Reference
Invertebrate life on the nets
UKDIVING
Tube worm colony
PHOTO : KATHRYN FOWLER
PHOTO : KATHRYN FOWLER
amusement as there were numerous small scallops dispersed over the hull .
Twenty-four distinct species were recorded during this second dive , and this will not have been an exhaustive list .
Dive 3 : 27 June 2021
We returned to Polaris in June 2021 . We found the wreck had rolled further onto its port side , presumably during the storms of the previous winter . However there appeared to be no further degradation of the structure of the boat .
The hull was still devoid of life where the antifoul had been painted , although studies of the ex-HMS Scylla [ Plymouth ’ s purpose
sunk frigate wreck ] reported that this largely held true five years after the sinking of that particular vessel . Fluted sea squirts and hydroids remained the dominant species on the upper section of the hull . Several species of nudibranch and some egg spirals were spotted during this dive .
The peacock worms and dead men ’ s fingers coral on the nets were recorded as more abundant than on the previous dive . Together with the hydroids that were still present they left little of the net now exposed .
There were plumose anemones ( Metridium senile ) on the wreck that we hadn ’ t recorded as present on the previous
Plumose anemones , a recent coloniser
Squid egg bundles
PHOTO : KATHRYN FOWLER dives . This is a species that is abundant on other established wrecks in the area . The large number of fish , particularly bib ( Trisopterus luscus ) and pollack ( Pollachius pollachius ) was also striking .
Project limitations
A number of contributing factors have led to fewer dives taking place on Polaris than originally hoped for . The offshore position means that favourable tides and weather ideally have to coincide with weekends for daytime availability of the dive team . Intermittent COVID restrictions through 2020 and 2021 further limited diving opportunities .
The study of the colonisation of ex-HMS Scylla observed seasonal changes in the species colonising the wreck , particularly in the early years ( Hiscock et al . 2010 ). With our dives so spaced out and at different times in the year we have observed snapshots of colonisation . While there has been apparent change in species present and increase in species diversity , seasonal variations of species present and their relative abundance will have undoubtedly been missed . We also acknowledge that the species recorded on each dive are limited to those we spot and are able to identify . The lists will by no means be exhaustive .
Nearby established wrecks , particularly those constructed of similar materials , give an idea of what species we would expect to see on Polaris given time . Our plan is to continue to dive Polaris and record the condition of the wreck and the species present through Seasearch over the next few years . We enjoyed watching how the site has changed in its first two years and there is an anticipation of what future dives will reveal . �
PHOTO : KATHRYN FOWLER
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Reference
Hiscock , K ., Sharrock , S ., Highfield , J . & Snelling , D . ( 2010 ) Colonization of an artificial reef in south-west England- ex-HMS ‘ Scylla ’. Journal of the Marine Biological Association of the United Kingdom . 90 ( 1 ) January , pp . 69-94