I recently was gifted owl pellets by Ben Caruthers. The dried undigested regurgitated remnants of an owl meal is an exciting exploration for a 5th grade WOLF student. I stored them in paper egg cartons inside a ziplock bag in the dining room. I have a very tolerant wife.
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| Exuviae of emerged moths - notice the wing features below |
When I opened them a month later I could see exuviae, empty pupa cases with remnants where there had been wings developing. Among the collection of digested rodent bones, some of the debris was moving. After filming it, (a historic term for video), I extracted a wiggling piece of debris and captured a case-bearing larva attempting to escape as seen in this video.
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| 6 mm moth in owl pellets |
A week later I had an answer. I found several of these 6 mm long moths in the bag. a quick Google search of "case-bearing moths" returned lots of links pointing to clothes/carpet moths in the Tineidae family. The majority of these feed on fungi, lichens, and detritus, which fits with the material in these pellet remnants.
This is most likely the case bearing clothing moth, Tinea pellionella. They are distributed world wide and are frequently associated with human populations. There are a few other similar species in the family that can only be identified by examining their genitalia so we won't go into that.
"T. pellionella larva eats mainly fibrous keratin, such as hairs and feathers. It can become a pest when it feeds on carpets, furs, upholstery, and woolen fabrics. It also consumes detritus, cobwebs, and bird nests." -Wikipedia
The larva lives inside a snug case it constructs from debris such as fibers and hairs. It extends its body to crawl around, hauling its home for protection. Incredibly, it can turn around in the case
to protrude its head and legs at either end and drag the case in either
direction. Finally they will form a pupa and eventually crawl out and expand their wings.
So back to the other question, what are owl pellets and why would a grown man collect them? Owls often swallow mice, voles, small birds, and other prey whole. After its gizzard has sorted out the indigestible parts such as fur, feathers, teeth and bones, the owl regurgitates them in a oval owl pellet. This frequently occurs in a roost where they collect on the ground underneath. Taking these to the 5th grade WOLF School, we students young and old, will examine them to try to determine what the owl had been eating.
There are lots of resources available to students of all ages. This brings out your inner 5th grader without having to get on a bus every morning.
