Eastern Tent Caterpillars

Here's another rabble [1] of Eastern Tent Caterpillars. Few caterpillars are as social as Eastern Tent Caterpillars. They spend their non-feeding time crowded together in the silken "tents" they spin, and leave their tent together to go out to eat about 3 times a day [2], then return together to the tent to rest up and work on their tent [3].

These social caterpillars may be more like family than friends. Late in the preceding spring or early in the preceding summer, their moms laid 200-300 eggs. They'll overwinter in their eggs, hatching the following spring. I suspect that if 2 moms laid their eggs in the same vicinity their kids could hatch and team up on a tent, but there's almost certainly a lot of brothers and sisters squirming around in those tents.

In early spring when it can still be chilly, their tents function as mini-greenhouses, helping to keep the caterpillars warm enough to digest food. When temperatures warm, the caterpillars sometimes need to hang on the outside of the tent to avoid overheating. The tents also provide some protection from predators like birds, who'll presumably get a mouthful of sticky webbing if they try and extract a caterpillar from its tent.

May 3, 2023 at Duke Farms
Photo 278556761, (c) jpviolette, some rights reserved (CC BY-NC)

[1] Most of the collective names for moths/butterflies/caterpillars - especially a flight, flutter, or swarm - apply better to flying lepidopterans. A rabble sounded better for their larval form.

[2] They'll typically go out to eat just before dawn, in the middle of the afternoon, and a little after dark. You could look at this as breakfast, lunch, and dinner respectively.

[3] As the caterpillars grow, they need a bigger tent to live in. If you watch them closely you'll probably notice their tent grows as the caterpillars do.