With all the rain this last week, my garden is looking rather soggy and the slugs are loving it! I struggle keeping the enormous amounts of slugs off my favourite hostas and slugs are not my most favourite of creatures. They even manage to come under the skirting boards in my hall and slime their way across my quarry tiles…. not pleasant when you stand on one in bare feet!
Trying to overcome my lack of love for these slimy visitors, I have decided to do a blog post on them and to try to find a little more about them. I found a brilliant website called Slug Watch and most of my information is from there.
There are approximately 30 species of slug in the UK. On average a UK garden is home to over 20,000 slugs and it is estimated that an acre of farmland can support over 250,000 slugs.
Slugs move in rhythmic waves by contracting muscles on the underside of the foot. At the same time a layer of mucus is produced that helps to smooth the slugs path across the ground. This mucus is also used as the slugs navigation system, as slugs will find their way back to their tunnels and feeding sites by following their mucus trail.
A slug has two retractable pairs of tentacles. The upper pair of tentacles are called the optical tentacles and are the eyes of a slug. The optical tentacles have light sensitive eyespots on the end and can be re-grown if lost. These are also used for smell. The lower pair are two smaller tentacles and are used for feeling and tasting.
The mouth parts are below the tentacles and the slugs eat using a radula which is a tongue-like organ that is covered with approximately 27,000 tiny tooth-like protrusions that are called denticles.
Slugs have a large respiratory pore called the pneumostome. This leads to a single lung and is generally found on the right hand side.
The mantle is an area behind the head of the slug and is made of thicker flesh than the head. If a slug is frightened or not active the slug will retract its head into the mantle for protection. The mantle also forms the respiratory cavity. In some slug species there is a small piece of shell in the mantle, this is because slugs have evolved from snails.
The keel is a ridge that runs the length of the back of some species of slug.
The site even has Slug Trumps! I might use these with the kids at school!
Most of the slugs in my garden seem to be Arion rufus, the Large Red Slug. I am going to be looking out for other species as well. I have the black version of this slug , the Leopard Slug and the Common Garden Slug.
I may well do a photographic project over the summer based on these guys… maybe then I can become a little more fond of them!