BirdCast: real-time migration information

By Team eBird 2 Apr 2018

The Cornell Lab’s BirdCast project has two incredible new features: a 3-day migration forecast for the entire continental US and a live migration map for the same region. Check out how these new features allow you to discover migration like never before!

  • The migration forecasts give you a quick glance at what to expect for the next three days, with predictions based on weather forecasts combined with radar data from 23 years of spring migration. These forecasts are updated daily. Check in regularly to plan when you’ll hit migration traps looking for new arrivals, and when you might go to check in on migrants that might be deciding not to migrate. This is the culmination of many years of research and data science.
  • The live migration maps take data from weather radars, which can detect migrating birds, and package them up into quantified maps: one for each night of migration. Each animation packs a wealth of information, with shading showing migration traffic rates: the estimated number of birds migrating per hour across any given kilometer in the continental US. The little moving arrows can be mesmerizing, revealing not only the areas with significant migration but also the general direction of birds’ movements. Running from just before sunset to about noon of the following day, each night can be played as an animation: watch how the bird migration ramps up 30-45 minutes after sunset each night! This live map is updated every 10 minutes, every night, all season long. You may want to start checking its up-to-the-minute info each morning before you head out to go birding, or peruse past nights to see how well they predicted what you found the following morning.

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Migration on the night of 29 March 2018 was moderate to heavy across the Southeast US, with some light migration on the Great Plains and in California. Most other areas did not see much nocturnal migration. As expected in spring, most birds are moving in a northerly direction, although the exact direction varies by geography and local weather.

Note: The lower 48 United States is the only broad world region that provides a freely accessible archive of radar data to the public in a standardized format. Unfortunately, this restricts the current BirdCast approach to the continental United States. We look forward to the possibility of expanding to other regions in the future.