dejayM's picture

Grazing rites

Observed: 19th May 2013 By: dejayM
Biological Recording In ScotlandHighland Biological Recording GroupOrkney Biodiversity Records Centre
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old one

These marks are well up in the tide zone; the animals pretty well housed in deep depressions.
I got the impression that as soon as the water arrived (probably for only two hours) they took off to the restaurants.
Nearest animal, in some cases, was 1.8 metres. Some could be in baking sunshine for over 9 hours.

Species interactions

No interactions present.


JoC's picture


DJ: What do you mean by "Nearest animal, in some cases, was 1.8 metres"?


dejayM's picture

distant diners

Oh..the very nearest Limpet, as seen in the pictures was, in some cases, stationed about 5 feet away. Suggesting that they moved that distance to feed and the same back, to their lairs.
Of course, there were other animals (sorry), perhaps periwinkles and crabs but these marks were left by the grazing Limpets.
The pictures are taken about 4 hours before the next high water and possibly more than 8 hours after the Limpets had their last feed. (if they do so daily or 'tidely').
I'd like to study this cycle a bit more closely. How often they might feed; how they cope with the heat of the day.

dejayM's picture

common limpets - ha!

Ordinarily and not long ago I would have felt comfortable about Common limpet. But they are really quite difficult to tell apart via just shell-views. Personally I would rather see these titled Limpet but with notes suggesting that they might be one of, perhaps, three.
I have been through this several times with an expert, including having empty shells to hand, to the conclusion that it really IS hard to tell them apart unless one can see the animal or at least the underside - which usually means killing it.
That it is common and that other examples can be seen as close lookalike, is no proper evidence. This is really VERY unfortunate.
I feel like a spoilsport because I have agreed to a few Commons in my quite short time here - though there probably is no harm in that. So no need to remove your agreements!
I have read and read, talked to experts, posted a few and STILL believe it might be impossible to tell.
There are a good number of limpet Observations, is another of mine. Despite me making it easy for people to agree, there are still none.
And here is my only slightly more educated post in which I have written -

"It is very difficult to find definitive information which allows correct separation of the three most common ones and a huge overlap in descriptions of each. Book illustrations are somewhat vague and the internet is loaded with pictures which do nothing for separation."
Jan Light's "straightforward" Guide is here She writes "With practice it is possible to discern these differences and make accurate judgements based on exterior appearance but it is not foolproof even for the ‘experts’" Oh dear then!