Hi Bryony and all,
I'm sure Richard has got some private replies, but they aren't much good for the rest of us so. From the other side of the world I will make a couple of comments to stimulate debate but I haven't got an answer.
They do look rather like stranded salps, but I don't think they are. There's no coloured internal organs to be seen, and they do appear to be attached to burrows, and there is a definite burrow opening which more suggests a mobile surface-feeding species, rather than a deposit feeder such as Arenicola. Also UK Arenicola marina breeds in autumn (October onwards) and doesn't produce egg cocoons AFAIK (A. cristata & A. brasiliensis do). North Sea Scoloplos armiger produce egg cocoons but reproduce in February (but March on Guernsey - http://www.sustainableguernsey.info/blog/2011/03/its-worm-spawning-time-on-guernseys-beaches/ ).
Maybe a bit of work with a spade might have solved this one on the spot? Also it would be good to see the contents (eggs/embryos if present) up close.
>>> On 4/07/2011 at 9:09 p.m., Bryony Pearce <bryony from seasurvey.co.uk> wrote:
> Hi Richard,
>> I may be wrong but these look like salps to me.
>> Best Regards
>> Research Director
> Marine Ecological Surveys Limited
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