Glow-worms and Slow worms

When is a worm not a worm?

When it’s a beetle or a lizard!

I imagine that very few readers have seen a glow-worm lately, but it’s possible there are small populations tucked away in Forncett, although their numbers have massively declined since the days when country folk would gather them as makeshift lanterns, and the poet, Andrew Marvell, referred to “Ye glow-worms, whose officious flame /To wandering mowers shows the way...”

 I last saw them locally eight years ago late on a summer night in gently managed, dark-sky grassland.  But the property changed hands and has been differently managed. I don’t know whether the colony survived. The good news is that another Forncett resident and FNM supporter has recorded them in her garden in June/July 2023 and shared her video footage with us. You can view it here.

The glow-worm is really a beetle (Lampyris noctiluca), the males being winged, and the females wingless, so the female cannot move much during her very short lifespan.  The adults don’t eat at all, (no mouth parts) so their energy must be conserved. The female emits a steady yellowish-green bioluminescent glow from the end of her body to attract a male.  After mating she stops glowing, then dies after her eggs are laid. When the eggs hatch they remain in larval form for one or two summers, depending on food availability; thus the number of adults developing each year can fluctuate. Larvae feed mostly on small snails, apparently paralysing them before sucking the soft insides out. 

glowworms.org.uksay “If you don’t already have glow-worms in your garden, there is no way of attracting them, any more than planting bamboo will attract pandas”; existing populations are quite static for reasons already mentioned, and even on an established site need sympathetic management to maintain the colony. A mosaic of weedy areas along with shorter grass in a snail-friendly damp area is ideal, along with no pesticides/herbicides and no nearby artificial light. June or July is the best time to look, around gardens, allotments, hedgerows, churchyards, verges etc. A red filter on a torch is ok, or search by a crescent moon. Do let us know if you spot any.You can report any sightings, confidentially, atglowworms.org.uk

Perhaps you’re more familiar with the slow worm? Again, not a worm; rather, these harmless creatures are legless lizards (Anguis fragilis). If you’re lucky you might have some in your garden or allotment, especially where there’s a nice warm compost heap, where they can hunt for tasty invertebrates during the evenings. Slow-worms like plenty of grass and plant cover to hide in. These cold-blooded reptiles love to sunbathe, and their favourite protected hotspot would be under some corrugated iron or onduline, or perhaps some pantiles.

Sometimes confused with a snake, the slow worm is smaller at 40-50cm, its body has no ‘neck’, it has blinking eyelids and a tail that sheds if seized; the tail will continue to wriggle to distract the predator.  Sadly, my first slow worm sighting, many years ago, was displayed in several sections, bitten into slices by a cat. They will be eaten by badgers, birds, foxes and hedgehogs.If a slow worm manages to escape predation it can live for 20 to 50 years.  The skin is gleaming metallic in appearance - greyish brown for males with blue dots in older specimens; brownish with darker sides and often a dark dorsal stripe for females.

Mating, a lengthy and lively affair of up to ten hours, starts in May. The female is oviviparous: she incubates the eggs internally and gives birth to up a dozen live hatchlings in late summer.  Slow worms hibernate from October to March, burrowing underground, sometimes in tree roots or in that compost heap. So please take care if digging your compost (grass snakes will lay their eggs there too). And as always, and for the sake of all wildlife, use strimmers only with the greatest care.

 Slow worms are a protected and priority species and it is an offence to harm or destroy them.

  June 2023