4.11.14

Georgia in Fall

I was down in Atlanta the last few days for work. The migrants I'd seen passing through New York a few weeks are go are still moving through the north Georgia mountains. I headed out early along the Chattahoochee, one of my favorite rivers.

The riparian forest in these bottomlands is, in places, genuine old growth, and today it was alive with woodpeckers - that most sedentary of families - as well as migrants.

In fact, I had a six woodpecker morning, with what looked like a mated pair of pileated, a lone red-headed, and countless downies, sapsuckers, red-bellieds and flickers.

One big oak showed how foraging strategies differ to avoid niche competition, with the downies all at the outer reaches of the tree, the sapsuckers focussing slowly and methodically on the forks of the main trunks, and the red-bellieds more flighty and opportunistic. 


                                       


This got me wondering why there is high woodpecker diversity here. And about radiation within the woodpeckers generally. 

If woodpeckers are sedentary, and don't show much behavioral plasticity, why are they so successful in these kinds of forest? How can they sustain such diversity? Is woodpecking a really great niche? 

Maybe. It's a niche that's also been exploited by other birds that lack competition from woodpeckers, especially on islands, which woodpeckers haven't been great at colonising; vangas in Madagascar, crows in New Caledonia. 

Or maybe woodpecking is really lots of niches? So the lack of plasticity in behavior is part of the reason they've been able to radiate into sets of close-living specialists. 

Whatever, they're one of my favorite families, so seeing a bunch every time I walk through these forests is always great. 

On the way home, browsing amazon for woodpecker books, I saw the snow had already hit the ridges of the southern reaches of the Appalachians a few hundred miles north over the Tennessee border.

                                   

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About Me

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NYC, Buxton, Buenos Aires
I work in NYC and own a wildlife and wilderness agency specializing in the southern cone of South America. I still do some guiding down there, especially looking for Fuegian and Patagonian avifauna. I'm particularly interested in the wintering ecology of neotropical migrants, and in avian biogeography in general. You can follow me at - @domhall And find me at - AventuraArgentina.com