Big arrival of migrants 5/14

From Tuesday May 13 to today, Wednesday May 14, there was a huge amount of turnover in the bird population at the Magee Marsh boardwalk and other migrant traps on the lakeshore. It was a striking demonstration of how migratory waves can transform this area literally overnight.

Late Tuesday night, on a tip from Ethan Kistler, I looked at the radar pictures for the area and could see that a lot of birds had taken off just after dark to go directly north across the lake, while others were pouring in from the south. Today at the Magee boardwalk it was obvious that a lot of birds had departed overnight while a lot of different birds had arrived. This was clearly the point where the migration clicked over from the early wave to the main wave of arrivals. As recently as yesterday, Yellow-rumped Warbler (the early migrant) was the most numerous warbler in the area; today American Redstart and Magnolia Warbler were the two most numerous, with good numbers of several other species including Cape May, Black-throated Blue, Tennessee, Yellow, Blackpoll, and Black-and-white Warblers. Late-season migrants were well represented with Mourning, Canada, and a number of Wilson's Warblers. In about 4 hours on the boardwalk, despite a lot of rain, I saw 25 warbler species and heard reports of two others, and the total for just the boardwalk today may reach 30 species.

Other evidence of the main migration wave included a sudden increase in Red-eyed Vireos, numbers of flycatchers including Eastern Wood-Pewees and Great Crested Flycatchers, and great studies of Acadian and Least Flycatchers from the boardwalk. Yellow-billed and Black-billed Cuckoos, Orchard Oriole, and Philadelphia Vireo were among the other interesting migrants. Thrushes were in low numbers but included Swainson's, Gray-cheeked, Veery, and Wood. Rose-breasted Grosbeaks and Scarlet Tanagers were conspicuous again today.

At this point (3 p.m.) the rain has picked up again locally. I don't think that many of today's arrivals will leave tonight, so Thursday could also be quite good, but that assessment could change after I look at the latest weather forecast.