The great thing about winter owls is that in a good year they can be easily spotted. Unfortunately, this hasn’t been a particularly good year.
Once they come out of the boreal forest in the late fall, Great Gray Owls, Snowy Owls and Hawk Owls pretty much stay put wherever they settle for the winter. And they are diurnal – they hunt during daylight hours. So, if you get a report from someone that there’s a winter owl at a certain spot, you can bet that it’ll probably be there or nearby.
The number of Great Gray Owl reports near Winnipeg this winter is not very high, relative to previous years; I’ve heard that they’ve been seen, but I haven’t been able to get out to tick them off my winter list.
According to Dr. Jim Duncan, wildlife biologist and owl expert, low numbers of Great Grays in the past have coincided with years with thicker snow cover (>180 cm). That’s been the case this winter. Thick snow cover reduces the number of predators that ordinarily feast on meadow voles, their main prey. With their unmatchable sense of hearing, Great Grays have no problem detecting small mammals even under a thick blanket of snow. So, fat healthy (radio-marked) Great Grays are staying back in the boreal forest.
In my neck of the woods Snowy Owl numbers are low this winter as well. But if you check the electric transmission poles and fence posts on major routes in and out of the city, you can almost be assured of finding a couple. We’re nowhere near the record year of 2001 when one party counted 55 Snowies in one day southwest of Winnipeg. It used to be thought that these tundra natives irrupted when the lemming populations of the north plummeted. That simple theory has since been disputed, though there’s some indication that crashes in lemming numbers can account for early arrivals.
Hawk Owls are more easily found this year. They’re not as widespread as they were in 1996-97 when more than 50 were spotted and even I counted a couple of dozen on one outing. And few have ventured into my suburban neighborhood as one did a couple of years ago. I saw that bird every day on my way to and from work usually sitting on the bent-over top of a small spruce tree. Their long tails, big yellow eyes, and non-erect posture make them easy to identify.
Jim Duncan believes that Hawk Owls have clearly had a good breeding season somewhere within a 1,000 mile radius (their normal yearly range) of Winnipeg. That may account for their numbers. All the Hawk Owls he’s encountered thus far have Hatch Year 2010 birds, and they are in excellent condition. One Hawk Owl weighed a whopping 435 grams, possibly the heaviest he’s caught to date. So, they’re not coming here because they’re hungry.