| We
decided using video cameras would be the best way to study the diet of nesting
Bald Eagles. Bald Eagles can be easily bothered by people coming
close to a nest so cameras are a great way to record information while
minimizing disturbance. Plus, nests are so high in the trees that it
would be difficult for a biologist on the ground to identify what the eagles were eating way up in the nest.
So how did we do it? It took a team of at least two biologists to install each camera. One biologist climbed the nest tree using tree spikes, a climbing harness, and several ropes. Once in the nest, the climber gently put the chick in a bag and carefully lowered it to the ground using a long rope. A second biologist was waiting on the ground below to band the chick. A "band" is a metal ring that fits around the leg of a bird. The band is engraved with a unique number so that researchers we can identify the bird if it is ever caught again. After the band is in place, the chick was then placed back in the bag and hoisted up to its nest. Next, a tiny video camera was installed above the nest. Finally, the climber rappelled down from the nest tree. Which nests? Since we wanted to understand how the diet of Bald Eagles varied in different salinity zone, we chose nests by considering which salinity zone they were closest to. Roughly half of the nests in our study were close to mostly freshwater zones and the other half were near the saltier waters by the river's mouth. Can anyone go up to a Bald Eagle's nest? No! There are government laws that protect Bald Eagle nests and the land around them - especially during the winter and springtime when the birds are nesting. Only researchers who get special permits are allowed to get close to the nest. Please stay away from a Bald Eagle's nest if you know of one near your house. |
