5 surprising facts about bald eagles

December 14, 2015, 11:56 a.m.

1. These regal birds look magnificent but actually have a rather wimpy call. It's something that television and movie producers aren't terribly impressed with. So when you hear the cry of a bald eagle on television, what you're actually hearing is the call of the red-tailed hawk, which has a more fierce cry than its much larger cousin.

2. These huge birds are surprisingly social. They even have communal roosts, which are a very important part of their social lives. As the USFWS explains on a 2015 blog, "Communal roosts are usually in large living or dead trees that are relatively sheltered from wind and generally near sources of food. Many roost sites are used year after year and are thought to serve a social purpose for pair bonding and communication among eagles."

3. You may have thought the golden eagle is the largest eagle species, but actually the bald eagle is tied for size. With a wingspan that ranges from 6.5 to 7.5 feet, bald eagles are second only to the California condor as the largest raptor on the continent. Females are actually larger than males, and have a longer wingspan.

4. Regal as they may look, bald eagles are not above theft. Bald eagles often bully their smaller cousins, osprey, out of their freshly caught fish for an easy meal. The National Zoo writes, "Eagles will wait on a favorite perch for an osprey to return to its nest with a fish in its talons for its own young, then harasses the smaller raptor until it is forced to drop its prey for the eagle to retrieve."

5. Bald eagle pairs build some of the largest nests in the world. Pairs work together each season to build the nest of sticks, twigs and grasses. To support the weight of the sizable birds, some nests can be over 10 feet deep, over 8 feet wide, and weigh over 2,000 pounds! While the nests are huge in the first place, bald eagles mate for life and sometimes return to the same nest every year, building on it a little bit each season and crafting the largest nests of any North American bird. According to the Guinness Book of World Records, the largest bald eagle nest on record was found in St. Petersburg, Florida. The nest was 9.5 feet in diameter, 20 feet deep, and was estimated to weigh 4,409 pounds.

Related on MNN: Bald eagle makes the catch of the day