As we creep toward spring, roaming flocks of blackbirds may show up at any time.
Red-winged blackbirds are one of the most widespread and successful land bird species on this continent. They range across its entirety, breeding from central Alaska to Newfoundland south throughout the United States. They occur in winter south to Costa Rica in Central America. They are hardy, adaptable and abundant.
They are hard to count at feeders as they rarely stay put for long. Most of these early arriving migrants are continuing further north to breed. While visiting the Cape and Islands during late winter and in the spring they are interested in feeding constantly, attempting to gain and store energy for the final push to more northerly breeding grounds.
Red-winged Blackbirds have been appearing earlier heading north each spring for years. The northbound migrants currently showing up are 10 days earlier than just a decade ago further evidence of a warming planet. They have just started turning up at feeders around the area.
With small numbers of these birds spending the winter, it is hard, if not impossible, to know if a few birds are new arrivals or over winterers changing their behavior patterns and daily schedules. However, when flocks of Red-wings, virtually all males, arrive, it becomes clear that these are migrants. The male birds move north a week or so earlier than females. They want to be first stake a claim, by singing loud and often, to the best breeding habitats.
The danger with “pushing the envelope” to be first on the breeding grounds is that there may be no food and nasty weather upon arrival. Obviously to be successful as breeders they must survive. As the red-wings currently visiting the Cape and Islands in mid-February are finding, moving north in late winter is fraught with hazards like snowstorms, Nor’easters and bitter cold. When and if the weather improves and southwest winds prevail, there will be many more of these birds arriving with many remaining to breed.
This is an excerpt of the Weekly Bird Report. The full essay is posted as audio below - give it a listen.