The warm March weather may have moved annual seasonal activities ahead of schedule by a week or two. It’s possible that insects are hatching sooner and that birds may begin to migrate back a week or two earlier than usual.
Not all birds will migrate back, but those who have staged relatively far north in the winter may be among the first back. In an interview with the Detroit Free Press, Post-Doctoral Fellow at the Cornell Lab of Ornithology in New York Frank La Sorte said the return of birds to their summer homes “depends where the birds are staging from. Birds that winter well within the tropics don’t know what’s happening in the northern United States.”
Birds that do encounter a colder-than-comfortable environment upon return may actually end up flying back south. Their high metabolism allows for that to occur, although flying is very demanding and so they will need to eat every couple of hours to cover ground quickly and efficiently.
Birders nowadays may see animals they haven’t seen before in that area some 20 years ago. La Sorte mentioned a study of 59 bird species and how they react to climate change. The study concluded that it takes about 35 years for birds to move northward to colonize places that are similar in climate to the ones they used to live in before.
For example, a black vulture now lives in places in Massachusetts where the climate in 2012 is similar to what the temperature and climate were like in 1980 some 200 miles farther south, meaning that it’s getting warmer than it was 30 years ago and attracting birds further north than where they normally dwell.
Photo: Andrea Westmoreland