Showbiz Slugs

Last November I joined 59 other volunteers in a project monitoring the slugs in our gardens. Our Slug Count Survey was being run by the lovely Imogen as part of her PhD with the RHS and Newcastle University. Once every 4 weeks we had to go out into our gardens and collect all the slugs we could find in half an hour. We’d then attempt to identify them, before posting them off to Imogen for “proper” identifications.

This year has flown passed for any number of reasons, but I still can’t believe my year of slug counting is already up. It took a bit of explaining to my neighbours as to why I went out each month with a head torch in the dark to wander round the garden with a bucket of carrot shavings (food for the slugs) for half an hour, not to mention explaining to the lovely lady in the post office why I was posting slugs! I actually found it really interesting to go out in the garden after dark and just look at what was around. I was used to going out to check on the moth trap, or feed the hedgehogs, but tended to be focussed on those activities. Searching for slugs, I noticed for the first time all the caterpillars that were out and active, the worms on the grass that vanished as they felt my footsteps approach and the spiders and woodlice and all manner of other species going about their business at night. The garden at night becomes a whole other world.

In total over the 13 counts, I sent off an amazing 1145 slugs! You’d think that might have reduced the population in my garden, but they are still very abundant. Going out the night after a count there seemed to be just as many slugs roaming the garden as before, with no sign of diminishing populations.

And the slugs themselves were clearly doing their bit to increase numbers.  Through September there were several nights when I saw pairs of large Arion slugs trailing each other round the grass. There is clearly a season for it, as I saw multiple pairs for a couple of weeks, but none before or since.

Whatever romancing was involved, it was clearly successful and I can presumably expect more Arion slugs next year.

As well as getting to see a bit of slug romance, I was really chuffed to film one of the Arion slugs getting its wriggle on. This squirming action in the video below is a characteristic feature of a couple of Arion species when disturbed.

The total number of species recorded has yet to be finalised (some are apparently getting sent for DNA analysis!), but is probably around 14. There were at least 4 species of short-keeled slugs, including this Ambigolimax sp.

There were at least 7 species of round-backed slugs including the familiar large Arion species. Finally there were 3 species of the long-keeled slugs. The one below is the Crimean Keeled Slug (Tandonia cristata) which has a network of dark lines criss-crossing the body.

My most unusual find was a Worm Slug (Boettgerilla pallens), another long-keeled slug, which as the name suggests looks like a worm! I only found 1 in all the surveys.

Finding the worm slug was good, but the best was yet to come. Our survey leader appeared on BBC’s Gardener’s World in July to try and convince the (possibly sceptical) viewing public of the delights of slugs. As part of the feature there was footage of several specimens. I was beyond excited when she told me that one of my actual slugs had been filmed for the show. Here’s a still from iPlayer showing my very own slug TV star (a Netted Field Slug, Deroceras reticulatum).

Not only did my slug feature, but it was described as being one of the biggest pest species, doing the most damage to plants. I don’t know why, but I felt ridiculously pleased that I’d got effectively the bad boy of the slug world!

So all in all this slug project has been fascinating. I love doing these citizen science projects. You usually learn something new, or see something new and either way you get the pleasure of enjoying some aspect of nature whilst contributing hopefully useful data to scientists. This particular project has given me a whole new appreciation for slugs, a group I’d previously given little thought to. I know they are not popular with gardeners and they can be a worry for those with hedgehogs in their gardens (slugs can carry parasites such as fluke and lungworm which can pass to the hedgehogs). But everything has its place and slugs have just as much right to be in a garden as everything else.