Fall Webworm caterpillars have been everywhere. This one was on a raised bed on the sidewalk next to the local high school last week, with barely a tree in sight.
I don’t even remember where this was, back in July.
Here’s yet another, along the 5th Avenue Green-Wood fence. Uh-oh!
You see, everybody knows the prolific caterpillars are out and about. Dozens of parasite species attack Fall Webworm, which provide a lot of meat. This one is an ichneumon wasp. I’m not sure what her strategy is because I can’t get her down to species level. She’s a member of the tribe Gravenhorstiini of the family Ichneumonidae.
But that strategy ain’t good, at least according to the caterpillars. The wasp, of course, has another agenda.
Those are, in fact, caterpillar droppings. These colonies are messy.
Here’s more. These are cocoons of a Meteorus genus wasp. They hang from rather crinkly silk under the webworm nests. Both look like they have exit holes at the base. According to Eisemen and Charney, if the exit whole is irregular and on the side, it’s the work of another wasp who parasitizes the parasite.
Webworm Days
Published September 12, 2019 Fieldnotes 1 CommentTags: Brooklyn, caterpillars, Green-Wood, insects, wasps
Geez, red in tooth and claw!