Missouri Master Naturalists- Springfield Plateau Chapter

Friday, June 22, 2012

Herding Cats

Ever have a friend ask if you will adopt a cat?  How about 170 cats?  And what if they are such good friends that you can't say no.

Promethea cats- late instar
Chris and Deb Barnhart raise a wide variety of butterfly and moth eggs for the Butterfly House and end up with lots of caterpillars, a.k.a. "cats" which voraciously feed on sacks of leaves.  Eventually they need to be farmed out to someone with more trees than sense.  That would be us.

We met at a local restaurant to make the exchange with Chris bringing them in a cooler.  Caterpillars are sensitive to drying out and the heat of a cooking car.  He had bags of Promethea, Polyphemus, and Luna silk moth cats.  Spoken in a restaurant, these words sound like new varieties of illegal "bath salts".  We received a lot of curious looks and left quickly with them before someone called the DEA.

Bull Mills bag lady
The technique of raising them from here on out is relatively simple.  Each of these moth caterpillar species has specific species of tree or bush that it feeds on.  We simply find one of the right size, cover a small tree or major branch with a fine mesh bag and add 5-10 cats, depending on their size.

They will live in the bag safe from predators, chomping the leaves until they pupate (form a cocoon).  We then come back after 2-4 weeks, remove the bag and collect the pupae.  These go the the Butterfly House at the Botanical Center where their emerging is a star attraction for visiting kids both young and old.

Promethea pictures by Chris Barnhart











  BAMONA  describes the interesting life cycle of these Promethea caterpillars:
"Males seek females in the afternoon and early evening, with most mating occurring from 4 PM to sunset. At night, females lay rows of 4-10 eggs on the upper side of host plant leaves. Young caterpillars feed together while older caterpillars are solitary. Older caterpillars do not eat the leaf midvein, but cut the leaf petiole at the base so it falls to the ground, perhaps a defensive measure eliminating visual or olfactory signs of feeding. A caterpillar ready to pupate strengthens a leaf petiole with silk and then spins its cocoon inside the curled leaf."
Today's bagging featured Promethea caterpillars* which feed on a variety of tree leaves including our spicebush and sassafras.  These will eventually emerge as a beautiful Promethea giant silk moth which lives only to breed and lay eggs for the next round of caterpillars.  It is so focused on reproduction that it doesn't eat- or even have a functioning intestinal tract!
* There were also Polyphemus to put on oaks and Luna for our walnuts.  The leaves will grow out again and no trees were significantly damaged in making this blog.