By Kim Maley, Park Interpreter

Nature is weird. Yes, we all know and love our “normal” critters that have logical anatomy and relatively predictable behavior patterns. I could write all day about lions and tigers and bears (oh my!). But what about the creatures that seem to be more science fiction than reality? This article is devoted to such a creature. Picture a creature with:

Allow me to introduce you to the very real and fascinating Ariolimax columbianus or Pacific Banana slug!

Before you wrinkle your nose and think only of slimy garden pests, consider a few of their fascinating attributes:

Slime is good! Slugs are hygroscopic. The 2 types of slime they produce have specific functions. The thicker slime is a defense mechanism or what I like to call the “Ewww” factor. Not only a repellent to humans like my mother, this toxic slippery slime makes the slug difficult to hold on to and an unpleasant experience to taste. In fact, garter snakes and Pacific giant salamanders are among the few predators immune to the toxic slime. I would not recommend joining those people who fancy licking slugs for the tongue-numbing effect! The thinner slime produced is, interestingly enough, how slugs flirt! Chock full of pheromones, this slime literally paves the way to a genetic exchange. Which brings us to the next slug fun fact:
Slugs are hermaphrodites - each have both male and female genetic exchanging equipment. Some species are able to self-fertilize but the Banana Slug may be happy to report they are not among that category. However, slug reproduction is not without its own type of drama! Along with the suggestive slime, slugs are equipped with “love darts” with which they indicate their intentions. Each slug will then extend a male reproductive organ (which can be longer than the slug!) to intertwine with the other’s to transfer genetic material. Each will then slither off to lay their fertilized eggs but not before a rather disturbing battle in which one of the slugs will never again reproduce. Look it up. It’s gross.
Banana slugs can grow up to 9 inches and can move at a brisk pace of 3-4 inches per minute. The current known record holder clocks in at a whopping 6 inches per minute! Coastal banana slugs are larger than we have here at Silver Falls are more commonly yellow. Color variations are dictated by diet, light, and moisture. Colors can be yellow, green, gray, reddish brown and can be with or without spots.

Oregon is host to several slug species, including over a dozen exotic or invasive species (i.e. the ones likely found eating your garden vegetables). Our friendly Ariolimax columbianus, however, is one of the most iconic in the Pacific Northwest and has the important task of consuming dead and decaying matter, animal feces, and fungus and turning it into the rich soil that sustains our forests.