Sunday, March 30, 2014

Newborn Bald Eaglet Comes Out Of Its Shell


It's a ... bird. A bald eagle chick hatched Friday afternoon from an egg laid five weeks ago in the nest overlooking the Monongahela River in Hays.
It's unclear if the hatched egg was the first one laid, and the eaglet's sex has not been determined. Two additional eggs are expected to hatch in coming days. Watch it happen live at http://www.pixcontroller.com/eagles/.

Viewed on live video from a wildlife camera focused on the nest, the egg began showing signs of pipping -- pecking from inside the shell -- at 11:05 a.m. Friday. Hatching began at 2:36 p.m.



"We have a hatch," said Bill Powers of PixController, which provided the camera.

By about 4:30 p.m. the baseball-sized eaglet was clearly visible when the mother stood or moved around the nest, the cracked egg still lying near the other two eggs. The male eagle roosted nearby or brought fish to the nest while the female continued incubating the remaining eggs and warming the eaglet with her body.

The hatching marks the Hays eagles' second consecutive reproductive success. They fledged an eaglet in 2013. Eagles enter into "extended partnerships," often until something happens to one of the mates.

The average incubation period for bald eagle eggs is 35 days. This egg hatched in 37 days.

Ornithologist Bob Mulvihill of the National Aviary said while prolonged cold weather could have lengthened the incubation period, it's more likely the hatching occurred at the furthest point of the normal incubation range.

Jim Bonner, executive director of the Audubon Society of Western Pennsylvania, said he isn't so sure. The egg that hatched Friday might not be the first laid. The late timing could indicate that the first egg didn't survive, and it was the second egg that hatched.

"It's right on the cusp. I wouldn't deny that this is the first egg, but I have a tough time saying that definitively," he said.
Eventually more evidence will be available.

"If in time we see two eggs have hatched and one didn't make it, it could be that what we're witnessing now is actually the hatching of the second egg," said Mr. Bonner. "This could be due to the fact that the [first] egg was infertile from the start or that the eaglet died while still in the shell. It's impossible to know without actually physically inspecting the egg."

Audubon communication director Rachel Handel said Friday's hatching occurred quickly, but can take as long as 48 hours from the first signs of pipping to when the eaglet wobbles free of the shell.

"Before the eaglets actually break through the main shell, they break through an inner membrane, and it is possible for the parents to hear the chick from outside the egg," she said. "After the eaglet hatches, it will be wet. It will dry quickly, will be a light gray color, and will appear to be very fuzzy. Its eyes will be brown; skin, legs and lining of its beak will be pink."

The male, slightly smaller than the female and with a distinctive white feather on his right side, will occasionally warm the eggs and the eaglet when the mother temporarily leaves the nest.

"Once all hatching is complete, the young will develop relatively quickly, especially in size," Mr. Bonner said. "They will develop their second down around 10 days old. During the first few weeks one parent, usually the female, will always be at the nest."

The young remain vulnerable. There's a 50 percent mortality rate in the first year for eaglets, which should be ready to leave the nest by the Fourth of July, said Gary Fujak, state Game Commission wildlife conservation officer.

Having protected the nest from a raccoon attack and at least one avian predator, the eagle parents thwarted another attack Wednesday.
"Around 2:30 p.m. a red-tail hawk took several swipes at the male bald eagle while he was on the nest," Mr. Powers said. "The female was quick to respond and chased the hawk away."

Newly hatched chicks are totally defenseless, giving predators the best opportunity to raid. A crow, owl or hawk could snatch a chick and fly off before the eagle parent could react. A raccoon or other predator could take an eaglet easier than it could an eagle egg. When the weather warms, snakes will be a constant threat.

"People should understand this is all totally normal -- it's what happens in every bird nest everywhere all the time," Mr. Bonner said. "It's just that usually we don't have the luxury of looking into the nest with a video camera."

Human interest in the unfolding eagle drama has been high. People from as far away as Holland are watching the live video of the nest provided by the PixController security camera company and state Game Commission, which handled more than 10,000 page views during the hatching. High use resulted in a temporary disruption of the video feed as the chick began to peck through the shell.

The camera will remain in place as long as there is activity in the nest, Mr. Fujak said, adding that the Game Commission hopes to expand the use of such cameras.

Someday, it could live-stream cubs at a bear den, he said.

Kathy Hartos of Dravosburg said her daughter, a teacher, has been regularly showing her fourth-grade class in Delaware the video.
"That camera is like watching National Geographic or Animal Planet," she said.

Early Friday evening she and other eagles' fans -- no, not those Eagles, put your Terrible Towel away -- flocked to the Great Allegheny Passage near Sandcastle to get a different vantage point of the nest perched high on the hilltop. Just visible from the trail, the nest appeared still, save for the moment when an eagle would swoop in.

Mr. Fujak said he cleared his plans Friday night to be there -- separated from the nest by hill, highway, scrap yard and train tracks. The noise and human presence doesn't seem to bother the nest residents, he said.

"Wildlife changes and makes adjustments," Mr. Fujak said. "... With the exception of the trains, cars and humans, this is a good habitat for eagles."
The eagles could continue returning to this nest for years to come, he said.

The nearby river provides the eagles with fish, though eagles will eat ducks, rabbits and squirrels, too. Hopefully, he said, a stray cat doesn't wander too near the nest.

"There could be some things happening in the nest that aren't warm and fuzzy," he said.

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