robins in the snow

A post on the new blog Home Bird Notes regarding the author's surprise at seeing American Robins (Turdus migratorius) in winter on the Jersey shore struck a familiar note with me.  The robin's reputation as a harbinger of spring is probably only legit somewhere north of, say, the Mackinaw Bridge.   

Plenty of data show the northerly distribution of wintering robins.  The first map was produced from 30 years of Christmas Bird Counts, which take place the last few weeks of the year.  It shows at least some robins well into Canada.  Although robins are not really birds that show up at feeders (they'll eat raisins, dried apples, and chopped fruit in a pinch, though), many Canadians have reported them to Project FeederWatch as, the graph shows. The last map is from the 2005 Great Backyard Bird Count, which is held over a weekend in late February.  Even that late in the season, there are few areas in the Northeast or upper Midwest that didn't record robins.

That there are so many robins in the northern U.S. in the winter comes as a surprise to many people, although it's hard for me to fathom how scores of my campus coworkers somehow miss the December flocks of robins stripping the crab apples right across from the parking structure.  These folks probably just don't realize that the limiting factor over where robins spend the winter is primarily food.

Robins, like other members of the thrush family, rely heavily on fruit in the non-breeding season.  Mountain ash, grapes, Virginia creeper, poison ivy, crab apples, hawthornes, pyracantha, cedar, and holly are just some of the species eaten by robins in the winter.  Some get left until late in the season; around here viburnums and buckthorn are the last to go. The proliferation of fruiting ornamental shrubs in developed areas may be contributing to what appear to be increased numbers of robins spending at least part of the winter in northern areas.

Temperature plays a more minor role in whether or not robins stick around.  Prolonged cold requires more energy for the birds to stay warm.  This could result in food crops being used up faster, in which case the robins might move on.  Unfrozen water is probably attractive to them, even though birds will eat snow as a water source.  If the ground is bare and temperatures are fairly warm, robins will forage for invertebrates much as they do in the summer, so they tend to move out of areas where there is a lot of snow cover. If warmer winters are a result of global climate change, we could expect even more robins to find favorable winter conditions at increasingly higher latitudes.

If you are looking for a better signal that spring has arrived (at least if you are around 42 degrees north latitude in the Midwestern U.S.!) it might be Common Grackles, which winter very sparingly here.  I can expect to see substantial flocks in early February.  But is that really spring?  There are many cruel cold and snowy days well after that time.  Personally, I await the first insect-eating migrants before I declare spring has sprung.  Birds like the Eastern Phoebe, or one of my favorite species, the Black-and-white Warbler.

On the other hand, maybe the remedy for the winter blues is to "think spring" each time you see a robin eating frosty berries in the snow.

Robin photo by Cindy Mead at Woodsong Nature Photography.  Fox grape photo by Mark O'Brien of Random Photo Blog.

Comments

[John]

Grackles, phoebes, and catbirds aren't good harbingers of spring for me since I have seen all of these in the first week of the year. Usually the arrival of tree swallows is a better sign, since these come in large numbers around the end of March.

[P.M.Bryant]

Here in south Texas, it ain't spring until the robins disappear.

The scissor-tailed flycatchers are our harbingers (well, mine, at least).

[Pamela]

For me it's the red-winged blackbird that signals spring, even though there are apparently some wintering not far from me (I hear reports--I haven't seen them). Spring is when the flocks arrive and I hear the first one sing.

[Home Bird]

Hi Nuthatch: Nice to see you pick up this thread, provide more info, and post some excellent maps. I started paying attention to birds as a child in the Berkshires in Western Massachusetts, where winters were colder and longer than here or in central Michigan where I was born (and where you are, I think). I don't remember robins in Western Mass in winter. Further south I have certainly seen them occasionally all year. But this year there seem to have been many more than usual (from what I gather from people who have been here longer than me). After my first post about them I later saw a flock of 40 or so flying overhead.

The temps here have been way above normal--several spells near 70 for days in a row in January. I'm not counting on it lasting (and don't particularly want it to--although the occasional nice day is a gift, too many seem odd and unnatural to me). I haven't been here long enough to know what the real harbingers of spring should be, but I will be looking for the osprey which were overhead every day last summer.

[Rurality]

Even in Alabama people will still tell you that Robins "return in the spring"! I think people just start feeling spring-ish, look out their windows, and say, "Hey, Robins! It must be spring..." Most people who don't look for birds don't really see birds.

For me, "spring is here" when I hear a waterthrush.

[Clare]

About 6 or 7 years ago a Robin was found in Iqaluit, and it probably fared better than the barn swallow I saw here in Arctic Bay in early June my first year here. There wasn't much in the way of flying insects for him at that time of the year.

When I was in Ft Providence, one of the best harbingers of spring were the Mountain Bluebirds. Suddenly there was a profusuion of blue against the remaining snow banks. Of course eagles made back well before them.

Up here, I guess it would be the Snow Buntings that announce our spring.

[TroutGrrrl]

Like Pamela, I also feel more 'springy' when I begin hearing red-winged blackbirds. And tree swallows. We have robins almost year-round on campus - they hang around the greenhouses where the exhaust fans keep the ground warmer, and presumably, buggier.

Hey, swanky new address Nutty!

[Dave]

The robin also visits here. Unfortunatly spring is a little ways off yet. Our temps have been above freezing during the day though.