The male Eastern Tiger Swallowtail butterfly (pictured) is yellow with four “tiger stripes” on each of its forewings. The female can be yellow or black, and has more blue on the hind wings than the male. Eastern Tiger Swallowtails are currently mating and laying eggs on plants which their larvae eat, which include black cherry, red maple and American hornbeam. When the caterpillars first hatch, they resemble bird droppings – an effective way of decreasing predation. As they get older, the larvae turn green and have a large head and bright eyespots.
With the warm temperatures this week, mourning cloak butterflies have been seen gliding through the leafless woods. Like eastern commas, question marks and red admirals, mourning cloaks overwinter as adults. They resemble dead leaves so much that from a distance the entire insect seems to disappear. Up close you can see the velvety texture of the wing scales, said to resemble the clothing mourners used to wear; hence, their common name. Mourning cloaks live up to ten months — an impressive life span for a butterfly. As they age, the yellow border of their wings fades to an off-white.
The striped caterpillar that is crawling along the surface of fresh snow is the larval stage of a noctuid or owlet moth (species unknown). Noctuids are dull-colored, medium-sized, nocturnal moths that are attracted to lights in the summer. They usually possess a well-developed proboscis (mouthpart) for sucking nectar. You may be familiar with the common garden pests, cutworms, which are also noctuid larvae. How this larva survives freezing temperatures I do not know, but I have seen several dozen at a time crawling around on top of the snow. Note: Jean Harrison, a fellow nature lover, just identified this larva as Noctua pronuba, a winter cutworm also known as the greater yellow underwing (moth), a recent immigrant from Europe.