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MARINE RECORDER REPORT 2016 AND 2017 GEN BROAD From sponges to seals I am grateful to the Seasearch East team (led by Dawn Watson and Rob Spray) for submitting their 2016 marine records for a wide range of marine groups including seaweeds, tunicates, polychaete worms, sponges, hydrozoans, crustaceans, molluscs and bryozoans from sites in Aldeburgh, Orford Ness, Levington Marina, Felixstowe and Lowestoft. In addition, SNS member Jerry Bowdrey has made a significant contribution to marine records from strandline walks at Southwold, Sizewell and Thorpeness. These include records of sharks, jellyfish and squid, which shows just what interesting and unexpected finds can be made on our beaches!

The following gives an indication only of the scope of the records submitted by Seasearch East. Common species at Orford Ness pontoon included Oaten pipes hydroid Tubularia indivisa, the sea anemone Diadumene cincta, Common mussel Mytilus edulis, Orange-tip nudibranch Cuthona gymnota and the Peacock worm Sabella pavonina. Frequent and abundant species at Levington Marina included Orange-tipped sea squirt Corella eumyota, the solitary sea squirt Ascidiella aspersa, Star Ascidian Botryllus schlosseri and two non-native seaweeds - Wakame or Japanese kelp Undaria pinnatifida and Wireweed Sargassum muticum, originally from Japan and China.

Crustaceans recorded from Felixstowe included the Hermit crab Pagurus bernhardus, Shore crab Carcinus maenas and Velvet swimming crab Necora puber.

Sea grapes (Molgula sp.), a common genus of sea squirts, were recorded from four of the Seasearch sites - Lowestoft, Levington Marina, Felixstowe and Aldeburgh.

Three Northern or Veined Squid (Loligo forbesi) were washed up on Thorpeness beach in August 2017 (Plate 17) and identified by Dr Vladimir Laptikhovsky of the Centre for the Environment, Fisheries and Aquaculture Science (Cefas). Dr Laptikhovsky believes these were probably juveniles, descendants of the winter spawning off Scotland, which then forage across the North Sea. Although juveniles do not have the distinctive ventral “stripes” of the adults, the species can be identified by the tentacular clubs which have suckers all of the same size. The central two rows of suckers on the tentacular club are much larger than the outer two rows on the similar European squid Loligo vulgaris.

Jerry Bowdrey, who reported finding these individuals, also found a squid ‘pen’, probably from the same species, on the strandline between Shingle Street and Bawdsey in September 2017.

The remains of two sharks were found on Southwold beach in January 2017 (also

by Jerry Bowdrey). Scavengers had eaten parts of the animals and most of the key features were missing, but Dr Jim Ellis from Cefas suggested that the remains were probably those of the Spiny Dogfish or Spurdog Squalus acanthias (Plate 12).

This is one of the most common small sharks in the East of England, especially in the winter months, along with the Starry Smooth-hound and Tope. The approximate position of the pectoral and pelvic fins, the shape of the snout, the appearance of the eye and spiracles all point to these remains being those of Spurdog.

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The Barrel jellyfish Rhizostoma pulmo was recorded for the first time in Suffolk on 12th January 2016 when a fisherman pulled an individual out with his nets two miles east of Aldeburgh. Subsequently, on 29th January 2016, three or four badly damaged individuals were found by Jerry Bowdrey on Sizewell Beach, although these were juveniles only 10 cm across (Plate 18). This species is usually found in the south and west of the UK and the nearest records prior to these sightings were from Scarborough to the north and Margate and Folkestone in Kent to the south. This immense jellyfish is the largest found in British waters, which is why it is also known as the dustbin lid jellyfish. It can grow to an enormous size, with a thick dome shaped bell up to 90 cm in diameter and weighing up to 35 kilos, although it is more commonly seen at half that size and weight. The arms are covered in frilly tissue where they meet the body, hence the alternative name ‘frilly mouthed jellyfish’. The frills are actually small dense tentacles which are used to catch prey and pass them into the hundreds of small mouths which they surround.

The species can be identified from the large size, four pairs of very large oral arms on the under-surface and the lack of marginal tentacles. It is a favourite food of the leatherback turtle and is found in the northeast Atlantic, the Adriatic and Mediterranean Seas, and the southern Atlantic Ocean. They usually drift in deep ocean waters, but sometimes come inshore to feed on plankton blooms.

Whilst walking on Sizewell beach in July 2016, Jerry also found several individuals of the Ribbed Jellyfish Aequorea forskalea and one Compass jellyfish Chrysaora hyascella.

Paul Wilkinson spotted some interesting tracks on Eastern Bavents beach in August 2017 (Plate 11), which turned out to be those of a Common seal Phoca vitulina, which he successfully photographed on a later occasion (Plate X inset). The Common seal is smaller than the Grey seal and can be distinguished by its blunter, more dog-shaped profile. Both species are protected under the Conservation of Seals Act 1970 and listed as Priority species under the Section 41 (S41) of the 2006 Natural Environment and Rural Communities (NERC) Act. Seasearch East is part of the Marine Conservation Society’s Seasearch program which aims to establish an ongoing survey of the UK’s marine wildlife to identify important habitats and vulnerable species. The surveys also help to monitor change and identify the effects of human and natural influences. Thanks to its silty substrate and low visibility waters, the East coast, and Suffolk in particular, is the least surveyed of the UK’s marine environments. Many of Seasearch’s records are ‘firsts’ for Suffolk, an indication of how little marine survey work has previously been undertaken.

References Sabatini, M. (2004). Rhizostoma pulmo Dustbin-lid jellyfish. In Tyler-Walters H. and Hiscock K. (eds) Marine Life Information Network: Biology and Sensitivity Key Information Reviews, [on-line]. Plymouth: Marine Biological Association of the United Kingdom. Available from: http://www.marlin.ac.uk/species/detail/2027 Laptikvhosky, V. & Ourens, R. (2017). Identification guide for shelf cephalopods in the UK waters (North Sea, the English Channel, Celtic and Irish seas). Centre for the Environment, Fisheries and Aquaculture Science UK. ver. 2 15.9.2017.

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Plate 11: Tracks on the beach at Easton Bavents, August 2017 (p. 104). Inset shows the Common Seal Phoca vitulina (photographed later) that probably made them.

Plate 12: Remains of Spiny Dogfish or Spurdog Squalus acanthias found on Southwold beach on 11 January 2017 (p. 103)

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Plate 17: Northern or Veined squid Loligo forbesi found on Thorpeness beach on 27 August (p. 103).

Plate 18: Juvenile barrel Jellyfish Rhizostoma pulmo found on Sizewell Beach January 2016 (p. 104).

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