Excerpts from Jim Conrad's
from the August 9, 2009 Newsletter, issued from the Siskiyou Mountains west of Grants Pass, Oregon:
There's a whole group of butterflies known as "the Whites," because they're mostly white, usually with only a little dark or dingy marking. The most commonly known white is the Cabbage White, introduced from Europe, often seen fluttering above garden cabbage plants. However, plenty of other much rarer and more interesting Whites can be looked for.
For instance, suddenly this week a White species has begun showing up here. One trapped in a spider web by the tips of both of his down-bent wings is shown above.
That tragic, pretty little creature is the Pine White, NEOPHASIA MENAPIA, fairly generally distributed in piney regions of western North America. Its caterpillars eat the needles of various conifers, especially pines, which is a little unusual for a White. Genetically the Pine White lies somewhat apart from other whites in our area because it's most closely related to tropical species who feed on mistletoes. There's conjecture that Pine Whites "got into pines" by having ancestors who fed on a mistletoe species parasitizing pine trees.
Pine Whites also "lek," which means that the males concentrate in a small area -- the upper regions of pine trees in this case -- in order to collectively display to females. Females tend to mate with the strongest, flashiest, sexiest, etc., in the group, with the consequence that usually only a handful of males pass on their genes.
Pine Whites also sometimes undergo snowstorm-like population explosions. On my hike this week I saw hundreds of them, but nothing like that.