Friday, 31 August 2012

Diverse marine habitats

After a busy weekend of multibeam, a low pressure weather system moved in and
the Pole Star was forced to head back to Oban to shelter. This gave us time to
back-up and examine the data we had collected during the previous week.

Based on multibeam data that Gill and Kirsten (BGS) processed on board, we
were able to select locations for sampling. Groundtruthing is an important part of
the survey as it allows us to assign particular habitats to corresponding areas of
multibeam. The two pieces of equipment we are utilising for this purpose are a
drop-camera and Day grab. The drop camera allows us to take videos and
high-resolution stills of organisms living on the reef or projecting from the
sediment, whilst grab samples of sediment allow us to extract organisms from
within. Cefas are providing technical support and expertise in the form of Simon
and Jo to assist with the groundtruthing.

Stanton Banks SCI is proposed for designation because of its Annex I rocky and
stony reef habitat. Through use of the drop camera, we now have information on
the types of species that live on and around the reef. From images collected so
far, we have seen various types of crab, starfish, featherstar, sea urchin and sponge.

Brittlestars (Ophiocomina nigra)

Edible crab (Cancer pagurus)

Featherstars (Leptometra celtica) and squat lobster (Munida rugosa)

We have also found muddy sediments around the reef features. Though there are
 fewer conspicuous species on the surface compared to the rocky areas, we have
seen a number of sea pens and nephrops.

Sea pens (Funiculina quadrangularis) and langoustine (Nephrops norvegicus)
We are currently heading for a crew change before transiting back out to Stanton
Banks to try and finish the survey in a good weather window between gales.