Medusa? Is that you?

Last Friday I decided to give Freckles a little break from arena work and headed out for some trail riding with friends Teresa and Jan.

We met up at the Wilson Creek Trailhead (the spot of misadventure where I most recently got Annabelle, Kristi and I lost for a couple of hours).  Usually at this time of year there a lots of wildflowers growing and water flowing down the creek beds, but our unusually dry spring has taken a toll on the desert flora, and there were only a few small (but still beautiful) bunches of flowers to be seen

Despite the lack of moisture there were some areas that were starting to green up, and it was refreshing and relaxing to just ride along, chatting as the horses’ feet crunched along the dry path.

About an hour into the ride, I noticed some kite-shaped whiteish thingies on a couple of the sagebrush that we rode by.  They didn’t look like much from a distance, almost like large dense spider webs.

As we went along though, the trail led up past a few that were a bit closer.

We sidled over for a closer look.

That’s when we saw dozens?…….hundreds?…….thousands?   Yes definitely thousands…… of caterpillars crawling out of a nest in a giant clump that looked a lot like the head of the famed Greek Gorgon, Medusa.  (No, I never saw her personally, but I did take something about Greek mythology in college…and I know how to type ‘Wikipedia’.)

One bush family had three or four of the nests on it, with caterpillar clumps in varying amounts of activity twining around.

The pictures don’t do them justice…….these things were curling and swirling and winding around on top of each other in a never-ending circle of motion.  It was kind of creepy.

None of us had ever seen such a sight before, and we sat in quiet contemplation for several minutes (yeah right, like we’re ever quiet!)  trying to make sense of the unusual nests in front of us.  Finally we rode off, with me promising to do some research and figure out just what the heck it was that we had seen.

The rest of the ride was nice and fairly uneventful.  We stopped along the way for a few pictures.

And of course I snapped and snapped as we rode along.

Pictures. I snapped pictures.

Miss Teresa on her trusty Remi climbed through the sagebrush with ease.

It was a lovely ride, and I know that Freckles enjoyed doing something out in the sunshine other than loping circles.

When I got home I got on the computer and looked up “caterpillar nest high desert Idaho” and came up with the answer.  The nests we had seen were made by hatching Western Tent Caterpillar Moths.

The mommy moth, my research found, lays 100-300 (OK – they LOOKED like thousands of) eggs sometime in the late spring or early summer.  The eggs soon begin to develop, but do not hatch until the following spring.  After hatching, the baby caterpillars all stay close together and function as a social unit as they feed and grow through the spring.  The group secretes silk to create the web-like structure that is called a tent.  They used this tent as a refuge from cold temperatures and predators.  The temperature inside the tent is more stable than that of the surrounding air, and can be several degrees warmer than the outside.

The little caterpillars journey out of the tent to find food, and if they find something particularly tasty, like a bunch of soft new leaves, they eat as much as they can, then secrete a chemical trail as they return to the tent so that their siblings can find the food too.  Very sharing of them.

After growing for about 8 weeks, the caterpillars form cocoons and about two weeks later turn into adult moths.

They look like this when they are grown up.

As adults they reproduce and then die, starting the whole life cycle over again.

Ladies and gentleman, that was your science lesson for today.

Kind of interesting huh?