Tag Archives: Bald Eagles

A Tale of the Tape …. at the Hatchery Nest

January 7, 2019: N2B

by Sherri Elliott The Decorah Eagles nest this morning gives a great look at the depth already this season as DM2 and Mom pause work to track their territory. There are two things I look at every view…a lovely heart shape circled in the bark of the cottonwood tree, as well as the diamond shape in the bark which I have always used as a tape measure. During the N2B starter platform build in 2015 (video here), the bottom of

How much weight can a bald eagle carry?

November 6, 2019: Mr. North and the stick

On November 4th of 2015, photographer Alex Lamine photographed the female bald eagle at Berry College carrying a very large stick, which she dropped. That stick turned out to be 12 pounds! Today, Mr. North dropped a stick of unknown weight, although it was clearly more than he could lift from the ground. How much can eagles carry? We’ve speculated quite a bit about how much weight eagles can carry.  I talked to Professor Jim (Grier has studied birds of prey

Eagle Eyes!

Human Eye versus Eagle Eye

Has anyone ever called you eagle-eyed? Relative to humans, bald eagles have larger, sharper eyes that see further, collect more details, and produce stereoscopic vision to greatly improve depth perception. A bald eagle’s visual acuity begins with its eye size and shape. Dad’s somewhat tubular eyes occupy over 50% of the volume of his skull, as compared with less than 5% in us spherically-eyed human types.  He can voluntarily adjust the curvature of his large cornea and lens (we’re restricted