Photo taken on Sunday via Eagle Cam screenshot. Our story thus far: The Bald Eagles incubated two eggs this season. Both eaglets have hatched. You can view the nest on streaming video here. Will the smaller eaglet get enough food? Are the parents different each year? Once the eaglets are fully grown, do they ever see their parents again? With so many pairs of eyes watching the Duke Farms, questions are sure to arise. For some authoritative answers to viewer questions, we turned to Kathy Clark, eagle expert and a wildlife biologist for the N.J. Endangered and Nongame Species Program. The questions are in italics, indented. Kathy's answers are in roman (the regular typeface).
I've noticed the parents seem to favor the stronger of the two eaglets and not feed the smaller as much. I've read there's a possibility they'll reject the weaker one. Is any human intervention is planned in that event ?
The observer is correct that eagles (and all birds with asynchronous hatching) will feed the oldest and strongest chick first, but that's not the same as "rejecting" a smaller chick. This is an evolutionary adaptation so that in times of scarce food, at least one chick might survive rather than none of them. When food is adequate, all chicks get fed as long as they continue their begging behaviors to the adults.
Are the two parents are "strangers" when they mate?
Depends what you mean by "mate." They spend time together, sometimes even more than one year, leading up to nesting. Many new pairs build a nest but don't lay eggs, when they are in their 4th year and not yet sexually mature. Courtship is an important aspect of their behavior leading up to nesting -- it builds the pair-bond and provides them "clues" as to their potential mate's suitability (ability to nest-build and bring in food). So by the time egg-laying time comes around, the birds do know each other.
Do the same parents return to the nest each year?
The same adults remain in their nest area year-round, and they add to their nest each winter prior to nesting. They are quite loyal to their nest site.
Once babies are grown and fly away, do the parents just say bye-bye and never meet again?
Transmitter being attached to a young eaglet. Eaglet is hooded to keep it calm. Photo courtesy of Conserve Wildlife Foundation.
We don't really know. We've had some visual observations of an adult following a fledgling when it makes some large movements away from the nest, which suggests they care for them until they're sure the young eagles are doing well. But after the young leave the nest area for good (I recommend checking out maps of satellite-tracked eagles like ours at http://www.conservewildlifenj.org/protecting/projects/baldeagle/), and later end up in their old nest area, we can assume they would know each other, but they no longer have that relationship. The tracked bird we named "Nacote" from 2014 has been all over southern NJ, and has been close to his old nest and other nests. Adult birds will defend their nest area from all eagles in most instances. We've heard a report of a young eagle hanging around a nest with 2 adults and appearing to help the adults.... That's not the norm.
Got a question or suggestion? E-mail Jim at firstname.lastname@example.org
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.