Today I spent some time going through the photo backload. A chunk of the photos from this year and last are pictures of various moths that I came across. Many moths (especially in 2010 and early this year) were ones Rowan caught and brought to me, but in the fall I purchased a bug napper from bioquip.com. It’s a uv light with a funnel into an enclosed space at the base, so insects attracted to the light end up caught in it.

We had it going each night from late August into late October at least and saw several different moths that I had not previously noted. We also caught lots and lots of Yellow-underwing Moths (Noctua pronuba). Unfortunately the light seems to have burned out, but I’ll try to get a replacement bulb or two ordered so I can have it going early in the spring. I’m looking forward to seeing how the species change over the seasons.

This moth is probably Ceranemota fasciata, a member of the False Owlet Moth family. I think it was attracted to the bug napper light.

A Northern Thallophaga (Thallophaga hyperborea) was resting on the kitchen window today.

Thallophaga hyperborea observed mid-May 2010.

In May Connor found and brought me this Thallophaga hyperborea which had been crawling up a stake he had pounded in the ground. It seemed a strange place to find a moth, but upon learning its identity (via bugguide.net) and reading a little about the life history, it made more sense.

Larvae of this species dine on conifers, including our local Western Hemlock (Tsuga heterophylla) and Sitka Spruce (Picea sitchensis) then spend the winter as pupa in the soil before emerging as adults in the spring. It seems likely this individual was just emerging when Connor found it.

Thallophaga hyperborea observed mid-May 2010.

Thallophaga hyperborea observed mid-May 2010.

Variable Carpet (Anticlea vasiliata) observed mid-May 2010.

Variable Carpet Moths (Anticlea vasiliata) are aptly named for their diverse array of color morphs. This May I photographed two different ones, to go along with one I photographed April 2009.

Information I’ve seen about larval food plants does not includes only raspberries, which many people raise, but they are not especially common. It is possible this species moved in with the introduction of raspberries, though I suspect they have other food plants that are native – perhaps salmonberries (Rubus spectabilis) which are abundant.

The photo which leads the post represents the least marked end of the spectrum for this species, with those shown below being perhaps more typical. Note the dark lines present in the relatively unmarked individual are also present on the other individuals, though the darker bands obscure them somewhat.

Variable Carpet Moth (Anticlea vasiliata) observed on Hillcrest Drive.

Variable Carpet (Anticlea vasiliata) observed mid-May 2010.

I was a little surprised to find an active caterpillar on the branches of Sitka Alder (Alnus viridis) in February.

While down at Lincoln Street Beach the other day with Connor, I happened to notice this caterpillar crawling around on the branch of a shore-side Sitka Alder (Alnus viridis ssp sinuata). Later I found a couple of others, though I was unable to relocate the first one. They blend in to the branch quite well, so I was lucky to catch the first one moving. After knowing where to look and what to look for, I was able to find the others even when they were not moving.

I was aware that some species of moths and butterflies overwinter as caterpillars, but I have not previously found any here (not that I’ve been looking), nor did I expect there would be ones that are active in exposed locations through the winter. I’m making the assumption that these caterpillars have been active through the winter, as it hasn’t been so warm in recent days that I would expect things to decide winter is over. In any case, it seems likely that these caterpillars have a reasonable tolerance for freezing conditions. I found them on the ends of branches with no cover, so night-time temperatures on cold days would almost certainly get below freezing. I don’t think they could crawl back down the tree fast enough to take shelter in the dirt, but I could be wrong about that, I suppose.

There is some question in my mind about what these are eating. Given where I found them, it seems likely they are eating some combination of bark, buds, or developing catkins on the alders. It also seems possible, though unlikely, that they are just hanging out, but not eating, for the winter waiting for the leaves to emerge in the spring. If this is what they are doing, I see little advantage to being active at all over the winter, in fact, it seems like it would be a big disadvantage due to increased chance of death due to weather or predation. On a bud not too far from one of the caterpillars I found, I did notice a little bit of damage on a leaf bud. It could have been from a caterpillar chewing on it, but I’m not sure whether it was or not.

I was a little surprised to find an active caterpillar on the branches of Sitka Alder (Alnus viridis) in February.

I was a little surprised to find an active caterpillar on the branches of Sitka Alder (Alnus viridis) in February.