Robins, the theoretical harbingers of spring, have been in Boyertown all winter, including during the blizzard.
According to Jack Hubley, naturalist for WGAL-TV in Lancaster, robins stay through the winter. “They don’t need worms. When frost slams the door on invertebrates robins simply switch to a diet of fruits,” he says. There are many trees and shrubs that produce berry-size fruit that remains on the plant throughout the winter, providing easy pickings for robins, cedar waxwings, and many other fruit-eating birds, he adds.
While some robins do migrate, others stay in the area year-round. “Some robins might jump one, two or three states to the south, while others never leave,” Hubley says. He notes the robins in Boyertown could be from New York or Vermont or North Carolina. And likewise, robins from Pennsylvania can jump to other nearby states.
“Migration is anything but black and white; more like 50 shades of gray. Migration is tied to food availability, not temperature, and it’s triggered by hormonal changes tied to photoperiod. If migration were, in fact, dependent on temperature change, you’d certainly have a lot of confused critters out there,” Hubley says.
And, Hubley adds, don’t worry about the robins being comfortable in the cold. “Nature has equipped them with a down coat and a waterproof shell of feathers,” he says.
