When, where, and how far will birds migrate? Our migration forecasts will answer these questions for the first time.
Generally unfavorable migration conditions prevail in the West this week, with those pulses of movements that occur featuring Green Heron, Least Sandpiper, Short-billed Dowitcher, Pacific-slope Flycatcher, Common Yellowthroat, and Clay-colored Sparrow, while the East sees a return to more summer like conditions until more favorable conditions and associated moderate flights of Common Nighthawk, Ruby-throated Hummingbird, Red-eyed Vireo, Blue-winged Warbler, Blackburnian Warbler, and Chipping Sparrow come after the middle of the week.
Moderate and some locally heavy migration was heavily featured across the continent during the past week, with the West seeing pulses of Northern Shoveler, Northern Pintail, Green-winged Teal, Solitary Sandpiper, Pectoral Sandpiper, and Orange-crowned Warbler among other migrants and the East seeing movements including Piping Plover, Solitary Sandpiper, Caspian Tern, Chestnut-sided Warbler, Magnolia Warbler, and Baltimore Oriole.
Favorable conditions early in the period will bring moderate movements featuring Northern Pintail, Warbling Vireo, Swainson's Thrush, Wilson's Warbler, and Western Tanager in parts of the West, particularly the Pacific Northwest, while a passing cold front early in the week will bring moderate to locally heavy movements of Warbling Vireo, Red-eyed Vireo, Veery, Blue-gray Gnatcatcher, Ovenbird, Northern Waterthrush, Blackburnian Warbler, Chestnut-sided Warbler, and Rose-breasted Grosbeak in its wake before southerly flow slows down the system in the East.
Scattered light to moderate movements featuring American Wigeon, Sanderling, Yellow Warbler, Wilson's Warbler, and Yellow-headed Blackbird highlighted the week in the West, while Black-bellied Plover, Wilson's Phalarope, Common Nighthawk, Least Flycatcher, Chestnut-sided Warbler, Yellow Warbler, and Wilson's Warbler composed generally light early period and increasing moderate and even isolated heavy later period movements in the East.
A brief pulse of light to moderate flights that will include American Avocet, Marbled Godwit, Western Sandpiper, Western Kingbird, Barn Swallow, Black-headed Grosbeak, and Bullock's Oriole on either end of the forecast period highlight otherwise unfavorable conditions across the West, while a relatively weak front drifts east mid week bringing light to moderate flights of Osprey, Greater Yellowlegs, Semipalmated Sandpiper, Ruby-throated Hummingbird, Purple Martin, and Tree Swallow first to the northern Plains, then the Great Lakes, and finally the Appalachians and portions of the eastern seaboard.
All but the latest of migrants already passed, this week saw in the primarily scattered light and highly localized moderate movements across the West, with late migrants featuring Olive-sided Flycatcher, Willow Flycatcher, Cedar Waxwing, and Townsend's Warbler, while the East saw its light to moderate flights concentrated in the center of the country and featuring primarily departures of Least Sandpiper, White-rumped Sandpiper, Short-billed Dowitcher, Cedar Waxwing, Swainson's Thrush, Tennessee Warbler, Blackpoll Warbler.