Amongst all the stories of dire consequences relating to wildlife resulting from this year’s weather, there is one which will give gardeners pause for thought.
It concerns the so-called Spanish slug, which is native to central Europe in general. The slug was first recorded in this country in 1954 and is now well established alongside our 30 or so native species. Most of these are not pests, but vital members of the garden ecosystem, consuming dead plant material and other detritus. All of the slugs have found the warm and wet conditions this year much to their liking.
The Spanish slug is considered to be in the top 100 worst invasive species in Europe. It is castigated by scientists and horticulturalists alike, and demonised in the press with all the usual evil traits reserved for foreign species that are neither pretty nor useful. Simple facts are turned into scary features: it is described as ‘giant’, being about 10cms long, ‘voracious’ - but it does have to feed, ‘a cannibal’ because, like many other animals, it will consume the remains of its own species, ‘alien’ because that is the most pejorative word we use for anything from another part of the world.
Other crimes include causing traffic accidents when cars skid on the slimy remains of slugs run over by other cars, although that seems to me to be a case of more sinned against than sinning, and being able to smell food from 60 cms away – that’s two feet!
The Spanish slug does have a lot going for it though. It resists drought better than our native slugs and so will thrive whatever the weather. It lays about four times more eggs than other slugs, and will also interbreed with some native species to produce a sort of ‘superslug’ resistant to cold temperatures.
The despair of gardeners faced with this unwelcome visitor is something of an irony. Its population in Britain is constantly bolstered by the arrival of more and more individuals, and one source of these is the horticultural trade. There is a continuous flow of potted plants arriving from continental nurseries.
The soil in those pots harbours many creatures, including slugs and their eggs. The very people who rue their presence are the ones partly responsible for them being here. Another factor is the importation of fresh fruit and veg which can be in your house, complete with stowaway slugs, within a day or two of being picked in France or Spain.
The best thing to do in the face of this new threat to our hostas and salads is to practice good garden hygiene, water in the morning rather than the evening, and encourage the slug’s enemies, such as blackbirds, thrushes, frogs and hedgehogs.