Southwestern Maine Hunting Report: October 31, 2007

I spent most of this week getting ready for the opening of “deer season”, that is firearm season for white-tailed deer hunting. I’ve been to training sessions, collected all the necessary supplies, learned how to remove the brain stem and lymph nodes to test for Chronic Wasting disease, and visited most of the meat cutters that I will be checking for the next five weeks.

One morning, on my way to introduce myself to a local meat cutter, I spotted a large group of Canada geese in a field, so I stopped to watch them for a few minutes. Off in the distance, on the edge of the field, at the very top of a bright yellow maple tree, I noticed a smallish bird perched. For a few seconds, I think my heart stopped beating; I was hoping that this was a northern shrike. Not that shrikes are rare, Maine Audubon’s bird alert has reports of them throughout the state this week, but I haven’t been able to get my eyes on a shrike for over 2 � years.

As a birder, I am often plagued by what I call “nemesis birds”, birds everyone else is seeing but me, or birds that show up ten minutes before or after I arrive. This is very typical for me, and for the past two years it seems that everyone was seeing shrikes but me. People would tell me, “had a shrike on my ride in today”, “there was a shrike in the field just ten minutes ago”, “my shrike was in its normal spot again this morning”. I have been looking all over a shrike. I am outstanding at finding things that look similar to shrikes, such as mockingbirds, but a shrike, I couldn’t find one to save my life. Even my brother, who never so much as looked at a bird until he had kids, called me last spring, wanting help figuring out a bird they had seen in his suburban Boston backyard. “It was the strangest thing” he said, “it was small and grayish, with a little mask, and I swear Jude, it went after a chickadee, but it wasn’t much bigger than the chickadee?” I cheerfully explained what he saw, and what the bird was doing, but in my head, I have to confess, I was thinking, “figures, my brother and ten year old niece are finding shrikes, but I have yet to see one”.

Needless to say, I was thrilled when I got my spotting scope out and focused on this bird, and sure enough it was an immature northern shrike. As a biologist, and a birder, what has always fascinated me about wildlife is behavior, and northern shrikes exhibit some very unusual behavior, making them one of my favorite birds to watch. Taxonomically, shrikes are passerines; perching birds, songbirds, related to things like warblers, vireos, and thrushes. But behaviorally, they are more closely related to hawks or falcons; they eat mice, moles and small birds, as well as snakes, grasshoppers, beetles and large insects. It’s a little unusual for a songbird without any talons, or real mechanism for tearing flesh to eat meat, but shrikes do, it’s amazing. Like my brother, I too have watched shrikes pursuing small birds through shrubs and tangles, and because they are a songbird and have small wings, they are able to make quick turns and pursue their prey through dense thickets. Small birds often flee into dense cover to avoid a predator, and birds like sharp-shinned or Cooper’s hawks, with their larger, broader wings have to turn off, and give up the chase. This is where the shrike has an advantage; it can follow the chickadee into the densest of thickets.

Without the talons of a raptor, a shrike uses a sharp blow from its powerful beak to stun birds, and can use its beak to cut through the vertebrae of its prey. Shrikes regularly impale their prey on a sharp branch, bit of fencing, or thorn (often while the prey is still alive), thus giving the shrike one of its local names of butcher bird. In fact the Latin name for this bird, Lanius excubitor literally means butcher watchman.

Northern shrikes are about 9 inches with a grayish back and belly, a white throat and black wings and tail. Their wings have a prominent white patch, and outer portion of the tail is also white. Shrikes have a dark mask around the eye, and a strongly hooked bill. They breed in open county with medium or tall trees across Alaska and northern Canada. Shrikes winter from the southern portion of their breeding range southward to the northern United States. Their winter range and abundance is strongly linked to population of small mammals. While foraging, they consistently sit on an exposed perch, or the top of a tree and watch for their prey.

Similar in appearance and habits to a Northern shrike, loggerhead shrikes used to breed here in Maine. Their populations have declined drastically throughout their range, and now are virtually gone from the northeastern part of their range, primarily due to habitat loss. While loggerheads would be in Maine during the breeding months, northern shrikes are generally just here in the non-breeding months. If you happen to find a shrike during the breeding season, between say May-August, please give me a call; any reports of breeding shrikes in Maine are very important.

So, if you see a smallish bird perched on the top of a tree, take a minute and look, this time of year and throughout the winter, it’s possible you’ll see a shrike. Although I couldn’t stay long enough to see this immature shrike pursue a bird or mouse, I was thrilled to finally find one!