Saturday, June 2, 2012

Inside A Cecropia Moth Cocoon

A Cecropia Moth's cocoon is rather drab and uninteresting.
It's what's inside that counts... and makes the cocoon more than just a large blob hanging on a branch.
 I've been seeing giant silkmoths fluttering around the last few weeks, and they reminded me of many years ago when I found a pair of Cecropia Moths.  The pair were on the ground. Specifically, they were on the driveway of the campground where we were staying.  My kids were totally impressed with those giant silkmoths.
We placed them in a tree.. it would be a shame for something to drive over such beautiful moths.
Cecropia Moths are as huge as they are magnificent!

Earlier this spring, I brought a Cecropia cocoon into the house to see if a moth would eventually emerge.
   Recently,  I had taken the cocoon out of its jar in order to show it to some friends... telling them that soon a beautiful Cecropia Moth will emerge... when my son noticed something peering out of a small hole in the side of the cocoon. We could see something was trying to get out.
The next day, instead of a beautiful giant silkmoth... out came a bunch of ichneuminoid wasps
These wasp's larvae (Gambrus sp.) had devoured (parasitized) the Cecropia.
   A few days after the wasps emerged, I wanted to see what was going on inside the cocoon, so I cut along one edge of the outer layer of the cocoon and rolled it back.  Inside that outer "shell" was another layer of the cocoon.
 Notice the exit hole in the inner part of the cocoon.
 Inside the inner cocoon were about twenty-five tightly-packed, smaller cocoons of the parasitic wasps, along with remnants of the Cecropia Moth.
   After about a dozen of the wasps had emerged from the Cecropia cocoon and nothing more happened, I decided to open up the cocoon.  Many of the remaining parasitic wasps had fully developed but died inside the moth's cocoon or even inside their own cocoons. I suppose the conditions in the jar or house were not conducive to their emergence.

"hatching" parasitic wasps in place of a Cecropia was somewhat disappointing...
... and a bit creepy...
Nevertheless, the wasps were colorful and intriguing...
... just not as magnificent as a Cecropia Moth.

1 comment:

  1. Oh Dana, I wish I'd seen one of those moths emerge, but still it was an adventure and an education ...

    I wonder if those moths live in Nova Scotia ? I'll have to check Mr. Google. OK. I'm back. Did u miss me ? Mr. Google says they're found in southern Canada. I sure hope I get to see one one day.

    Well, last year you showed me a salamander egg mass, and this year I got to hold one in my hand ... so ya never know.