The lowly worm

Dear Khortney,

I was wondering if you've heard of invasive earthworms. Should I prepare? Should I expect them in my house? Please advise. That, and more, that I'll ask in person.

~A Librarian

Dear Madame Librarian,

Oh, the beloved earthworm. Everyone loves them, until they feel unloved, at which point they go eat them. I prefer chocolate eclairs, but that's just me.

Yes, add earthworms to the list that includes starlings, bullfrogs, and domestic cats as invaders that wreak havoc on the environment. There are at least 5 native genera of worms in this state, but many, many more non-natives.  There isn't too much study of the earthworm because, well, I guess birds are more colorful.  We know way more about the avians than the annelids.

We ecologist types are sort of sweet on the late holocene, and want everything to stay as it was approximately 400 ish yars ago, before European immigrants arrived.  We confuse ourselves with this, because we also think Darwin was one of the greatest contributers to science of all time.  I know, it's complicated, but the gist is, we believe in evolution, but don't really want to see change in ecosystems.  I'm one of those people, so let's just skip ahead (or back, if you will), to the earthworm.  Wait, let's not skip just yet.  It's rapid change that's troubling. 

The earthworms came to this country as illegal immigrants; in Arizona they need to carry papers with them at all times.  Worms snuck in with plants, people, and soil from other lands, mostly Europe.  Earthworms were used as ballast in boats crossing the ocean blue.  Okay, the soil was used as the ballast, and the earthworms snuck in, much like the Vietnamese Boat People.  Fishermen are thought to be culprits in the Worm Invasion too, because they take worms out fishing for the day, and if the worms don't catch anything, they throw them on the ground. 

The biggest impact of the invasive worm is happening in the Great Lakes Region, where the little guys chomp through the leaf litter quickly (in 4 weeks rather than the typical 4 years it would take for the leaves to decompose without the little wormies.)  This eliminates vital habitat for small shrubs and the little herby plants that we all love so well, like wild ginger and trillium.  The mystery that I can't solve here is this:  in Minnesota, they say they have no native earthworms, due to the glaciers.  But we do claim native earthworms here in Washington, so maybe we're just more about the holocene than those Minnesotans.  By the way, Minnesota's state motto is, L’Étoile du Nord ; Wikipedia says means "We hate mountains," which just goes to show you that you can't always trust an encyclopedia that any random person can edit.

The point of all this, Madame Librarian, is that yes, you should prepare.  You should make a team, seal off your doors, and learn worm grunting to distract them from the invasion.  Sure, I'd love to be on your team, thanks for asking. 

I hope I've even come a tiny bit close to answering your questions.

xoxo,
N'3lvra

P.S.  In the juvenile literature section, I was able to find a book with science fair projects involving earthworms.  I know!!  I can hardly wait, and if all goes well with the worm grunting, I'll be writing more about that.






http://www.wired.com/wiredscience/2008/10/darwin-earthwor/