Wednesday, April 11, 2012

Big Weekend Coming April 14-15

Leading the warbler parade: This weekend, large numbers of Yellow-rumped Warblers should arrive in the migrant traps of northwestern Ohio, with the adult males stunning in breeding plumage. Photo by Kenn Kaufman.

April 11, 2012: For the last several days, with only a brief break on Saturday night, conditions in northwest Ohio have not been favorable for migration. Winds have been mostly from the west-northwest, and temperatures have been a little below average for the dates (a major change from the above-average temperatures that dominated in March).  So for the last few days, the arrival of new migrants has been reduced to a trickle.

Conditions are setting up for that to change in a major way this weekend.  The exact timing of these weather events is still uncertain, but forecasts agree that an approaching high-pressure area will pass over and move to our east sometime on Friday.  By Friday night, with a high-pressure area to our east and a line of low-pressure centers to our west, there should be a strong southerly flow of air coming up to Ohio all the way from the Gulf Coast.  This flow should become even more pronounced through Saturday and then Saturday night.  We’re likely to get some showers as well, and if there are major rains to the south of us overnight they could put a damper on the migration.  But all indications are that we’ll have a very big arrival of migrant birds this Saturday and Sunday, April 14 and 15, when the current weather dam breaks and the birds can flow north. 

This early in the season, of course, we won’t see as much variety as we would in May.  There should be large numbers of kinglets (both species), the first big push of Yellow-rumped Warblers along with some Palm Warblers, probably more Hermit Thrushes and Brown Creepers, the first major pulse of White-throated Sparrows, and other typical April birds.  This flight should also produce a scattering of other warblers that are usually among the vanguard, such as Black-throated Green, Black-and-white, Nashville, and Northern Parula.  Orange-crowned Warbler, always scarce, often shows up with this early push.  This is also a good time to look for southern species overshooting their breeding ranges, such as Louisiana Waterthrush and Yellow-throated Warbler.

If the winds are southwesterly during the day on Saturday or Sunday, not just southerly or southeasterly, we might get another significant hawk flight, including the first big push of Broad-winged Hawks for the year. 

At any rate, all of the current weather forecasts now suggest that this will be an excellent weekend for migration in northwestern Ohio.  If you can arrange your schedule so that you can get out, it could be a lot of fun out there!

Many thanks to Mark Shieldcastle for sharing his expertise on the timing of expected bird species and on the effects of weather patterns on migration.  But if these predictions for the migration don’t bear out, I take full responsibility!

1 comment:

Drew Weber said...

Really looking forward to some south winds! After that long early push of south winds, things have been pretty slow. Leading a field trip for the Penn State Ornithology class in central Pennsylvania on Saturday so I am really hoping to get a good push and maybe find gnatcatcher and Palm Warbler.

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