Robins That Don't Fly South

[hotcoldhot]

I live in Illinois and I noticed during the winter as soon as the weather gets above 32ºF I see two robins. Today it was very warm and I saw four of them.

We have a lot of robins where I live and by late September / early October they are almost all gone.

But for the past years I always noticed a couple of them don’t leave. I am assuming they don’t migrate because somehow they are getting food.

My question is why don’t they fly south? Is the food alone enough to stop them. And if so why don’t more robins stay up north. The robins I see must hide when it gets really cold but when it warms above freezing I always see this pair (I don’t know where these other two came from today). They don’t look thin or sick so they are getting food and appear totally normal

[Fetchund]

Robins will often stay north if the food supply is adequate. They subsist primarily on berries that stay on trees and bushes, so you mainly see robins in areas that have a lot of landscaping. They really like crabapples and mountain ash in winter. There may also be a few people around you stocking feeders with berries and/or mealworms.

Some years you will see more than others, but it is getting increasingly common further north to see a few. When I lived in mid-Michigan we always had a few. Heck, this winter some folks have been seeing bluebirds in Minneaota!

If more robins stayed north, there wouldn’t BE enough food to sustain them.

[Sal_Ammoniac]

I do think the migration patterns of robins, along with a lot of other birds, have changed significantly in recent years. Here in Boston, I saw a whole tree full of robins the other day. There must have been a dozen of them. So where’s my spring, I ask?

[DSYoungEsq]

Everything you want to know about Robins at Wikipedia.

[Squink]

Global warming: Are migration patterns a-changin’?

“There is a pretty clear-cut pattern,” says University of Wisconsin-Madison wildlife ecologist Stanley Temple, who has worked with Leopold’s data. “Some birds are shifting the timing of their migration in response to climate change, but others clearly are not.”

Temple points to two closely related species, the robin, a short-distance migrant, and the wood thrush, which migrates to Central and South America. The wood thrush arrives on May 6, just one day earlier than in Leopold’s time, but robin arrivals have moved up from March 26 to March 5 – 21 days in just 60 years. Plenty of robins now even spend the winter in Wisconsin.

Why the difference? “They are using different cues to time their migrations,” Temple explains. “Short-distance migrants are much more influenced by the temperature regimes in North America, while the timing of migration for long-distance migrants is almost all due to the photoperiod [day length].”

There are non global warming dependent possibilities too:
The Winter Banquet

A few decades ago, most of the birds that fed in North America’s backyards ate weed seeds and insects gleaned from crevices in tree bark. Now they’re presented with other feeding options. Nearly one-third of the adult population of North America dispenses about a billion pounds of birdseed each year as well as tons of suet and gourmet “seed cakes.” What changes does this largesse impose on our native birds?