MYSTERY OF THE MISSING MIGRANTS | © Charley Harper Art Studio | Used with Permission

Bird migration forecasts in real-time

When, where, and how far will birds migrate? Our migration forecasts will answer these questions for the first time.

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Migration tools


Bird migration forecast maps show predicted nocturnal migration 3 hours after local sunset and are updated every 6 hours. Colorado State University and the Cornell Lab of Ornithology currently produce these forecasts.
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Search with our local migration alert tool to determine whether birds are passing overhead near your city tonight!
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See real-time analysis maps of intensities of actual nocturnal bird migration, as detected by the US weather surveillance radar network between local sunset to sunrise. Cornell Lab of Ornithology currently produces these maps.
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Recent news

By Benjamin Van Doren The Cornell Lab Jun 07, 2021

The BirdCast team led a study published today that uses two decades of data to show that migration magnitude, light output, and wind conditions are important predictors of collisions at a high-profile building in Chicago. This research has global implications for conservation action campaigns aimed at eliminating an important cause of bird mortality: light pollution and resulting collisions with structures.  Read more

By Andrew Farnsworth and Adriaan Dokter The Cornell Lab Jun 01, 2021

The spring of 2021 offered many migration highlights, and here we showcase the top 5 mega-flights of this soon-to-be-in-the-books season.  Read more

By Adriaan Dokter The Cornell Lab May 22, 2021

During the past week, enormous numbers of birds have been migrating through the US. But birders seeking massive concentrations of birds in their favorite habitats may not have experienced the fallouts of their dreams. A new visualization depicting the altitude of migration, when viewed in conjunction with the distribution of migration traffic, highlights an explanation.  Read more

All news

NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA's Goddard Space Flight Center

Lights Out

Every spring and fall, billions of birds migrate through the US, mostly under the cover of darkness. This mass movement of birds must contend with a dramatically increasing but still largely unrecognized threat: light pollution.

BirdCast Partners and Support

BirdCast is a consortium of interdisciplinary researchers, primarily from three organizations at present, with a growing list of collaborators, supporters, and partners.  Learn more

Core partners

Core funders

Other support

Lights Out partners