Slow worms. Our greatest ally in the war on slugs.
Almost no other animal on our shores goes through as many slugs in it’s lifetime as the humble slow worm. Anguis fragilis lives a fossorial life. Seldom seen as a result of their habit of remaining under cover. Be it in dense vegetation, in burrows made by small mammals or under the cover of debris such as logs, stones or, a text book favourite, sheets of corrugated tin. Compost heaps or grass piles are also favoured by slow worms and their distant cousins, grass snakes. Slow worms are actually lizards. Their skeletons reveal vestigial shoulder blades and pelvic girdles, where once limbs would have been attached. Over time and possibly as a result of favouring slugs they have gradually done away with their limbs. Some features remain which give away their identity as lizards such as a flat tongue with a shallow fork and eyelids. Snakes can’t blink! Slow worms and other lizards, bar some geckos, can.
Slow worms are surprisingly long lived for such small creatures with old records of captive
into their sixties. An average age in the wild would probably be more in the region of thirty years
or so. So thirty years of slug consumption certainly adds up.
So how can I get hold of some slow worms? I hear you all asking. Well, as they are protected
by law, against illegal collecting, being kept in captivity, being sold, disturbed, captured, injured
or killed, you cant. However, they are wide spread so you can offer them some habitat features
which might encourage them to adopt your garden or allotment as a place to forage for molluscs.
Resembling short lengths of copper tubing and not reaching much more than fifty centimetres long slow worms
can go unnoticed in an area for years. They seldom bask openly in sunshine, preferring to coil in dense
vegetation with perhaps only small portions of their bodies exposed. Warm evenings preceded by rain will bring them out from under cover to hunt for each other in order to mate during March and April as well as for food.
They give birth to live young in late July and August. Females are generally larger then males and have dark flanks and a thin dorsal stripe. Males tend to become uniform in colour as they age. The young are born with the colouration of the females. Unlike adders and grass snakes, which have keeled scales, slow worms are smooth scaled and this results in them having an almost metallic sheen. They can be coppery, brown or grey.
As mentioned, they like to hide, which makes providing shelter the easiest option for gardeners. A pile of substantial logs or flat stones in a sheltered sunny corner would offer opportunities for foraging and shelter. A tin sheet left on a few inches of cut vegetation or a grass pile covered with a piece of carpet or tarpaulin held down with logs would be fantastic. This would give them somewhere warm to shelter and give birth to their young, as well as attracting slugs right to them. The perfect B&B you might say. What ever you provide must remain undisturbed for as long as possible as too much interference will see them off. These are shy creatures who survive for many years by not being seen. They are popular food items on the lists of many other animals such as pheasant, buzzard, weasel, stoat, hedgehog, badger, heron, most corvids, chickens and domestic cats.
As with so many of our native reptiles they are in decline across the UK so anything we can do to create some form of refuge for these valuable garden predators is worthwhile. Those of you living in rural settings who have populations of these fabulous animals should treasure them. I bet your hostas are grateful.
For those of you without a local supply of Britain’s best slug munchers, other organic anti slug
options are available. I use porridge oats instead of pellets. I don’t care what the labels on these
pellet tins say, those sorts of chemicals in the food chain cant be good.
Porridge oats can be bought very cheaply. The slugs eat them, become bloated and pop their clog.
(Note the use of the singular clog as opposed to the plural clogs. Molluscs only have one foot,
I don’t want to be had up by any grammar Nazis or mollusc anatomy nuts for incorrect
information.) If the dead slug is then eaten by another predator up the food chain then no harm
will come to them. Hide your oats under a flat stone or in an orange skin so they don’t swell up in the rain.
Slugs love to shelter under stones and are attracted to the peels of citrus fruits. The old beer trap system works
well but having used them myself years ago, I found it a grim task to empty them out. A shallow plastic or glass
dish sunk into the soil and half filled with cheap beer will attract in the slugs and snails.
They drink themselves to death apparently.
Other slug predators are ground beetles, those shiny, black, fast moving ones you find under stones. Centipedes, frogs, toads and newts who will all appreciate a log pile or covered grass pile. Shrews enjoy the occasional slug but also prefer worms. Blackbirds and thrushes will tackle quite large slugs but do tend to spend most of the time wiping their beaks on the ground trying to get rid of the slime. Hedgehogs will also eat slugs but again prefer worms and cat food.
Getting back to the stars of the article, as the vice chair of the North East Reptile and Amphibian Group NERAG, I am keen to get records of any sightings of slow worms in the North East so please feel free to contact me with any reptile related observations you have made. These animals are grossly under recorded and little is known about their distribution or habits.
All information will be taken in confidence.
Enjoy your gardens, and enjoy the native wild life that shares your space. After all they were there long before your garden or house. We are all living on what was once green space at some point. Many of our native neighbours are of benefit in the great scheme of things and to interfere with the balance can cause long term damage to these often delicate systems.