Magnolia Warbler © Ian Davies

Continental Summary

Several widespread pulses of moderate to heavy flights featuring White-rumped Sandpiper, Stilt Sandpiper, Ruddy Turnstone, Common Nighthawk, Eastern Wood-Pewee, Alder Flycatcher, Blackpoll Warbler, and Mourning Warbler punctuated the week across the East, while mid week moderate to locally heavy flights along the eastern Rockies were highlights of the period’s assemblage of Black Tern, Least Flycatcher, Dusky Flycatcher, Plumbeous Vireo, Swainson’s Thrush, MacGillivray’s Warbler, and Blue Grosbeak in the West.

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Upper Midwest and Northeast	Gulf Coast and Southeast
Great Plains	West

Upper Midwest and Northeast

Scattered light to moderate flights were the norm for the first half of the period, as more marginal conditions that included unfavorable winds, cooler temperatures and light precipitation moved into the region. By Tuesday and Wednesday many birds stayed on the ground, awaiting the arrival of more favorable conditions arriving from the West. Wednesday night saw these conditions reach the Mississippi, where moderate to heavy flights ensued. The end of the period saw these conditions spread to the Atlantic, with moderate to locally heavy flights from the central Mississippi River valley east through DelMarVa and the New York Metropolitan area.

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Alder Flycatcher © Ian Davies

Gulf Coast and Southeast

This week saw two primary dichotomies dividing the region, one geographic and one temporal. To the west of the Mississippi River, moderate to locally heavy flights were frequency during the period despite several large areas of passing, intense precipitation. To the east, heavier flights occurred, particularly after the passage of a very early tropical disturbance. In general these larger flights occurred earlier in the week, whereas primarily light to moderate flights prevailed later in the period (after the passage of a substantial cold air mass to the north and east).

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Wilson’s Warbler © Ian Davies

Great Plains

The weekend’s passing disturbance brought scattered moderate to heavy flights before its arrival and migration stoppage in its wake. A cool air mass with unfavorable winds kept birds on the ground for the days to follow, but a change came and quickly by Tuesday night. Warmer air and southerly winds ushered widespread moderate to heavy flights across the region, with some of these flights continuing on sequent nights; however, these subsequent flights did not have the extent nor the intensity of the mid week flight, as another disturbance dropping rain compartmentalized migration to the northern and then southern Plains states on Wednesday and Thursday nights, respectively.

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{ PHOTO }

West

A generally quiet weekend for the region, aside from the light to locally moderate flights in California and the Desert Southwest, became more lively during the beginning of the work week. Monday night saw more extensive light to moderate flights across the southern tier of the region, including moderate to locally heavy flights in and to the east of the central and southern Rockies. This area to the east of the Rockies continued to produce on Tuesday and Wednesday nights, although region wide movements were generally less intense through the remainder of the period. Note that eastern Montana ended the week with a moderate to heavy bang.

Swainson’s Thrush © Ryan Schain

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