Coots and Night Migration

You may have noticed that the coots are congregating on certain lakes and marshes in our region. As with some other birds, they congregate in large flocks before heading south for the winter. I have been watching the coots congregate on Lake Metigoshe, and they are actually quite fun to watch as they swim around, dive, and in other ways live up to their reputation. We see the coots staging on the lake now, but one of these mornings we will look out on the lake and there they will be: all gone!

With the exception of owls and perhaps nighthawks, we think of birds as being active during the day and sleeping at night. When it comes to migrations, however, it can be quite different. Coots and many other birds migrate at night.

We’ve all heard geese flying overhead at night during the spring and fall migrations. You may not be aware that many if not most birds migrate at night. Like the geese, many birds call during their migration, so scientists are using recording devices and software to track these night migrations. Even astronomers with their telescopes focused on full moons during spring and fall migrations have recorded upwards of 9,000 birds an hour passing through their field of view.

Why do these birds migrate at night? It might be to avoid predators such as hawks that would be encountered during daylight hours. It may also be that during the daytime they need to feed and rest a bit before the next leg of their journey. Maybe it’s a little of both. Basically migrating birds either have to feed regularly during their migration or have stored up enough fat to get them to their destination. Coots are known to be weak fliers, so I’m guessing they must stop and feed regularly. At any rate, they’ll spend their winter along the Atlantic coast or perhaps Mexico or Latin America.

You’ve probably heard the persistent rumor that coots actually don’t fly south for the winter. They simply could not be smart enough to find their way. These people have speculated that the coots are actually whisked away in the dead of night by a fleet of busses. So keep a look out for a fleet of unmarked buses in your area this fall. If we are all vigilant, perhaps the great coot migration mystery can be solved right here in North Dakota.

Chuck Lura

Natural North Dakota is supported by NDSU Central Grasslands Research Extension Center and Minot State University-Bottineau, and by the members of Prairie Public. Thanks to Sunny 101.9 in Bottineau for their recording services.