Slugs: Lifespan?

[Paul]

In the link Anjie posted about snail reproduction the last paragraph says:

"Slugs, that usually do not become older than a year, lay their eggs mostly in autumn, so that the eggs are the stage that hibernates. Snails in contrary often hibernate and thus endure the cold times of winter."

Is that suggesting that a lot of slug species have very short life-spans or is it just referring to species that do have short life-spans?

How long do the various slugs live for?

[Kevin]

According to this link

www.fcps.k12.va.us/StratfordLandingES/Ecology/mpages/leopard_slug.htm

Leopard Slugs will live upto 3 years...Im assuming thats in the wild though, maybe slugs will live longer in captivity? as captive conditions would elimanate a lot of the factors that contribute to a wild slugs life expectancy wouldnt it?

[Paul]

Yes I agree, particularly because as far as I know, slugs don't hibernate which would cause longer life in wild snails because it is almost like suspended animation so they're using up less snail life

I have read that slugs aestivate though by creating a sack around them so perhaps they can hibernate. I just assumed they didn't because their slime contains an anti-freeze agent.

[Beth]

This is an interesting point, I have always wondered about the lifespan of slugs. I have observed in our vast garden population that after a winter there are very few very large slugs, but lots of very small ones, this reverses slowly and by the end of the Summer there are lots of huge slugs and very few little ones. So I had concluded that many of the large slugs died during the winter and that the eggs possibly over winter and hatch in the spring. Could cold weather slow down the development in the eggs? Our frog, toad and slow worm population will also be effecting the number and size of slug I see at different times of year. All these gorge themselves on the small slug population during the Summer months (the large slugs are too big for them to eat) So this would account for some of the decrease in small slug numbers during the Summer. They could well live a-lot longer in captivity.

Beth

[Paul]

That article does seem to suggest the eggs overwinter and hatch when the weather is a little warmer. It certainly explains your observations.