This winter is for the birds — or more specifically, for birds of prey. I’ve seen a greater variety of raptors during the last few weeks than I did all summer.
Many raptors are over-wintering here, and there have been numerous sightings of red-tailed hawks, sharp-shinned hawks, and Cooper’s hawks. In addition, there are also exciting visitors from the far North; one such bird is the northern hawk owl.
This beautiful, medium-sized owl breeds throughout the boreal forests of Canada and Alaska. As is the case with other northern owls — the snowy owl and the great grey owl, for example — the hawk owl resides in its breeding range year-round. Doing so requires it to be as proficient at hunting in broad daylight as it is in dark-est night, as far northern climes experience almost continuous daylight during the summer months.
When hawk owl populations thrive and their prey populations crash, these owls will “irrupt” from their normal range and invade areas of southern Canada and the northern United States. Usually, this may include northern Maine, if at all (and in fact one was reported in Stockholm a few weeks ago); so it has been a delightful surprise for birders to have one show up along the coast, in Bristol.
The owl has been there for a few weeks now and has staked out a good hunting spot that unfortunately happens to be near a well-traveled road. Observers have witnessed it hunting and catching mice and possibly other small mammals.
These tough northern owls don’t restrict their diet to mice, voles and shrews. They have also been known to prey upon rabbits, hares, weasels and other birds such as woodpeckers, doves and even grouse and partridge. Regarding the latter, this owl has displayed boldness and cunning in certain situations, having been known to “streak in and speed away with snipe or woodcock that have been downed by hunters,” according to author A.W. Eckert, in “The Owls of North America.”
Hawk owls have also been observed following farmers and forest workers, snatching up small mammals disturbed by their passing, as reported by author A.C. Bent.
Always opportunists, these owls will eat carrion, as well as dead prey put out by humans. If they don’t immediately consume their food, they’ll cache it in crevices, old woodpecker excavations, or in the snow at the base of a tree, according to the “Birds of North America” species account.
This owl is also cosmopolitan in its hunting behavior. As reported in the BNA, it can hunt by hovering, then suddenly plunging down — often through snow — to catch its prey. It has been observed to stalk prey on the ground and will run through the snow after a lemming. It will also catch avian prey in flight and is adept at maneuvering through heavy cover while in pursuit. In this, it is similar to our Accipiter hawks — the sharp-shinned, Cooper’s, and goshawk — which are all specialized in hunting other birds on the wing. Physical adaptations such as short, rounded wings and long tails make this precise maneuverability possible and are exhibited in the hawks as well as the hawk owl — hence its name.
Often, northern owls such as this hawk owl arrive here in winter because their prey populations farther north have crashed. This means the birds may be food-stressed and in some cases literally starving to death.
There are guidelines that should always be followed in situations such as this. Consideration for the bird in question should always come first and foremost. Is the number of observers interfering with its ability to hunt? Are observers too intent on getting the ultimate photograph or close-up view at the expense of the bird itself? These are questions that should be considered carefully by anyone privileged to be there.
In addition, respect for nearby landowners’ property and privacy should always be practiced. A few people might not have much of an impact, but larger crowds almost certainly will; such events have turned into a veritable circus in the past.
I have not had the privilege of seeing the owl in Bristol. Hopefully, the bird will remain for a while longer in this location and I will yet have this opportunity.