Tuesday, May 15, 2007

Magee area migration 5/15

As predicted, there were strong winds from the southwest last night and this morning, and many new migrants were evident this morning (Tuesday May 15) in the vicinity of the boardwalk at Magee Marsh, n.w. Ohio. The influx was most obvious to those of us who started off the morning along the north edge of the woods, on the edge of the parking lot and access road, where the first sunlight was hitting the trees and where there was more shelter from the wind. Birders who arrived and immediately took the boardwalk straight into the woods were generally less impressed with today's numbers. But it seemed clear to me that at least some species were more abundant than yesterday.

Conspicuous among the birds moving on the outer edge in the morning were Blue Jays (50-plus, in flocks moving over), Cedar Waxwing (about 50), and Indigo Bunting (15). About the same warbler species were present today as yesterday, but there were distinct changes in relative abundance, with a lot more Blackpoll Warblers (I saw/heard 10 today, 1 yesterday), Tennessees (8 today, 1 yesterday), Black-throated Blues (18 today, 8 yesterday), and American Redstarts (40 today, 20 yesterday). Chestnut-sided (15), Magnolia (20), and Bay-breasted (12) were still common, but less so than they had been. I had at least 20 Red-eyed Vireos and 3 Philadelphia Vireos, but not a single Ruby-crowned Kinglet today. Those are just my personal numbers from four hours on the boardwalk and vicinity, to give a sense of relative abundance, not any attempt for a complete number. The strong wind made it hard to detect birds by sight or sound and I probably found fewer than I would have under calm conditions.

An interesting note on the differences between perceived and actual bird numbers. Kim was at the main banding site for the Black Swamp Bird Observatory early in the morning before coming to join me on the boardwalk in late morning, and she pointed out that on very windy days, the total catch at the banding station seems to be reduced. Evidently the wind makes it easier for birds to see and avoid the mist nets. Also, some of the birds that were evident at the boardwalk today, such as Blue Jays and Cedar Waxwings, are high fliers that don't wind up in the banders' nets very often. So, while the banding station totals are more standardized than counts taken from field observation, they're not immune to being skewed by outside forces. All the more evidence of the fact that it takes serious attention and thought to really detect what's going on with bird numbers.

This evening there were strong storms that came through the area after 7 p.m., with near-tornadic conditions in our little burg of Rocky Ridge, and the wind shifted abruptly to the northwest. It has since shifted back to the WSW, but I expect consistent northwest winds by morning, with cooler temperatures. I doubt that many birds left tonight, aside from those that were blown right off their perches and into the lake! Numbers should still be decent tomorrow but I plan to go look at water areas to see if any odd migrant waterbirds might have been put down by the storms.

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