When, where, and how far will birds migrate? Our migration forecasts will answer these questions for the first time.
A period of generally favorable migration conditions featuring light to moderate flights of Common Nighthawk, Broad-tailed Hummingbird, Willow Flycatcher, Common Yellowthroat, Grasshopper Sparrow, and Western Tanager is in store for much of the West, particularly in the Rockies, while an unfavorable cool and wet start to the East gives way to later week moderate to heavy flights of White-rumped Sandpiper, Dunlin, Red-necked Phalarope, Black Tern, Black-billed Cuckoo, Red-eyed Vireo, Mourning Warbler, and Scarlet Tanager.
IMPORTANT NOTE: Team Birdcast is focusing on preparing for tomorrow’s Global Big Day, and as a result we haven’t been able to write a thorough forecast and analysis by our usual Friday deadline. Here is an abbreviated forecast, with weather maps and species lists; the analysis for the past week and potentially a supplemental forecast […]
Migration conditions will be generally more favorable across southern half of the West this week where moderate flights will feature Wilson's Phalarope, Red-necked Phalarope, Black Tern, Willow Flycatcher, Yellow Warbler, MacGillivray's Warbler, and Green-tailed Towhee, while midweek in the East will see the most extensive moderate to heavy flights of Black-crowned Night-Heron, Semipalmated Plover, Short-billed Dowitcher, Black Skimmer, Common Nighthawk, Black-billed Cuckoo, Acadian Flycatcher, Eastern Wood-Pewee, Canada Warbler, Blackpoll Warbler, and American Redstart in a pulse of significantly warmer air.
Moderate movements, particularly from California east through the central and southern Rockies, featured Black Tern, Cordilleran Flycatcher, Plumbeous Vireo, Swainson's Thrush, Black-headed Grosbeak, and Western Tanager and highlighted the period in the West, while moderate to heavy flights, particularly in the central and southern US, featured Common Nighthawk, Yellow-bellied Flycatcher, Least Flycatcher, Philadelphia Vireo, Veery, Magnolia Warbler, and American Redstart and highlighted the period in the East.
When birders in Cape May awoke on Monday morning, an interesting pattern was emerging (interesting is the norm in Cape May!). Numerous observers reported that numbers of migrants had arrived during and after the night and were still coming ashore from the Atlantic Ocean. The first real pulse of arrivals of this spring for a number of species had clearly occurred in Cape May. The combination of on the ground reports from eBird, nightly northeastern US radar data processing with BirdCast algorithms, and the excitement of spring arrivals inspired Team BirdCast to look a bit more closely at the events leading up to this movement.
Favorable migration conditions in the latter half of the period for the West will bring extensive light to moderate movements of Spotted Sandpiper, Olive-sided Flycatcher, Dusky Flycatcher, Warbling Vireo, MacGillivray' Warbler, Lark Bunting, Clay-colored Sparrow, and Chipping Sparrow, while a highly variable period for weather in the East will bring similarly variable and patchily distributed moderate to heavy movements featuring Least Sandpiper, Forster's Tern, Olive-sided Flycatcher, Least Flycatcher, Acadian Flycatcher, Wood Thrush, Swainson's Thrush, Golden-winged Warbler, Nashville Warbler, Cape May Warbler, Blackburnian Warbler, and Baltimore Oriole.