Monday, March 19, 2012

The Month of Hope Denied impersonates April

My instinctive reaction to 70 degree days in early spring is to run, run to a migration hotspot and start tracking down Northern Parulas. However it's still mid March and there's barely a Parula north of Florida. So here we are in March, with a largely typical array of March migrants (Pine Warbler, Tree Swallow, Eastern Phoebe) in weather that we normally associate with the ramp-up of migration in mid-late April. I've been colder than this in May.

Since warblers in central America don't surf Accuweather for the boreal forest weather forecast, it seems likely that spring will be only a little early in terms of warbler migration - they still have to fly trans-Gulf and up the Atlantic coast before making it to NYC and it's not an overnight job. Warmer weather might accelerate that by a few days or a week. The birds that might turn up early would be things like Eastern Phoebe and Louisiana Waterthrush (and even N. Parula) that have significant continental wintering populations - things that you can see in FL in February. But migration is probably triggered by day length, so it's not like the rest of the genus formerly known as Dendroica (now Setophaga) is going to turn up four weeks early. Even Fox Sparrow migration doesn't seem to be at full bore right now (although they may simply have overwintered further north this year) - on time migration should be the next three weeks.

So in the interim I've been waiting out the good weather and going to see the flock of Rusty Blackbirds in Bristol PA or watching the gull flock dwindle in Levittown PA.

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