Observing Giant Urban Slugs

Observing Giant Urban Slugs

In November I received an e-mail from a resident of Etobicoke, asking for information about large pumpkin coloured slugs encountered on a sidewalk as she walked her daughter to school.

It seems that my paintings of live slugs, native and introduced, and my recent training and mentoring by  Swiss slug expert Ulrich Schnepatt, has made me the Canadian specialist in this case! Not only did I receive a shipment of the slugs in question to observe, photograph, preserve, and dissect in the process of discovering their identity, but a cascade of excitement about giant slugs ensued!

First, I was contacted by a writer for the Toronto Star, and we got an excellent article written about the mysterious new-to-science occurrence of giant orange slugs in Toronto. You can read the article here.

Immediately a steady stream of e-mails began (totalling 30 in two weeks), reporting sightings of giant slugs of two kinds (the big Arion, and the Leopard Slug, Limax maximus) from Oakville to Bowmanville, and Rockwood to Wiarton – even one from Sudbury!  One from Croatia, and a photo taken in England.

In the midst of this excitement, the Royal Ontario Museum contacted me, asking for specimens, and Canadian Geographic Magazine plans to feature the public interest in these exotic creatures with a feature on citizen science in the June issue.

Our friend Kari Gunson, the road ecologist, made a map for me of all the localities reported in everyone’s e-mails, and it looks like this:


I have thoroughly enjoyed the first stage of this investigation, and invite everyone to participate – put your slugs on the map!  The next stage will be site visits in the summer of 2010, to photograph and collect.

Slugs are fascinating, and GIANT slugs are astonishing!  I have been watching them explore their surroundings, eat, and grow – and even lay eggs.  Presently Philip and I are drawing and photographing the development of tiny slug embryos in clear-as-glass Limax eggs.

If you see a slug that is 5 centimetres or more, collect it or photograph it, send me a comment on this blog or e-mail me, Aleta Karstad - and together we’ll find out who these European introductions are, and how far they have spread.

I’ll see you all in the summer, as we re-visit all the places we’ve been across Ontario in the first stage of the 30 Years Later Expedition.

To see more of our slug project, visit www.pinicola.ca/slugwork.htm