Last year's chicks at the end of April
Our story thus far Both eaglets hatched toward the end of March, making them both more than three weeks old. You can view the nest on streaming video here. For many Eagle Cam viewers these days, the big question is: What's in store next for the two eaglets?" Larissa Smith with a Bald Eagle she rescued last fall by wading through chest-deep mucky water in a marshy area in Cumberland County, N.J. For answers to this and other pressing questions, we asked Larissa Smith, Wildlife Biologist/Volunteer Manager for Conserve Wildlife Foundation of New Jersey. At about four weeks of age the chicks will begin to get their blood feathers or pin feathers, first appearing on the head and edge of their wings, says Larissa, who has worked with Bald Eagles for the past 15 years. The chicks' new feathers come out wrapped in a sheath that is filled with blood and the blood feeds the feathers so they grow. Eventually, once the feather is fully developed, the sheath will fall off or the eaglet will pull it off and the feather will unfurl. For the next few weeks after the pin feathers emerge, the chicks will have a mixture of down and feathers. At six weeks of age, biologists will band the chicks.
According to Larissa, over the next few weeks the eaglets will learn to tear at food and begin feeding themselves. By eight weeks of age, feathers have replaced much of the secondary coat of down, Larissa continues. One of last year's eaglets, photographed during banding in mid-May. Over the next few weeks after that, the chicks will begin to strengthen their wings by flapping and stretching in preparation for their first flight. They will also start to branch, which means theyll walk out onto branches to perch. Around 11-13 weeks the chick will take its first flight. After fledging, the chicks will stay in the vicinity of the nest for a month or more learning to hunt and fly. What about predators -- like that Red-tail that flew into the nest a couple of years back? Eagle chicks do have predators -- Great-horned owls, raccoons, Larissa says. Other eagles are also a threat and this has been documented on several other eagle cams. The Blackwater Refuge eagle cam in Maryland in 2012 had an intruder eagle attack and kill both two-week-old eaglets.
The eaglets at an early morning feeding yesterday (Tuesday, Apr. 21). Turtle was the main dish. Shell can be seen in the screenshot, middle right. For Larissa, the most amazing thing about the eaglets is how fast they grow. They are almost the size of the adults at six weeks of age. Juvenile Bald Eagles are actually larger in size than full grown adult eagles. This is because the juveniles feathers are longer and thicker than adults. Adult eagle have fewer, shorter feathers which make them more streamlined. Just because the eaglets are full grown does not reduce the dangers. The final stage when the chick leaves the nest is the most perilous. The mortality rate for first year eagles, juveniles, is fairly high since they are just learning to survive on their own. Its thought that the chances of a juvenile eagle surviving its first year are less than 50 percent. That is why its so exciting to get a resighting of a New Jersey banded eagle.
Got a question or suggestion? E-mail Jim at wrightjamesb@gmail.com
Jim Wright writes The Bird Watcher columnist for The Record and the Herald-News. He is the author of four coffee-table books about wild places, and the deputy marsh warden of the Celery Farm Natural Area in Allendale, N.J.