Saturday, November 19, 2011

Canada Geese

Thousands of Canada Geese have been flying overhead every evening for the past few weeks. They eat their dinner in the fields of the experimental farm and then go roost along the Ottawa river. This migration is an incredible sight and I am always amazed how much we ignore it. Sometimes along Hunt Club road, wave after wave of geese in their thousands can be seen flying over in just a couple of minutes and no one bats an eye. This didn't happen 30 years ago when I was young. You just didn't see the geese hanging out in the fields around Ottawa. There also weren't any resident Canada geese in the parks and beeches back then. This recovery in the numbers of geese has been incredible. According to the Ottawa Duck Club they helped introduce Canada geese back to the Ottawa area by bringing some from the Morrisburg bird sanctuary to the Shirley's Bay reserve in the 70s. Presumably this was a resident flock that then went on to stay and multiply in the area.

According to the net the sub species of Canada Geese that tends to be resident year round in the south is the Giant Canada Goose. It was thought to be extinct in the late 50s but a small population was discovered that was then bred and used to repopulate the resident sub-species. Canada geese, I've learned, are highly variable in size with several sub-species. The sub-species are hard to tell apart but in general they are geographically based with different subspecies having different breeding grounds that they fly to year after year. The resident populations we have now that are undergoing a population explosion may not be the Giant Canada Goose but may instead be a mixed breed that was intentionally released after having been in captivity. Since the migratory path is passed down through the generations from parents to offspring as they lead their charges along the migration, the birds bred in captivity would have lost that history. The migratory sub-species we mainly have here in Ottawa would be the Atlantic sub-species that makes a round trip from Ungava in Northern Quebec down to the eastern seaboard around the Chesapeake Bay area. The Atlantic Canada Goose is also quite a large goose. Those that breed even further north and to the west can be even smaller.

No comments:

Post a Comment