I’ve been raising caterpillars for about 6 years now. I say “caterpillars” instead of “butterflies”, because once they emerge as an adult butterfly, I let them go, and my involvement ends.
The species I get to raise is the Eastern Black Swallowtail. We grow parsley in our garden, and parsley is one of the favorite host plants where swallowtails like to lay their eggs (along with rue, dill, carrots, fennel, and a few others). I found these cute caterpillars munching away on the parsley one day.
We counted an even dozen of them. As the days passed, though, their numbers steadily decreased. Only 2 of them made it to the pupa stage, and one of those pupas got eaten by a wasp. Finally, though, one of the most gorgeous creatures emerged! She was content to rest on my hand while her wings dried out, and after a while flew off.
After that I decided to try to bring the caterpillars indoors to keep them from predators. I kept them supplied with food, and they grew well. A much higher percentage made it to adulthood, but there were some losses along the way. I had such a loss this morning.
I feed them with sprigs of whatever plant their eggs were placed on. To keep the sprigs fresh, I put them in a vase-like bottle. The problem is that sometimes the caterpillars aren’t too careful, and fall into the water and drown. To prevent that, I covered the opening with foil, and placed the stems through a small hole I poked in it.
What I didn’t take into account was that as the caterpillars move around and jostle the sprigs, the foil would tear a little, and in time the little hole I poked in the foil got bigger. The now-stripped stems then fell down into the water, and one of the caterpillars must have been holding onto one of those, and was carried into the water, too. When I got up this morning, I found him submersed.
By now I’ve raised around 100 caterpillars, and have had my share of them die. Some only get so big, and then suddenly die. Some have crawled out of the container I had them in, and if I didn’t find them in time, they would starve to death.
So I’m not sure why this one bothered me so much. I do feel responsible, in that it was my bad design that led to it drowning.
Sorry, little guy – I’ll make sure that I learn from this, and make things better for future caterpillars that come my way.