Saturday, July 9, 2011

Tracking Quiz: Skull

Janet writes: Upon our arrival at my in-laws house in Maine last
weekend, my mother-in-law sent me out to a piece of property with
instructions to find "something rare" to stop development. She recalled
playing there among lady slippers and other less than ubiquitous
wildflowers, as a child. There were indeed some interesting
wildflowers, though none of them rare.

The skull in the above photo was on the forest floor at the base of a
cliff. I noticed the gleaming white brain case from a distance, and
thought it was some kind of mushroom. I'm glad I went over to confirm.

With delicate bones still intact, it may be a rare find, but the species
is not rare. Can you identify it?


  1. Does that thing really measure 9 inches?! A very large bald eagle?

  2. 9 inches? No. We might need to be on a different continent for that, or perhaps in the Jurassic period. Those are centimeters, Susan. Wendy, good guess, since bald eagles are commonly seen near my in-laws' beautiful home on the coast of Maine.

    This really isn't that hard. Look at the overall shape and maybe google images to confirm your guess.

  3. Ahhh ... centimeters! That's a game changer. I'm leaving the Jerassic period behind now. Osprey?

  4. I'm thinking owl, maybe Great Horned owl? It's pretty!

  5. I agree with Marie that it is an owl skull. Size suggests either great horned or barred owl, according to the books and online sources I consulted. I'm sure there are people who can tell one from the other at a glance, from the shape of some tiny bone or aperture, or something like that, but one consistent difference appeared to me to be the slope of the forehead. Great horned owl skulls seem to have a slightly steeper forehead. I thought this skull better matched that of a barred owl, but great horned could well be correct.

    The most noticeable difference between skulls of owls and skulls of the other species suggested above, is the short, squat shape of the former. That is, the width of an owl skull relative to the length (from tip of bill to back of skull) is noticeably larger.

    Turkey vulture was a good guess based on my report that the skull was at the base of a cliff (they often nest amongst nooks and crannies of cliffs and boulders), and osprey and bald eagle were good guesses since the location was near the coast of Maine. But turkey vulture skulls are much narrower, as you might expect if you've seen the shape of a TV's featherless head. Bald eagle skulls are a little more squat, but larger than this skull. Osprey skulls are about as squat as bald eagle skulls, and smaller than the skull in these photos.

    Here is a good online site for skulls: