Speaking of Nature: A long search bears fruit

  • Bill Danielson discovered these bones, which he suspects came from a shrew, within an owl pellet. For the Recorder/Bill Danielson

  • The copper stains on the tips of all the teeth suggest that they belonged to a short-tailed shrew. For the Recorder/Bill Danielson

  • Bill Danielson discovered this owl pellet behind his home. For the Recorder/Bill Danielson


For the Recorder
Monday, May 07, 2018

It was a warm, sunny weekend when Earth Day rolled around, and my beautiful wife, Susan, suggested that we take a walk to celebrate. Our “mission” was to walk the limits of our property to assess the general state of affairs. We were both particularly interested to see the “Back 40,” which is what we call that portion of our spread that is not visible from the house because it is so far in the woods down to the south.

I was concerned that the ground was going to be very muddy, but as we walked along, it turned out to be damp in a couple places, but fairly firm for most of our walk. Again and again, we encountered evidence of the nor’easters that visited us in March. The white pines seemed especially hard hit and their limbs lay strewn across the forest floor where the heavy snow had brought them down.

Eventually, we found ourselves at the south fence line that serves as the only evidence of the property line. At this point, the fence only consists of a few rusted strands of barbed wire that have been enveloped by the trees that the wire had been nailed to. It is down there that the only hemlock trees in my yard can be found and as Susan looked up at their grandeur, I looked down at the ground.

I was searching for an owl pellet. Every time I visit this part of the forest, I take a sweep of the area in hopes of spotting a little lump of graphite gray fur that was once a small mammal. I’d been searching in vain for what feels like years, but on this day, my hopes were running high. There was a generous whitewash of owl droppings on the leaf litter and eventually (perhaps due to the magic of Earth Day, or perhaps because of the presence of my lucky charm), I finally found one. Susan was partially disgusted by the little gift I brought to her, and completely horrified when I slipped it into my pocket.

I brought my treasure back to the house and placed it on my writing desk where it remained for more than a week. Every time Susan passed the desk, I heard a little whimper and occasionally a faint, “Eww” was added for good measure. In my defense, I had completely intended to deal with the issue immediately, but then I caught sight of that flicker from last week’s column and I got distracted. So, I finally got to my project this morning.

The owl pellet was quite compact when I picked it up, but the trip back to the house in my pocket had jostled it enough so that it was starting to come apart. I placed the pellet on some black construction paper (for contrast) and took a photo before I started the process of taking it all apart. I thought I caught sight of a snout and was interested to see what the animal might be.

There are three species of owls that live in my neighborhood and they all eat small mammals. The choices are limited to mice, voles, shrews and the odd squirrel here and there. Mice and voles would be difficult for me to identify, but the teeth would give it away if it was a shrew. Here was a leg bone, there was a rib. Here was a hipbone, there was a vertebrae. Finally, I uncovered enough of the skull to make an identification.

Not only did the maxilla bones still have the front teeth intact, but when I flipped the skull over for a ventral view, I discovered that both mandibles were still in their proper orientation. They came loose when I removed all the fur, but I had both of them. The back of the skull (the parietal bones) hadn’t survived intact, but little flakes of bone that I found could probably have been reassembled into the skull if I had been interested enough to do it.

With the jaws at my disposal, it was easy to identify the little creature as a shrew because of the shape of the teeth. Odds were that it had been a short-tailed shrew (Blarina brevicauda) because of the copper-colored stains on the tips of all of the teeth. I decided to lay out the larger bones in an artistic pattern rather than to try to re-articulate the skeleton. When Susan visited me to deliver a warm mug of coffee, I was amazed by her reaction to my little project. Instead of cringing in disgust, she actually went in for a closer look. She’s just full of surprises.

It may come as a surprise to hear that this is the height of the breeding season for owls. All of the eggs have hatched and the owlets are growing quickly. The parents of these voracious chicks will be working at full speed to keep everyone fed, and the numbers of owl pellets are only going to increase as the month progresses. If you want to find an owl pellet of your own, I’d go out soon. In no time at all, the black flies will be out and that is often enough to chase us all back inside for a while. Good luck!

Bill Danielson has been a professional writer and nature photographer for 20 years. He has worked for the National Park Service, the U.S. Forest Service and Massachusetts State Parks, and currently teaches high school biology and physics. Visit www.speakingofnature.com for more information, or go to Speaking of Nature on Facebook.