I’ve been up in at Lake Tahoe for the last week for my birthday. On a whim, I brought a container of Polyphemus ova of whose viability I was unsure of — but i strongly suspected they we infertile because I hadn’t witnessed a pairing that might have produced them. The eggs came from the moth that was in a mating cage when I found traces of a dead moth eaten by a raccoon. On the morning of July 5th, the container was swarming with caterpillars! My guess is that the moth that laid the eggs was mating with a wild male when a raccoon ate him, luckily after she had been fertilised.
My next thought was food. I didn’t have birch up here, so how was I to feed them? I had read that polyphemus eat wild rose in the Central Valley of California, so I offered them some wild rose from my garden, which they ate right up. They’re doing very well.
I had ordered a UV bug light from a company called Bioquip on July 1st, which arrived up at Tahoe July 6th. That night I set up a white sheet out in the forest with the light — and waited. There were a few small moths that arrived within the first hour, including a sphinx moth that I wasn’t able to identify. Around 22.20, I heard a fluttering in one of the nearby trees, and then saw the shadow of a giant saturniidae – specifically a ceanothus moth — exactly what I was looking for. It landed on the ground near the sheet, which allowed me to catch it. To my delight, it was a female. Females taken at lights nearly always carry viable ova because they don’t fly until they have mated. I caught the moth and put it in a paper bag to lay eggs. That night, it laid no eggs, but the next night, it laid 52. I let her go the night of July 8th to lay eggs in the wild.
The light proved to be the incredibly successful. In a few weeks, I’ll have upwards of 50 ceanothus caterpillars — something I’ve always dreamed of.