Pellet Puzzle: What’s On Owl’s Menu?

I love it when owls throw up on me.

One winter day when I was walking my dogs in a thickly wooded area, I sat down for a rest on a fallen log. As the dogs sniffed their way around the area, something fell from the sky and dropped into the snow at my feet. I looked up, and discovered I had chosen a seat right underneath a great-horned owl, who had just gifted me with a fresh owl pellet. I carefully dug that pellet out of the snow and carried it home like it was worth a king’s ransom.

A camping weekend at a prairie reservoir produced another owl gift. Sitting around an evening campfire, something hit the ground in front of me. I looked up into the spruce tree to spy a tiny saw-whet owl sitting there, looking down at me.

So why do I like it when owls give me pellets?

Owls, like other birds-of-prey, eat their food whole. They use their beaks to rip their prey apart and then swallow large chunks. The digestion process separates the softer materials (such as meat) from the harder material (such as bones). These indigestible bits are then regurgitated in the form of a small, sausage-shaped pellet.

Great-horned owl pellet

Pellets contain things like the bones of birds, mammals and fish, teeth, claws and beaks, insect head parts and wing cases, seed husks etc. These are usually enclosed by softer material like fur, feathers and vegetable fiber.

Careful dissection of owl pellets will tell you what that owl has eaten.  It’s like a mini-archaeology dig spread out on a table – a puzzle to be solved.  Has this owl been eating the cute little chipmunks around the cabin? Or has he been dining on something larger? Over the years I have found numerous feathers, bones and even cat claws in owl pellets. (yes, large owls will take a domestic cat – another good reason to keep your felines indoors).

In spite of the fact that great-horned owls are very common in our province (they are our provincial bird), anyone that knows of a nesting sight generally tends to guard the information like it’s a vital military secret.  Hoops must be jumped through before the information is shared.

Apparently having passed the trustworthy test, a friend with a river-side cottage showed me his carefully gathered great-horned owl pellets last month. Multiple owl pellets!! I was in heaven, envisioning untold quiet hours of pellet dissection. He quickly brought me down to earth by saying he used them to teach children about owls. Oh. But he did allow me to have one.

I should point out that the rodent body parts in owl pellets may contain viruses and bacteria, so it’s advisable to sterilize the pellet in a microwave before dissecting.  Having done that, I happily buckled down to dissecting my (one) precious owl pellet. Here are the results:

I am not a biologist, so although I thought these were the jaw & spinal bones of a small rodent, I couldn’t tell what the animal was.  Then I had a brainwave.

I took a picture of the bones discovered in the pellet and posted it on my twitter account. Within minutes I had four replies telling me they looked like ground squirrel parts. As Richardson’s ground squirrels are very prevalent in the area, this made a lot of sense. This identification was later confirmed by a biologist who examined the actual bones.

There are numerous places online where you can buy sterilized owl pellets which come with complete instructions. Taking the time to dissect them with your children is a great way to teach them about  the balance of nature. Plus, the fact that the owl threw it up (eeuws all around) gets their attention in a big way.

So this winter, when the temperatures drop and the ground is covered with snow, gather the kids around the table and poke through a few pellets. It’s something they will always remember. And if you have extra pellets, feel free to give me a call.