By Beth Daley, Globe Staff'
Birders are reporting mind-boggling numbers of robins - often seen as a symbol of spring - this winter but it’s not likely we’ll be experiencing warm weather anytime soon.
Birders are reporting record numbers of robins this year (Mark Wilson, Globe photo)
Massachusetts Audubon ornithologist Wayne Petersen says one Barnstable roost reportedly contains up to 80,000 birds and another in Hanson “included no fewer than 25,000 and arguably 50,000 robins in mid-December.” And there are undoubtedly many other roosts out there no one has reported, he notes.
What gives with these Hitchcock-like numbers?
First, populations of robins, unlike a number of other migratory birds, are actually increasing in the region. Hardy and robust, robins are incredibly adaptable and very adept at finding food. Second, there seems to be plenty of fruit and berries around which robins like to eat in the winter, from crabapples to American holly, and hawthorn to dogwood berries.
Third, most of the robins in Massachusetts right now are probably not New England robins. Petersen says most of our summer robins are probably already wintering in the southeastern United States and many of the ones we are seeing during the winter are likely from further north. They are eating the last remaining winter fruit and once it’s gone, they’ll in all probability move south too – but probably not as far south as our breeding robins.
“We often get calls at Mass Audubon in February that robins are back, when in fact the birds have probably been around most of the winter’’ said Petersen. He said the same phenomenon of variable numbers from one winter to another also applies to other partially migratory species such as blue jays and chickadees.
“It’s all about food. It’s the thing that ultimately determines their winter distribution and abundance.”
Now, quite likely you may not have noticed these large numbers of robins. That’s because the birds tend to disperse widely during the day over enormous areas and only return at dusk to these gigantic roosts in dense vegetation. They aren’t particularly noisy so unless you are very close to a roost, you may not even be aware that there are thousands of birds spending the night in your neighborhood.
So say hello to the robin. But not to spring.