Slime, Snails and Banana Slug trails...

Every morning I walk outside and look down (naturalists are always looking down or up, rarely sideways).  I see the mucosal tracks glistening beneath my feet.  Arion ater was here last night!

How do I know it was the European black slug and not another species?  Well, because I've met Arion before, in this very spot.  And this European he-she is a likely candidate here in suburbia, with the slime trail leading right back to the surrounding garden.  This is the species that is eating your pansies and garden vegetables.  They have color variants, usually black upon maturity, some chocolate brown and even a white version.  I've even seen orange ones with a bright orange skirt.  Yes, slugs have skirts.  Check out the foot fringe on the slug parts sketch below!

"They call me mellow-yellow..."

Quite rightly! The most popular slug in town is, of course, the Banana Slug (Ariolimax columbianus).  You've heard of this slug, oui?  The color can be like that of a banana - yellow with black spots - but they have wide color variation.  I've seen 'em all shades of yellow, spots, no spots, olive green, and even brown.  I've seen big ones over 6 inches long and even cutie-patootie tiny baby banana slugs (and yes a baby slug can be called "cute.")

I don't know if their popularity is based on their personality (mellow-yellow), size (can be over 9 inches long!) or because they are named after a banana (and bananas are awesome), but Banana Slugs are most beloved.

Sensational Slug facts:

-snails and slugs are cousins, snails are like slugs with shells

-they are detritovores = decomposers (aka: eat dead stuff and turn it back into soil)

-get around on one foot, called a pseudopod (or "false foot")

-hermaphrodites = both male and female parts 

-2 pairs of tentacula, 1 pair are eye stalks and the other are feelers

-the Banana Slug is the 2nd largest terrestrial slug in the world

The IMAX of Limax...

The largest terrestrial slug on Planet Earth is Limax cinereoniger, a European keeled-back slug.  They can grow to a whopping foot long!

Challenge:  How do slugs reproduce as hermaphrodites?  Think about it and then check out this video:  http://www.youtube.com/watch?v=GSW9kWIRCOQ

You may never be the same after watching it.  Or at least have a newfound appreciation for acrobats. 

That fab slug mucus tastes bad and many predators avoid it.  The slug-lovin' IslandWood staff and students can sometimes be found licking or kissing banana slugs.  No, they do not have a banana-like flavor.  Some people report a numbing sensation on their tongue or lips from the analgesic properties of the slime.  Of course, slug slime isn't just a defense mechanism.  It's also used for:

-locomotion

-reproduction

-and locks in moisture better than Chapstick! Though if I see you moisturizing your lips with a slug, I will worry about you.

Staying moist is essential for a slug.  Which brings me to my Slug Myth segment.

Myth:  Slugs dissolve with salt.

Status: True

Slugs dissolve if you pour salt on them because of osmosis.  A slug's body is made up of mostly water, and its skin is a very permeable membrane.  This is why you will see more slugs around now than during the dry summer days- they need to stay moist or they die.  When salt crystals come in contact with a slug body, the water inside the slug is drawn up out of the slug to dissolve the salt.  The slug is effectively dehydrating into a pile of slushy salty water and proteins.  Pesky slugs have long met their demise with table salt.  This is a slow and painful way for a slug to die and not recommended!  Here are some cruelty-free ways to repel slugs that don't involve salt, poisons or embedding copper wire into your garden.

Marigolds or rosemary planted throughout a garden are natural slug repellent plants. You can mulch with seaweed (slugs will avoid the salty seaweed) or diatomaceous earth (slugs will avoid this crunchy material comprised of fossilized ancient diatoms, our equivalent of walking on broken glass).  Unless of course your garden slugs are herb-loving, seaweed-slurping, adrenaline junkies. 

Christina's 2 cents:

Get to know your neighborhood slugs.  Certain species roam about only during the night, others by day.  Find some slug eggs under a pile of leaves and notice how dainty they are.  Lick a slug.  Do leopard slugs have a different flavor than black slugs?  Ewww, just kidding.  Put a slug on a clear glass dish and look underneath.  The muscular foot action propels the slug along... groovy!  Or if you're feelin' sassy, put a banana slug on a banana peel and take a picture.  The irony would be lost on the slug, of course, but left overnight he may eat the peel!