Red-tailed hawks go from egg to flight

On the afternoon of June 7 — about seven weeks and more than a million prying eyes after it hatched — the last red-tailed hawk chick raised on a Weeks Hall window ledge threw caution to the wind and flapped away from home.

That it landed in a tree less than 20 yards away is immaterial. The hawk, tapped as the runt of the three-chick litter by hundreds of thousands of Web cam viewers, left its audience a pile of sticks and bird poop littered with bits of downy feathers.

“I guess I was sort of sorry to see them go,” said Mark Berres, a UW–Madison ornithologist. “But it gave so many people a glimpse into what happens in the nest, and how these birds — which they probably see at a distance all the time in Wisconsin — develop from the egg to flight.”

The three chicks hatched on April 19 and 20, growing from tiny, white babies dependent on their parents into juveniles that at certain angles were hard to tell from the adults. Two hawks began daily sojourns out of the nest a few days before the last one left, teasing an Internet audience that was both excited to see the chicks fledge (leave the nest under their own power) and also disappointed the show was over.

In the end, the live stream from the camera perched about 10 feet from the hawks’ nest was accessed more than 1 million times, according to John Lalande, a Linux systems administrator at the Space Science and Engineering Center in the Atmospheric, Oceanic and Space Science Building next door to Weeks.

“We’re so glad people enjoyed watching it,” said Lalande, who helped install the camera and see to its broadcasting with colleagues Nick Ciganovich of SSEC and Brian Hess of the Department of Geosciences. “Assuming the hawks come back, we’ll be here with the camera next year.”

It is entirely possible there will be another brood in 2013.

“Nobody really understands the reason a bird chooses a nest site,” Berres said. “But the fact that this pair of adults successfully raised three chicks here makes it likely that they will return to this area. Not necessarily to that very spot, but to the area.”

For the rest of the summer the family of five is likely to remain intact.

“For Mom and Dad, this is the next stage of parenting,” Berres said. “They are out there with three fledglings that have to build up their musculature in their legs and wings. They’re going to have to practice their takeoffs and landings and roosting and — most importantly — learn to hunt.”

By watching their parents and trying things out, the three chicks will learn to feed themselves and interact with other birds of prey. In the process, the hormones that help drive the parental feelings will fade from the mating pair, and the group will break up.

“If the area can handle more red-tailed hawks, the young ones are likely to stick around,” Berres said. “The problem is, Mom and Dad have a territory, and they’re likely to actively defend that territory. That’s even more likely after they’ve successfully fledged three young here.”

A powerful attraction to the Weeks Hall neighborhood is good news for hawk cam fans, and even the scientist. Berres checked the camera regularly, watching behavior changes in the parents as the shifted from directly feeding the chicks to providing them with scraps, portions and then fully intact prey animals — rabbits, chipmunks, mice — as the young birds figured out how to use their own hooked beaks and sharp talons.

“When I watch that, I think, ‘Wow! How do they know to do this?’” Berres said. “It must be innate on some level. Those are the things that really interest someone like me, and the things that I’m excited the camera can show to the public.”