Raptors usually start to return to Manitoba in February and continue to arrive in waves right through April. I was in Ecuador for much of this period; so, when I returned I couldn’t wait to get out and enjoy the show. When a clear, sunny day with south winds arrived, I dropped everything and headed for the St. Adolphe Bridge. At this site south of Winnipeg I can often see as many as a thousand or more hawks and eagles on a good day. This day was almost a complete bust. Six Bald Eagles, a Cooper’s Hawk, and a couple of Sharpies and Kestrels. Big whoop!
This, I discovered, was not unusual. The entire 2012 raptor migration season has been a bust in Manitoba. Far fewer Red-tailed Hawks, for instance, have passed over the St. Adolphe Bridge than ever before. At Windygates, in the Pembina River valley south of Morden and near the American border, the situation is more carefully monitored. Rigorous daily tallies from February through April indicate that 9,000 fewer raptors passed the observation points this year than in 2011.
These diminished figures have led to all sorts of speculation.
An unusually mild winter, with almost no snow accumulation, and an early onset of spring probably minimized the thermals that raptors rely on. Perhaps higher winds blew much of the straw and chaff off farm fields, resulting in fewer places for rodents to hide and a dearth of the usual stopover, refueling points for the raptors. Drought in the southern US, especially Texas, could also have affected migration.
Whatever the causes, our raptors may have been hit by a triple whammy — displaced on their wintering grounds, contending with troublesome weather systems on their routes north, and spread out because of the lack of snow cover here, they may have altered their migratory routes or patterns or styles. They may be here and gone, having used non-traditional ways of getting into the province and farther north.
Or they may not be here yet. Or their numbers may have been dramatically reduced.
Only time will tell. What’s happened to the raptors in your area?