A strange little creature inhabits the bottom of limestone lakes and rivers in this country: the freshwater crayfish. It grows up to four inches in length and looks, Eamon de Buitlear tells us in his Ireland's Wild Countryside, just like a tiny lobster. It hides under stones and is slow-moving. This, Eamon says, makes it easy prey for the mink and otter.
An interesting point is that the female, instead of laying her eggs on the bed of the river or lake, carries them around attached to her body, where they eventually hatch. It has been said, with what authority is not clear, that the presence of these crayfish shows that the water is unpolluted, or relatively so. Anyway, on a river in Meath, where there was a regular deposit of otter spraints (excrement, on certain rocks, nearly always containing the remains of legs and other bodily portions of crayfish), there has recently been a total lack of such evidence.
Is it that the otter has changed his nightly tracks? Is it that the crayfish, normally spending the day mostly under stones, are now breeding, and thus more than ever in hiding? Or have they been wiped out either by otter and mink depreciations, or by pollution? Certainly where, a few years ago, bits of meat lowered into the normally most populated stretch, and securely tied to a strong, well weighed-down net, always gave results, now nothing.
Not even a bite-mark. More testing is needed, upriver or down, before any conclusions can be drawn. Eamon does mention a parasitic fungus as causing a decline in Midland lakes, but this is a swift-flowing river.
The greatest show of these normally discreet creatures was seen by some friends fishing the White Lake, up in Westmeath. Coming in at dusk from the deeper water, gliding over the white marl bottom near the shore, they noticed that the marl was no longer white it was almost black from the thousands of crayfish that had come out to hunt.
They are edible, but not tasty.
And it seems such a pity to boil to redness such a tiny creature, especially if they are in decline (or even if they're not in decline.) On the Continent, freshwater crayfish are much bigger and at one time, were, and still may be, considered a great delicacy, perhaps especially in Poland.