Tay Meadows Tidbit – tiny bones

bones4

About a week ago, before we got all that snow (as you can see from the photos), I was hunting for a ball I’d thrown for Raven that had disappeared into the woods and she seemed unable to find. I circled wider and wider, completely puzzled about what happened to the ball (it took a funny bounce, it later turned out, and ended up on the other side of the driveway yards away from where we were looking). Eventually my circles brought me to a track in the forest, barely more than a tree-less gap, that ran between the natural forest and the artificially-planted pines at the foot of the drive.

Out in the middle of this, I spotted some poop. It looked like hawk or owl poop. I remember reading on Julie Zickefoose’s blog some time ago about the difference between hawk and owl poops, in that one (I think owl) drops it straight down from their perch, while the other (hawk) expels it at an angle. The first ends up as a blob on the leaf litter, while the latter results in more of a streak. These ones looked definitely blob-ish, so I suspect owl, and a good-sized one at that given the amount of poop. Perhaps the Great Horned that we’ve heard from time to time and whose pellet Dan found under the maple in the front yard.

bones5

Looking closer, I noticed there was a pile of bones beside the poop. They were completely cleaned off. I couldn’t tell how long they (or the poop) had been there – possibly even since that first pellet was found in early October. Although we tend to think of bird poop washing away quickly, if it had been a dry spell, the poop might have hardened making it harder to wash off the leaves. My suspicion is that these bones used to be in a pellet, but that rain that we’ve had since (and quite a bit of it at times in November) combined with the work of scavenging beetles and other invertebrates, have decomposed and washed away the hair that used to be matted up with it.

I can’t tell what they used to belong to. Most of the bones were broken or fragmented, and the only skull bone I could pick out was a portion of a lower jaw bone, below. I didn’t think owls broke the bones when they were digesting their prey and forming the pellet, and I briefly toyed with the idea that this might be a snake poop, but aside from the broken bones there was nothing else to conclusively support that. I saw a few vertebrae in the pile, but the rest were generic long bones, or at least looked that way. The jaw bone was tiny, and quite long relative to its size. Shrew, perhaps?

bones6

Advertisements

10 responses to “Tay Meadows Tidbit – tiny bones

  1. Nice! Owl pellets are always a fun find – especially when you get full skulls. I got an excellent kangaroo rat skull from one recently.

    Btw – they’re not “poop” though – the owls regurgitate the pellets to get rid of the bones and hair and such that they can’t actually poop out.

    Go back to that spot – owls tend to reuse perches often!

    -Ken

    • My bad – I just enjoyed this again and realized that you didn’t suggest that the pellet was poop. Sorry for the implied ignorance!

      • Thanks, Ken – No worries, I suppose my phrasing was a little confusing. Unfortunately, the site is now buried under several inches of snow, but I’ll have to check the area periodically to see if the owl ever comes back.

  2. You might very well have bones from more than one critter there. The teeth on the jaw certainly look the right type for a shrew, except most shrew teeth are reddish black. The number, however, seem to fit.

    The rest of the bones, on the other hand, look too big to belong to a tiny shrew.

    We use bone sorting charts with the kids here when we dissect owl pellets. They have columns for rodents, shrews, moles, birds, so you can tell what critter(s) your bones belong to.

    If you collect(ed) these bones, I’m sure you can find a chart on-line that will help you ID them. If not, let me know and I’ll mail you one! :)

    • It’s entirely possible, Ellen. I tend to think of owls as eating one animal, then regurgitating the pellet before eating the next, but to be honest, I have completely no idea on their feeding habits.

      I was thinking that regarding the red teeth of shrews, and wondered if the iron/enamel had somehow got dissolved from the teeth in the stomach (which would be pretty acidic). The other possibility is that it’s not one of the red-toothed species of shrew.

      I had no idea there were bone sorting charts for picking apart owl pellets. Indeed, I’m seeing several available online. I didn’t collect these when I found them, but knowing that now, I should go back to get them. Thanks for that tip!

  3. I have found many briken bones in owl pellets. Years ago I spent an entire semester examing owl pellets, and it was the experience of a lifetime.

    Possibly shrew, yes, but would need mor information to confirm.

    Bill:www.wildramblings.com

    • That would be an interesting way to spend a semester! Was it for a research project, Bill? I’ll have to go back down and see if I can collect those bones and sort through them to try to get a bit more info.

  4. That is exceptionally cool. Not for the food animal, of course, but a nice discovery. And how clean they look!

    (I just spent the weekend at a wildlife refuge on the Texas coast and came upon a very large leftover pile of bones, so finding your post while I’m catching up feels all too timely.)

    • I was a bit surprised by the cleanness, too, Jason – I suspect it’s partly a result of them being rained on for several weeks.

      It’s funny how sometimes the timing can be so coincidental with other blogs posting something you’ve just seen. Partly due to the seasonality of nature, but sometimes just random coincidence.

  5. This pellets consist fragments of maxilla and other bones of frog specimen genus Rana.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s