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

Showcasing the spectacle of bird migration

When, where, and how far will birds migrate? How many birds passed last night? Our tools help you explore the answers to these and many other questions about bird migration.

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Migration tools


Explore nightly migration data in your region.  Learn more

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 Diya Balagopal The Cornell Lab Oct 16, 2023

The past week saw another movement above the half a billion mark, with continued high intensity flights predicted for 16-17 October. Let's get those lights out, especially in the areas with red alerts.  Read more

Forecast and Analysis
By Diya Balagopal Guest Authors Oct 09, 2023

In recent days we've hit the highest highs and lowest lows of this migration season. Here, we speak briefly about the last week's events and highlight the upcoming movements and action alerts for the next three days.  Read more

By Andrew Farnsworth The Cornell Lab Oct 07, 2023

Migration intensity goes off the charts - the BILLION bird barrier is shattered!  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