Staff from Arizona Game and Fish rappelled down to get to the nest, which has been in the same spot for years; the same adult eagles keep coming back.
To tag the birds, they cover up the talons and put a hood on their heads to keep them calm.
"When we first saw them they were these gray little cotton balls," said Frank Meyer.
Meyer has been watching over the eagles since they hatched. He's part of a group that monitors the birds from below. On Monday, he got to hold one for the first time.
"Kind of completed the circle in a way.. we get to sit over there and watch them, and now we finally get to see them up close," said Meyer.
As their parents circled overhead, the staff checked the birds' health. They won't get those signature white feathers for a few more years.
The experts measured the birds' sharp talons and beaks; they also weighed the birds.
So before they are able to leave, Game and Fish staff attached two tags to the birds' legs. They've been tagging baby Bald Eagles since the mid-1990's.
"We are able to see how long these birds are living. If the life expectancy starts decreasing, or if they are having issues in the wild, we need to spend some time to figure out what the issues are," he said.
While the nest is empty it gives the staff a chance to look at the nest, see what the birds are eating, and clean out any harmful debris.
Once they are tagged, they lower the birds back to the nest, all while their parents watch from afar.
When the weather heats up, the eagles will head north.