About Eagle D1

D1 is a female Bald Eagle and sister (from an earlier clutch) to D14. She hatched at the Decorah Eagle nest in 2011. We determined her gender by measuring her when we fitted her with the transmitter. Female Bald eagles are larger than males. Her size put her firmly in the female category.

We were able to track D1 locally after putting the transmitter on her. The photographs below were taken in the summer and fall of 2011.

D1 Slideshow

About Eagle D14

D14 is a male Bald eagle and brother (from a later clutch) to D1. He hatched at the Decorah Eagle nest in 2012. He was large enough that we couldn't determine his gender by measuring him, so we sent in some down for genetic testing.

We were able to track D12 locally after putting the transmitter on him. The photographs below were taken in the summer and fall of 2012.

D14 slideshow

Video: D1 is fitted with a transmitter

About the Transmitter

The transmitter is made by North Star Science and Technology: http://www.northstarst.com, or check facebook: https://www.facebook.com/NorthStarScienceTechnology. It is a small rectangular backpack that attaches to the eagles via teflon straps. It weighs about 55 grams, or roughly 2 ounces, and is solar-powered. Northstar's website lists the operational life as indefinite, but probably 2-4 years: our eagle biologist had one last as long as seven years.

For more information about the transmitter, please see this blog post.