Photo by Barry Wallace
John McCracken has written a revealing article in the fall 2016 edition of BIRD WATCH Canada, part of which I thought I would pass along in this space.
"Breeding Bird Survey results show that Ruby-throated Hummingbird populations across North America have increased by about 2.3% per year since 1966. Long Point Bird Observatory's migration montitoringprogram shows a similar pattern, with average annual increases coming in a 5.7% in spring migration and 7.4% in fall. Second-generation breeding bird atlas projects in Ontario, Quebec and the Maritimes show noteworthy expansions in hummingbird distributions. Population increase are thought to be in response to the ever-growing popularity of hummingbird feeders and backyard flower gardens, perhaps combined with the warming effects of climate change".