On the same day that I found the pile of feathers at the Perth Wildlife Refuge, my mom and I also came across another surprising discovery. Caught in a pawprint in the snow, at the edge of the path where it crossed through an open field section, was a caterpillar. It was a moderately warm day, by winter standards, about 6°C (43°F), but even still – a caterpillar? What was it thinking? No matter how nice and warm that sun felt on its back, surely the snow must have felt cold under its tiny tootsies. By the time we happened across it it was late in the afternoon and the sun was sinking, no longer providing the sort of warmth it would have at midday. The caterpillar was sluggish, but still alive. I took a few photos of it on my palm, where perhaps the heat of my hand helped to revive it a little. Then I found a clump of grass under a branch that seemed fairly protected and tucked the caterpillar in there.
The fuzziness of it means it’s most likely in the tiger moth family, Arctiidae, and I assumed that the individual tufts along the back suggested tussock moth (of the Tribe Phaegopterini). I browsed through BugGuide’s Phaegopterini pages, but didn’t see anything that was a perfect match. The closest was Silver-spotted Tiger Moth, I think. I submitted it to the ID request pages to get a confirmation or a correction on ID. Turned out that I was right on the family, but wrong on the tribe. The caterpillar was identified for me as likely a Virginia Ctenucha, Ctenucha virginica, which is in the Tribe Ctenuchini. Virginia Ctenuchas are a meadow species, with the caterpillar feeding on grasses, sedges, etc. The caterpillars overwinter at the ground surface, underneath leaf litter or matted-down grass. Perhaps this one had been near a rock or some object that had warmed substantially more than the surrounding ground, melting enough of a hole to expose the grasses and warm the spot where it was hiding.