Now that our eaglets are getting their first full set of feathers, we’re seeing a good bit of flapping in the nest as the eaglets build up their flight muscles. Below is a video from April 4 that shows our eaglets in action. At the beginning of the video the older chick gives a couple big stretches, then lines up for a nice slicing (the fancy word for pooping) maneuver. If you watch closely, it clears the branches and hits the ground. (Don’t walk under an eagle nest!) Next our older eaglet gives a nice little flap and shows us his blood feathers or pin feathers. Then he walks over and annoys his little sibling, which is always fun. Finally he uses his big talon to scratch at the pin feathers on his head, which likely itch.
If you check out our younger chick in the video, you can see he has a nice big crop on his chest (recently fed) and then he gives a little flap toward the end of the video, and you can see his blood feathers as well.
An adult bald eagle has around 7,200 feathers. Eagle feathers come in a variety of types, including:
- Primary feathers, which can be spread out like fingers on a hand to reduce drag.
- Secondary feathers, which can be moved down to increase drag or up to reduce it.
- Tail feathers, which are used for steering.
- Coverts, which make the wing thicker in front, so that air will flow faster over the top of the wing.
You can learn more about eagle feathers and flight on the Bald Eagle’s Quest for Flight web page. Also check out the Feather Atlas run by the U.S. Fish and Wildlife Service where you can search on bald eagle and golden eagle feathers and see photo examples.
Speaking of photo examples, below is a nice chart that the USFWS put together showing how bald eagle feathers compare among adult and juvenile eagles. In this collection are two feather types we haven’t mentioned yet — plume and body feathers, which sit closer to the eagle’s body, help give it shape, and provide insulation for warmth.
Bald eagle feathers are valued even today for their use in Native American religious ceremonies. When we find a dead eagle or parts of an eagle at Blackwater NWR, the staff turn them over to the National Eagle Repository in Colorado where the USFWS distributes deceased eagles, feathers, and parts to members of Federally Recognized Tribes for religious purposes. By overseeing the distribution of bald and golden eagle parts, the USFWS helps to ensure the fair distribution of eagle remains and also helps to reduce the black market demand for these items.
In our next blog post we’ll talk about feather molting and preening, which is how our eagles keep their feathers in tip-top shape.