BIRDS OF PREY: State scientists tag and watch local Bald Eagle nestling

The Haliaeetus leucocephalus, better known as the Bald Eagle, has been a symbol of the U.S., since it was founded over two centuries ago. Now, Arizona Game and Fish is continuing its efforts to grow the Bald Eagle population in the Grand Canyon State.

Game and Fish has recently banded its fifth Bald Eagle nestling this year, as its parents watched from above the nest. These banding efforts help keep track of the bird, and threats to the population.

"We band these nestling Bald Eagles when they're five or six weeks old," said Kyle McCarthy, Bald Eagle Field Projects Manager for Game and Fish. "That's a good time for them, because they're old enough to handle a little bit of stress, but they're not old enough that they're capable of flight yet."

The efforts by Game and Fish employees began in the morning, as they took a boat ride on Lake Pleasant, on their way to the nest. To reach the nest from there on, the team must first hike up a cliff. Once lines are secure, biologist Kurt License rappels down to the nest, and gets the nestling ready for banding.

"I make sure the nestling is secure, and it had a hat over its head to keep it from freaking out, and also had some booties on its talons so it couldn't grab itself or anyone else," said License. "Then from there, I put it into a bag and the bag was raised up so it could be processed up on top of the cliff."

Once on top of the mountain, McCarthy takes over. He, along with two nest watchers, then take blood samples and measurements

"It gives us the chance to assess the health of the bird, and see if it has any defects that need any rehabilitation," said McCarthy.

Then comes banding of the birds.

"It's a blue band that we put on the bird to identify it," said McCarthy. "It's got a unique letter and number combination. It will tell us that the bird was born here at Lake Pleasant in 2017. It will tell us who its parents are, if they're banded or not. It gives us a wealth of information over the course of the birds life."

As the measurement and banding takes place, License is still down in the nest, looking for egg shell fragments. License said the thickness of the egg shells can give an indication as to whether they were exposed to pesticides.

License said he has also found things that don't belong inside the nest.

"Years before, we've found fishing hooks, fishing line, some things that shouldn't be in there," said License. "I didn't find one of those this time so that was great. Some things I did find were crayfish claws, other prey remains like fish, birds."

In the end, the nestling, a five-week-old female, was gently taken back down the mountain, and placed back into the nest. Both License and McCarthy said the one-hour disturbance is important for research and management of the population.

"We can see over the course of time how long these birds are surviving," said McCarthy. "And if not, we can try to figure out why are they not surviving as long as they should and we can identify that threat, we can address it with management action."

Nest watchers Peter Rebholz and Courtney Ross then keeps a watchful eye on the nestling, until it leaves the nest. The two have been living on the lake for weeks, watching the egg, and now, the nestling. For Rebholz, the watch has been surreal.

"We're proud parents as well, I think so," said Rebholz. "A little defensive when people come in, like, 'watch out for our baby'. It's a very cool day."

For Rebholz and Ross, the watch over this particular nestling will end in weeks, as the Bald Eagle nestling will leave the nest when it is about 10 weeks old. As for mating and finding its own territory, that won't happen until it's five years old.

The Nest Watching Program is celebrating its 40th anniversary in 2017.