“Mate, the state of you.” Peter Cooper, an ecologist and species reintroduction specialist, is performing a delicate operation, using the tip of a fine paintbrush to extract a succession of tiny creatures from the shell whorls of a deceased and deliquescing snail on which they are feasting. He transfers them to a scrap of cellulose foam on which several others already cling. The last one out, presumably the first in, needs some extra cleaning. “Oh my, look at you … fully lost in the sauce.”
The gooey gourmands are barely 5mm long, with dark grey, segmented bodies and tiny legs. They look a little like ladybird larvae, but they are in fact a creature not seen in this part of Yorkshire for 100 years, but described by the bohemian rambler and writer Edmund Bogg when he passed this way in 1909 as “wont to hang out their fieldstar lamps … as if lit by the hands of fairy folk”.
That magical depiction of glow-worms is somewhat at odds with the drab little grubs that Pete has reared in takeaway tubs for release around flooded gravel pits now managed by the Lower Ure Conservation Trust, and whose grisly feeding habits he is now recounting.
In captivity he supplied them with live snails, but from today they will have to hunt their own prey, crawling aboard the shell, then reaching from the rim to deliver a venomous bite, usually to the soft flesh of the eyestalk. Pete also explains why reintroduction is necessary – adult females are flightless, and the winged males very weak flyers. Once gone from a locale, they struggle to recolonise naturally, and hence their lights have gone out over much of the country, largely owing to the loss of scruffy banks of rank vegetation like this one.
About 450 larvae are deposited on sun-dappled verges edged with willowherbs and brambles – good places for snails and their new predators. It feels like a fitting act of restoration at equinox‑tide, of little lights to balance the gathering dark. With luck, adult females will be illuminating the banks two summers hence, but we won’t know for sure that a breeding population has established until 2028 or 2029. Summoning fairy folk requires patience as well as expertise.
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