Friday, April 20, 2012

Migration outlook April 21-24

Black-throated Green Warbler: Typically among the early arrivals. At least a few have come in to the migrant traps in northwestern Ohio as of April 20. Photo by Kenn Kaufman.
April 20, 2012, evening:  As I write this, the wind is shifting from southwest to northwest.  Winds are predicted to stay northerly for at least the next three days and nights, which would mostly shut down the migration for a while.  Fortunately for birders here, a good diversity of new arrivals came in during the last couple of days, so we'll have some variety to keep us going while we wait for the next big influx.

As predicted earlier, winds were out of the south from Wednesday morning through Friday afternoon, with a stronger flow developing by Thursday night, and these conditions brought in many migrants, especially on Thursday and Friday.  The most conspicuous arrivals were Yellow-rumped Warblers, now present by the dozens in every woodlot close to Lake Erie, but many White-throated Sparrows came in also, and lesser numbers of Ruby-crowned Kinglets, Palm Warblers, Blue-gray Gnatcatchers, House Wrens, and others. 

However, perhaps the most notable phenomenon was the wide variety of other migrants that showed up in small numbers. Between the Magee Marsh boardwalk and the BSBO main research site (Navarre unit of Ottawa NWR, a few miles east of Magee), I heard reports of at least 18 warbler species in the last two days. Most of these were present only in very small numbers, but they included such choice species as Cerulean, Orange-crowned, Prairie, Prothonotary, and Hooded warblers.  Other species arriving in small numbers included White-eyed Vireo, Wood Thrush, Baltimore Oriole, and Gray Catbird. 

All of the preceding are nocturnal migrants that would have come in overnight, but there was some daytime migration happening recently as well. Flocks of Blue Jays have been moving along the Lake Erie shoreline, Chimney Swifts showed up in numbers on Friday, and Friday also saw a movement of flocks of American Goldfinches and some birds of prey.

Looking ahead:  Based on current weather forecasts, I don't expect any big arrivals of birds from now through Tuesday, April 24, at least.  There might be an influx on Wednesday, or it might not happen until next weekend.  But in the meantime, a wide variety of birds have moved into the area, and most of them should stick around.  If you have a chance to get out more than once, try checking multiple spots.  If the northerly winds are strong, some of the migrants might relocate to larger woodlots (such as some of those in East Harbor State Park) or those that are back a mile or two away from Lake Erie (such as the woods at Ottawa National Wildlife Refuge). 

The auto tour at Ottawa NWR is open both days this weekend, April 21 and 22, from 8 to 4.  Refuge manager Jason Lewis told us that the entry point for the auto tour route is shifting from the old east parking lot to the visitors' center parking lot.  There should be good numbers of Dunlins, yellowlegs, and other shorebirds at a couple of points along the route, especially the impoundments MS 7 and MS 4.  A map of the auto tour route is here.

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