Wednesday, November 12, 2014

Where are the Robins?

Ed Gaillard: birds &emdash; American Robin singing, Central Park
Have you seen me?

I haven't been seeing many Robins or Cardinals lately. Usually at this time of year, there are Robins by the dozen in the Ramble and on Cedar Hill and, oh, pretty much everywhere. Not this year; I've gone days without seeing any, and when I see them, there's only a handful. Cardinals are normally quite plentiful as well. Not this Fall.

American Robins are normally migratory--it's right in their name, Turdus migratorius--but over the last few decades, more and more of them have wintered in the New York area. These are probably short-haul migrants (birds from upstate or New England moving here for the winter, while birds that summered here go down to Maryland or so, and birds from there move farther south). This year, they seem to have skipped the City and gone on south.

Northern Cardinals are sedentary--they don't migrate, they stay in their nesting areas year-round. But there were a plenty of them this summer, and very few now.

On the NY state Birds mailing list today, Shai Mitra has noticed something odd going on as well:
Back around the end of September there was a thread on this list regarding recent incursions into NYS, not only of classic irruptives such as Pine Siskins and Red-breasted Nuthatches, but also of more cryptic migrants, such as Downy Woodpeckers. [...] Since that time, the data have strongly confirmed that not only Downy Woodpeckers, but also Hairy and Red-bellied Woodpeckers and White-breasted Nuthatches (and even Northern Cardinals!), are all staging major irruptions this year.
I was part of a group that conducted a stationary morning flight count [at Robert Moses SP, Suffolk County], and my companions will attest that our total of 5 Hairy Woodpeckers had me freaking out a little bit.... Among other relatively (or allegedly) sedentary species moving this morning were 12 Downies, 20 Red-bellies (possibly a local daily max), and a White-breasted Nut, and our total of 28 Northern Cardinals in obvious morning flight was a true spectacle of nature!

Ed Gaillard: birds &emdash; Cardinal, Central Park
not a classic irruptive

So what's going on? why are these birds on the move?

Sometimes people try to forecast the winter by the birds. "Oh, they're staying north this Fall, must be a mild winter coming", or "Everything went through early, hard winter ahead". I'm not sure that makes a lot of sense. How would birds know what was coming? Weather forecasting is hard.

You can see how it would be a big evolutionary advantage, though, especially for sedentary and short migrants. If you're a bird that normally stays on its nesting territory, and you knew that the winter was going to be harsh, you'd move. But, Central Park lost most of its Carolina Wrens in last winter--surely they'd have moved out if they'd known how harsh it was going to be.

I don't know. Last winter's harshness was very unexpected. The Fall was so mild, do you remember? Maybe the birds got caught by surprise. Maybe this year, they know what's coming.

What are you seeing where you are? What are the Robins, Cardinals, and woodpeckers doing?

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