Nature Notes for December 9, 2011
Just when local birders were despairing about the dearth of interesting or unusual birds in the area, some turned up. In the last week of November, at least five Snowy Owls were reported from Presqu’ile. These were quickly followed by reports from Port Hope harbour, Cobourg harbour and Wicklow beach.
The Ontario Field Ornithologists’ listserv is reporting Snowies from all over southern Ontario.
On December 6, there was a large, dark Snowy Owl on the end of the west jetty on the Port Hope lakefront. The previous Sunday, there was a different one - much smaller and whiter - on the roof of a building just east of the Port Hope water treatment plant.
As with most raptors, female Snowy Owls are larger than males. As well, females are streaked with many dark bars. Adult males are completely white, although young males may have some faint barring.
When there is snow on the ground, these birds can be very difficult to see. Sometimes they look like a large lump of dirty snow. It’s not until they turn their heads to show their yellow eyes that they are recognized as a bird.
The white coloration is very good camouflage for a bird that nests in the Arctic tundra.
Their primary prey in the Arctic is lemmings. When the lemming population plummets, which it does on about a 4 year cycle, the owls are forced to leave the north in search of food. That’s when they turn up in our area.
In southern Ontario, there are no lemmings, so the owls switch to other food: mice, voles, rats, rabbits, smaller birds – essentially anything they can catch.
The breeding grounds are far enough north that, in summer, there is almost 24 hours of daylight. Therefore, it is not unusual to see these owls active during the day. If they winter in the Arctic, they also spend part of the year when they have to be active in darkness.
This species is one of many Arctic nesting birds that have a circumpolar range. That is, they occur in the north of Europe and Asia as well as North America.
Locally, they are often found along the waterfront. Perhaps those open, windy sites look to the birds like the tundra. They can be found in any open site and are often found in agricultural fields. They have also been found perched on utility poles, fence posts, barns and silos. In town, I’ve seen them perched on top of buildings. Several years ago, on the last irruption of Snowy Owls, I found one sheltering alongside the air conditioning unit atop the condos at Cobourg harbour. A number of years ago, I awoke to one perched on the chimney of the house of my back fence neighbour.
To date, this seems to be a good year for Snowy Owls in the south. It’s worth really looking at that lump of snow. It might turn out to be one of the visiting owls.
The annual Christmas Bird Counts will be held before the next column appears. Port Hope-Cobourg’s count is on Saturday, December 17 and Presqu’ile-Brighton’s on Sunday, December 18.