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Female moth, recently emerged from underground pupation. The tip of her abdomen is still down in the hole she emerged from. In the photos, a few grains of sand are visible on the moth, and a cluster of sand grains is stuck to the stout spines on one foreleg. This group of moths ecloses underground but the wings remain unexpanded. They then burrow up to the surface, where they expand the wings.

I wanted to return at dusk to watch her use pheromones to call in males, but I had a prior commitment. I returned at 9pm and she had left. I excavated the burrow to determine pupation depth in the soil. Pupal case was 15 cm (6 in.) deep, angled back toward the hill slightly. The opening of the hole at the ground surface was about 1 cm in diameter. Looking down into the hole, it was open for about 2cm and then filled in with loose dirt below that.

Upon excavation, I wasn't able to find a pupation chamber, just parts of the pupal case in the dirt (see photo with found pieces posed on a rock). Location is on a steep south-facing slope. Soil is decomposed granite. Photo credit: NPS/Paul G. Johnson.

Was visually following this Yellow Warbler when it landed on an open branch next to a much larger bird. To my surprise, the adult warbler began feeding the large fledgling Brown-headed Cowbird. A very graphic illustration of the Cowbird's practice of laying its eggs in the nests of other birds. Even much smaller birds, like this Yellow Warbler. Unfortunately, the warbler's own young tend not to survive.

The larger bird in this photo is a fledgling Brown-headed Cowbird, being fed by a tiny Yellow Warbler after being hatched in the warbler's nest. The Cowbirds have a parasitic practice of laying their eggs in the nests of other birds. As a result, the young of the unsuspecting host bird tend not to survive. I suspect in this case, it also puts a great deal of stress on the adult birds, as they attempt to feed this huge chick.