Leopard Slug
Giant Slug or Leopard Slug (Limax maximus) is a European species now found in North America and Australia. It is in the family Limacidae which is comprised of the keel back slugs. Keel back slugs are longer and thinner than the round back slugs that make up the family Arionidae. Keel back slugs also possess an internal shell under their mantle shield. The mantle shield is the section of the slug closest to their “head.” On the slug’s right side is their respiratory opening.
Slug anatomy
Front of Leopard Slug
I found Leopard Slugs at the Royal Oak Arboretum behind the Senior Center in Royal Oak, Michigan. They come out when it is getting dark and are active throughout the night. They are 10-15cm (4-6 inches) long. Eating mainly fungus, dead vegetation, and other slugs they are not normally garden pests unless the population is large. I was surprised at how fast they moved. I timed one crossing a 1.5m (6 foot) path in 15 seconds.
Leopard Slug at full stretch
For more information on this slug and other gastropods check out Robert Nordsieck’s great website The Living World of Molluscs. The Leopard Slugs are here.
Copyright 2014 by Donald Drife
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Where exactly in the Royal Oak Arboretum did you find the leopard slug? How common are they? I am looking for large slugs to feed my slug eating snake and these look yummy (to a slug eating snake)
The Arboretum is behind the Senior Center in Royal Oak. I’ve seen the slugs crossing the path that parallels the parking lot on the north end. The path is only 5 feet from the parking lot. I’ve never seen more than 2 or 3 slugs at a time.
I’m up in St Ignace MI can find them crawling around shaded damp areas.
I live in Roseville, Mi and we have 2 baby leopard slugs and 1 adult one that hang out at our house every night. They are so cool to look at! I just wonder why they love our house area so much?
You just may live in a lucky house 🙂
Found several on our trash bag last night July 3rd 2017. They are increasing in number just on my little plot of the neighborhood.
I am in Harper woods and for the last two nights that I have actually paid attention I have seen one nice size one in the exact same spot wish I could share the pic… where do they come from? Can you catch them? Lol 😝 What do u feed them?
They were imported from Europe. You can catch them but I have no idea what to feed them. I think they like mushrooms, perhaps they would like some nice shiitake. LOL
Found a leopard slug like 5 inches long about 2 weeks ago under my herb garden raised boxes was picking up boxes cleaning them out for fall he was under the box. omg freaked out didn’t know what it was. Asked husband he said it was a slug
They are all over in Trenton… 3 sometimes 4 on my porch every night for the past few weeks… What can we do about this??
I would just ignore them. They eat other slugs and not garden plants.
October 16th, Monday morning at 5AM on my back screen door window. Scared the Crap out of me. I took it off the window and put it in my flowerbed, the next day at 8am it was in my backyard, so I took a picture of it.
Holy Moly! I’ve never seen anything like this before.
I keep on finding them in my house. They are everywhere around here. I live not too far from a lake and there is a swamp area. I just now threw another one put side. Probably a good 5.5 inches.
Coldwater MI here, just ran across two on my back deck. They were climbing my screen door. Fun to watch.
Saw one on my boardwalk to Black Lake near Onaway, Michigan a couple of weeks ago. Had never seen this large of a slug before and glad to be able to identify it thanks to your blog.
In Birmingham, I saw 2 leopard slugs early yesterday morning while walking my dogs. They were on a fence a block from my home. I’ve never seen anything like them here before. Reading about them, I don’t think I should be concerned or that they should be eradicated. Am I correct ?
thanks,
Stephanie
I would not be concerned.
So yesterday I found a slug that is different from the horrid yellow-orangish things destroying my flower garden. It looked like the photos of leopard slugs but was small, about two inches long and 3/8 inch around. A baby leopard perhaps? Or is there a smaller variety similar to the leopards?
It was probably a young leopard slug. They take two years to mature.
Just came across 5 leopard slugs today at the Royal Oak Arboretum. They were living in a rotted out cherry tree that we cut down today. We were amazed by them.
Southgate MI here, I’ve just seen one of these outside, I’d never seen a slug this big in person before. They’re so fast, and I didn’t know we have big slugs like that here ! I was on my way home from work and I just had to kneel down and watch it for 5 minutes, it was so cool. Thank you for helping me identify what I was looking at.
I have numerous leopard slugs on our property in Brooklyn MI.