ANN ARBOR, Mich. – Around 10 p.m. on Thursday night, 10,800 birds were flying over Washtenaw County, and 4,500 had completely crossed over the county.
From mid-April to mid-May migrating birds fly across the United States to return to their homes after migrating south for the winter. BirdCast, a data-driven forecast and bird migration website, predicts how many birds, and which kinds of migrating birds, are passing through different parts of the United States.
Its live feed of migration activity can be narrowed down to individual counties across the country.
The website not only gives lives numbers of birds flying over an area, it also shows historic numbers, the altitude of nocturnally migrating birds, the number of how many have crossed the county for the season and which species are likely to have passed by.
In Washtenaw County, these species include the blue-gray Gnatcatcher, the ruby-crowned Kinglet and the Pine Warbler.
Earlier in April, an estimated 46,000 birds flew over the county in a single night. In March, only around 18,400 made it across.
According to BirdCast, “Birds usually begin to migrate 30 to 45 minutes after sunset, with the greatest number in flight two to three hours later.” This means that Washtenaw County residents can anticipate the most activity from nocturnally migrating birds to be between 10:30-11:30 p.m. if sunset is around 8:30 p.m.
BirdCast was created in 1999 by the Environmental Protection Agency, the National Audubon Society, Cornell Lab of Ornithology, Clemson University Radar Ornithology Laboratory, the Academy of Natural Sciences in Philadelphia and GeoMarine, Inc.
Now, the project has several more partners, such as NASA, Microsoft and Amazon Web Services to use research analysis and machine learning to develop updated visualizations for BirdCast users.