When will bird migration peak in your area? (American Bittern photograph by Paul Konrad.)

If you are wondering when bird migration will peak in your area, a list of the peak migration period for birds in the 1,000 largest cities in the Lower 48 States is available now courtesy of BirdCast. The “peak periods” are the date ranges when 50 percent of all nocturnal bird migration takes place over each city. This peak period was determined by examining radar information of bird migration collected during the past 25 years. Knowing when the peak period of migration takes place in an area can help inform people who plan birding activities, engage public interest, and inform conservation action.

An important example is how the period of peak nocturnal migration can inform people, businesses, and city leaders that it is important to participate in turning lights off to reduce bird-building collision risks and other hazards created by light pollution for migrating birds (birds can become disoriented by lights in buildings, which creates building collision problems). One other thing to keep in mind is that the peak migration period in your area probably happens before you might expect, so take a look – some peak periods begin in August, other in September. If you don’t find your city on the list, check on a nearby city in your state, and that should be applicable.

To check on peak migration timing in your city or a city near you, refer to Peak Fall Migration Windows for 1000 U.S. Cities - BirdCast and click on the bold sentence at the end of the short article that reads: Peak Fall Bird Migration Periods for US cities.