Slugs are loathed in the garden and considered just plain icky by many people. Beyond the slime and the seedling-munching reputation lies a creature of surprising and secret habits! Tiger slugs, aka Spotted leopard slugs (Limax maximus), are a common species in Moscow. They are originally from Europe. Photo by Sarah Walker.

by Sarah Walker, from the June 2005 Newsletter

It’s been fun writing this column about beautiful city birds, trees, flowers and cute ladybugs. But now I’m going to write about slugs. Yep, the lowly slug, as in ‘you slug!’ or ‘that sluggard!’

Gliding out each evening along a path of slime, traveling 100 feet or more on one foot, shredding lettuce seedlings with its toothy tongue, then at dawn, following its slime trail back to its hiding place…. Slugs have a regular job just like all creatures, it’s just that they’re . . . slimy, and high on the list of garden pests. I’ll bet for many people, killing slugs is pretty automatic—and annoying, if you’re contributing precious microbrew to the cause! (Beer is a popular slug bait.)

Slugs are closely related to snails, sort of a snail without a shell. A shell is nice because the snail can get inside it when a hungry bird or mouse comes by. But owning and maintaining a shell means having to live where calcium is present in the environment. Slugs, with only a bit of a remnant shell hidden inside, can live more places than snails, and they can crawl into smaller places to get out of the sun.

To make up for their naked vulnerability, slugs wait until evening to go about their slugly business. It’s safer for them to stay hidden during the daytime while birds and other predators are active. Slugs hide in shady, cool spots under leaves or boards, or sometimes in worm holes in the soil which can be dangerous during heavy rains because slugs can drown. Slugs might crawl to safety on sidewalks to escape flooding, but then they’re prey to desiccation, or the dreaded terminal bootsole syndrome.

Slime, or the even grosser term, mucus, is everything to a slug. Slime can be sticky or watery—it depends on the occasion. Slugs can use slime to make themselves icky to predators, even humans: you pick one up, and eee--yew, you flick it away, shuddering. Then you can’t get that stuff off your hands. You don’t touch the next one!

Nasty slime tastes bad to a dog. Thick slime gums up a predator’s mouth. Numbing slime repels predators. A German slug researcher who licked one said even three glasses of whiskey couldn’t get the taste out of his mouth!

Slugs use foot slime to get around easier, sort of like dance wax. Lay down a good carpet of slime and glide right over dry rough ground, sharp edges or vertical surfaces, then use that trail to find home.

And, well, slime is the elixir of slug love. When two tiger slugs’ slime trails cross, and they decide ‘this is it, let’s take the plunge’ (commitment takes a long time, of course), they do exactly that: entwined, they rappel off a branch on a bungie cord of slime together to copulate in mid-air. Slug sex organs, which are quite large, are kept inside their bodies until this magic moment. The lovesick slugs evert them to the outside, through a hole near their head.

This takes a while, too, and seems like the drab land slug’s big opportunity to become as arresting as their brightly colored and widely accepted cousins, the beautiful sea slugs. Tiger slugs’ reproductive organs are a stunning and translucent glacial blue color, “like ice in a cave” one observer gushed.

Those few who have witnessed slug-love are quite taken aback and some have posted photos on Web sites. Check out Oregon State Extension. Follow links to “spotted leopard slug.”

Kelly Kingsland and her daughter Kate stayed up late at night once to watch two tiger slugs mating. It took a long time as weird thing after weird thing unrolled before their startled eyes. Kelly, whose farm produces organic vegetables and whose livelihood depends on slug-free gardens, said, “after I saw that, I couldn’t kill those slugs, I just couldn’t.”

Copyright: Copyright on articles, recipes and images are jointly held by the Moscow Food Co-op and the respective contributors, except were otherwise noted.

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