It looks like I’m not the only one these days experiencing an abundance of monarch butterfly caterpillars. Every day it seems someone else posts something about these “cats” on the newsfeeds I look at on Facebook.
I just started noticing monarch caterpillars in my own yard about three weeks ago, after watching monarch butterflies flitting around my yard. Although I got busy with other things and failed to check for eggs, a short while later I noticed that my eight or so lush, fully leafed milkweed plants were showing places where the leaves had been chewed. And then it took no big feat of detective work to find the yellow-, black-, and white-striped caterpillars happily crunching on the greenery. All of my milkweeds had caterpillars of varying sizes. Some plants had as many as six caterpillars all working on the foliage.
The milkweed plants have now become leafless stems and the caterpillars have disappeared.
Like I’ve done before without success, I scanned the eaves of the deck and the branches of nearby shrubs and trees looking for the green chrysalises that mark the next stage in a caterpillar’s life change. But again, no luck at finding them. Although these chrysalises are vivid green with a golden halo of spots in a crown on top, they blend in very nicely with the green leaves. Maybe the ever-present anoles ate some of them. I just hope some are still around and that one day I will be rewarded once more by the sight of mature monarch butterflies flitting around my yard, laying eggs again on the milkweed plants when their leaves grow back.
A few years ago, I took a more proactive approach at raising caterpillars. I brought some in the house and maintained them in a tub. Milkweed leaves were provided and a netted top over the tub confined them when they crawled up to find a place to hang and turn into a chrysalis. But this was not a very successful project for me. I started with five, plump caterpillars. One drowned in a pan of water and three succumbed to “black death,” a viral disease that caused the caterpillars to turn black and liquefy. Only one caterpillar made it to the chrysalis stage and on to a butterfly. The deterioration of my “cats” was horrible to watch, and I never attempted this indoor experiment again, but many people do and have better luck (or more sterile surroundings or drier air, or something that I lacked).
One friend, Betty Duck-worth, has reported almost
daily on the growth of the caterpillars she has been feeding and watching in a caterpillar-rearing container that she bought online. She has been very successful, with a number of adult butterflies produced. She’s only mentioned one disease, called anal prolapse, which sounds about as bad as black death to me.
Another friend, Sandra Baker-Hinton, has been raising monarch butterflies for years, but even she says there are more monarch caterpillars around now than she has ever noticed before.
The problem for those who try to raise butterflies is tending to their voracious appetites. It gets expensive rushing off to Liberty Landscapes, just over the bridge, to buy more milkweed plants. Word has it that monarch caterpillars will also eat butternut squash, and I’m wondering who was first to try that unlikely food source.
As for me, I’m still looking for chrysalises in my backyard and wishing for adult monarchs someday soon. And, not long afterward, I should also see swallowtail butterfly “cats” on the parsley and dill plants that I provide more for them than I do for the culinary value.
Ever since my failed indoor butterfly growing project, I am now content to watch the insect action that is visible in my yard without having to be face-to-face with anal prolapse or black death. This may still be happening, but at least I don’t have to watch.
Pat Foster-Turley is a zoologist on Amelia Island. She welcomes your nature questions and observations.