared from a total of 5 Observer sponge forms and 12 Surveyor forms. Sponges were recorded at all sites Cnidaria Anemones, corals, 38 Sea beard Nemertesia spp hydroids Dead men’s fingers Alcyonium digitatum except Tean Sound. The rare Adreus Red fingers Alcyonium glomeratum fascicularis (below) was recorded at Plumose anemone Metridium senile Peter’s Rock & North Chapel Rock, the Elegant anemone Sagartia elegans slime sponge Desmacidin fruticosum on Jewel anemone Corynactis viridis Devonshire cup coral Caryophyllia smithii the Plympton wreck. Pink sea fan Eunicella verrucosa Annelida Segmented worms 4 Crustacea Crabs, lobsters, 5 Edible crab Cancer pagurus barnacles Velvet swimming crab Necora puber Mollusca Shells, sea slugs 14 Nudibranch Coryphella browni Nudibranch Polycera faeroensis Bryozoa Sea mats 41 Potato crisp bryozoan Pentapora foliacea Sea mat Membranipora membrana- cea Spiral bryozoan Bugula spp. Echinodermata Starfish, 11 Common urchin Echinus esculentus Anemones, Corals and Hydroids were sea urchins, Cotton spinner Holothuria forskali commonly recorded at all sites. Pink sea sea cucumbers Spiny starfish Marthasterias glacialis fans Eunicella verrucosa were found at 8 whilst the rare sea fan anemone Amphi- Tunicata Sea squirts 11 Lightbulb sea squirt Clavelina lepadiformis anthus dohrnii was found at North Pisces Fish 15 Ballan wrasse Labrus bergylta Chapel Rock only. Four varieties of cup Cuckoo wrasse Labrus mixtus Isles of Scilly Survey coral included scarlet and gold Balano- Goldsinny Ctenolabrus rupestris phyllia regia at Menawethen and nation- Mammalia Mammals 1 Grey seal Halichoerus grypus May 2007 ally rare sunset Leptopsammia pruvoti at Algae Seaweeds 18 Cuvie Laminaria hyperborea Wingletang Ledges. Ginger tiny anem- Sea beech Delessaria sanguinea Summary Report ones Isozoanthus sulcatus occurred at 5 Pink encrusting sites and Tubularia hydroids (below) at 8 Angiospermae Eelgrass 1 Eelgrass Zostera marina sites. Sunset cup coral Bryozoans were of special interest to two divers from Aberystwyth University. Samples were collected for identification and microscopic examination and the local bryozoan fauna proved especially rich, two species being of particular interest. Both are normally found in the Mediterranean, with their only recorded UK location as the Isles of Scilly. Turbicellepora magnicostata (electron microscope image right) forms bright orange lumps and was abundant on algae in Tean Crabs, Lobsters and Molluscs were sound. Schizoporella dunkeri ( below), again bright orange, encrusted small rocks at Spiral bryozoan recorded in small numbers at most sites. Hard Lewis Rocks and North Chapel Rocks. It will be interesting to see if either Nudibranchs were frequently recorded species are present on other south-western sites. but only one sea fan nudibranch Tritonia Jewel anemones with nilsodhneri was seen, at North Chapel Fish included ballan, cuckoo and goldsinny spiky lace sponge Rock. wrasse at most sites, the rare and usually Starfish, Sea urchins and Sea more southerly species of red blenny cucumbers included cotton spinners Parablennius ruber at West Hoe Point and a Holothuria forskali, urchins Echinus more northerly species, the lumpsucker esculentus and spiny starfish Cyclopterus lumpus at Wingletang Ledges. Marthasterias glacialis at most sites and Seaweeds were recorded at all sites. The featherstars Antedon bifida at 2 sites. south-western kelp species Laminaria ochro-