Robins always have been a sign of spring, but that's changing, and only the robins know why.
Local bird experts only can theorize why a growing number of the birds are wintering in the Quad-Cities area rather than heading south.
Steve Hager, associate professor and co-chairman of the Augustana College biology department, said he has participated in the Audubon Society's Christmas Bird Count for 11 years, and "this is the first year I have seen literally hundreds of robins hanging out in scattered places throughout the Quad-Cities region."
He said he counted 300 robins on the Augie campus last Monday through Thursday, feeding on shrubs and ornamental trees such as crabapple and honeysuckle, which are the robin's main food source along with insects.
Available food likely is the reason they're staying, said Mark Graham, manager at Wild Birds Unlimited in Davenport. "They'd stay if there was a good food source."
Climate change also may be involved. Experts said robins are known as semi-hardies and can take the cold better than some birds but not as well as hardy birds such as blue jays and American crows.
Brian Blevins, owner of Pete Petersen's Wild Bird Shop in Davenport, said that, in general, semi-hardies "are not going as far south in the winter" and are "getting caught once big storms get in here," such as the only that slammed the area last week.
Mr. Hager said he has seen other semi-hardy birds, such as cedar wax wings, around the Augie campus this winter."Not as many as the robins, but still it's very unusual."
What is "south" also may be a matter of perspective, said Mary Lou Petersen, wife of the late Mr. Petersen and a member of the Quad City Audubon Society board. "Some (robins) are coming from Canada," and, for them, this is south, she said.
During migration, "we'll lose robins from here that stayed all summer," but those will be "replaced with ones that come from further north," Ms. Petersen said, adding that flying south is then "a matter of your perspective of how far north were you to start with."
Mr. Hager said, while some robins stuck around the area, "Ithink we can say with a fair amount of confidence that the robins that are here now probably came from the north" -- Wisconsin or Minnesota and the southern part of Canada.
Experts said bitter temperatures could be fatal to those wintering robins and other semi-hardy birds, and it's too late for them fly further south.
Mr. Hager said robins and other semi-hardies usually eat heavily throughout late summer and early fall to prepare for migration from late fall to early winter and a return to the area about mid-March.
In winter, there's barely enough food for them to eat to build the energy needed to regulate their body temperature, let alone to store enough fat to make it hundreds of miles.
Staying here is a risk for the birds, Mr Hager said. "It's like gambling. If you're wrong, this is the ultimate. You're dead."
He said no one can be entirely sure why semi-hardy birds are staying in the area.
"I don't understand what made the robins hang out," but "it's noteworthy. I'll tell you that."
Feed the robins!
Robins rarely eat at bird feeders. Area experts say if you want to feed robins, give them suet, raisins, or apples cut into pea-sized squares and placed on a plate out in the open. .