Travel Reference
In-Depth Information
Look Out: Banana Slugs Crossing
If you happen to be a gardener who lives where summers are humid,
you probably curse slugs, which can do immense damage to a veg-
etable patch. Now, imagine that those slimy little slugs chomping on
your tomatoes are not an inch long, but a foot in length! Sound like a
late-night monster movie? Think again. And if you go into the woods
today, be sure to watch your step.
The banana slug
(Ariolimax columbianus),
which can grow to be a
foot long and live for up to 5 years, is the only slug native to the Pacific
Northwest. Making its yellowish, elongated way through the region's
lowland forests, these slugs dine on plants, mushrooms, and decaying
vegetable matter. Though slugs may seem to wander aimlessly, they
have two eyes on the ends of long stalks and two olfactory organs on
short stalks. The eyes detect light and dark and help them find cool
dark places where they can sleep away the day, while the olfactory
organs are used to locate food. A slug eats by shredding organic mat-
ter with a tonguelike structure called a radula, which is covered with
thousands of tiny teeth.
Aside from their repulsive appearance and annoying habit of devour-
ing gardens, slugs get a bad rap for sliming anyone unlucky enough to
grab one accidentally. Slug slime, if you take the time to study it (instead
of just rubbing your fingers furiously to remove it), is amazing stuff.
It's at once as slippery as soap and as sticky as glue, an unusual combi-
nation of properties that allows slugs to use their slime as a sort of
instant highway on which to travel. Secreting the slime from their chin
like so much drool, slugs coat the surface of whatever they're crawling
on and then just slide along.
Slug slime may also serve as a defense mechanism. Lacking the pro-
tective shell of their close relatives the snails, slugs defend themselves
by secreting copious amounts of slime, rendering them unpalatable to
predators such as shrews, beetles, crows, and garter snakes.
Think slugs are sluggish? Think again. One of these babies can do
0.007 mph (3-4 in. per min.) on the straightaway as the muscles along
its foot constrict in waves and move it forward.
It's hard to believe that something as soft and slow moving as a slug
could ever be a threat to anything, but slugs are real scrappers. That
same serrated tongue that shreds lettuce so efficiently can also be used
as a weapon against other slugs. If you start checking slugs closely,
you're likely to find a few with old battle scars on their backs.
We know that birds do it and bees do it, but how do slugs do it?
With any slug they chance to meet, if the mood strikes. Slugs are her-
maphroditic, and they can mate with any other slug of the same species.
What this means is that each one of those slugs out in your garden is
capable of laying eggs!
And how did banana slugs get their name? No one is quite sure
whether it's because they so closely resemble bananas, right down to
the brown spots, or because when stepped on, they have an effect sim-
ilar to that of a banana peel. Either way, it's an appropriate name.
