NEWBURYPORT — Usually by this time of year, sightings of bald eagles over the Merrimack River are an everyday occurrence.
But this year, the graceful birds have been barely visible. As happened last year, you can blame the unusually warm weather.
Bill Gette, director of Massachusetts Audubon Society’s Joppa Flats Education Center in Newburyport, said the warm weather both here and in the bald eagle’s northern habitat has prevented rivers from freezing. Fish are a major part of the eagles’ diet, and so there’s been no need for the birds to head south to find open, fishable water.
“Why leave if there’s plenty of fish?” Gette said.
Even so, there are a handful of eagles in the area. They are considered to be the “resident population” because they have nested in this area in the recent past. The most recent nest report came from Amesbury, where a nest was made near the confluence of the Merrimack and Powow rivers.
Steve Grinley, owner of Birdwatcher’s Supply & Gift in Newburyport, said perhaps 10 to 12 eagles are in the region.
Both Grinley and Gette said that locals can expect the usual influx of eagles later this winter, when rivers finally freeze and the majestic birds make their annual migration. When that migration occurs, bald eagles can frequently be seen around Deer Island in Amesbury and around Cashman Park in Newburyport. The eagles seek open water in which to hunt for fish, and they also prefer to find tall trees along the riverbank that have open branches for perching.
Another notable bird that made quite a splash in the local area last year has returned, though not in the record-setting numbers that marked last year’s appearance.
Snowy owls have been sporadically seen at Salisbury Beach State Reservation and on Parker River Wildlife Refuge, Gette said. They have also been seen at Logan International Airport in Boston. The large birds come down from their arctic habitat to hunt for small game, such as mice.
Last year’s mass migration was caused by a steep decline in the lemming population. Lemmings are small arctic mammals, about twice the size of a mouse, that make up the staple of the owls’ diet. The lemming population dive was seen as a cyclical event, and it’s unclear thus far whether another mass migration of snowy owls will occur.