Tuesday, April 14, 2020

Mother Eagle

Since my childhood, I have been enamored by our national bird, the Bald Eagle.  I have memories of seeing them in several zoos and notably, Busch Gardens. I watched the local WVEC Eagle Cam  from Norfolk Botanical Gardens for many years as an adult and I grieved with thousands of people worldwide when the nesting female Eagle was killed by an incoming flight at Norfolk International Airport in 2011.
Beginning in 2018, I was fortunate to be able to watch nesting Bald Eagle pairs at several local nests in Virginia Beach as a Virginia Master Naturalist volunteer for the Virginia Bird Breeding Atlas. The most visible one is located on Honey Bee Golf Course and can be viewed from a public residential street. These Bald Eagles are perhaps the most observed Bald Eagles in Virginia, thanks to social media and local media outlets. Sadly, this nest failed in 2018 when the eggs in the nest were destroyed and the female eagle was injured by an intruding Bald Eagle, while she was incubating. The eggs were just 2 weeks away from hatching.
I was told by my Bald Eagle mentor, Reese F. Lukei, Jr. of the Center for Conservation Biology at William & Mary, that a second clutch was possible, but it didn’t happen. I watch the pair at Honey Bee for about 6 weeks following the nest failure and although the male brought in a few sticks, they did not renest and eventually left the area for a time. But, it was during this time that I was able to identify the female from the male. This particular pair is quite identical!
The following year, 2019, the nest successfully fledged its first two eaglets! It was quite exciting to be a small part of this success story! The parents were great parents! It was this season that I really was able to focus on the Bald Eagle female, who I began to privately think of as “Mother Eagle.”
I believe that Mother Eagle approves the nest location and substrate. This nest had already been built by a previous resident male Bald Eagle (banded Bald Eagle “HK”), beginning in 2013 in a very large Loblolly Pine Tree, a typical site for eagle nests in Virginia. In my opinion, he never acquired a mate at that location and eggs were never laid there. That eagle was struck and killed by an automobile in 2017, leaving the nest vacant for a new pair to claim, which they did with weeks of HK’s death.
The key to identifying male from female eagles is size. The female in the Chesapeake Bay region is typically 1/3 larger than the male. This is called reverse sexual dimorphism. Additionally, their beak depth and talon length are longer. I’ve found if they are perched side by side, it is a lot easier to tell them apart!
My observations include the male bringing in most of the nest material while the female does the “arranging.” After eggs are laid, Mother Eagle does most, but not all of the incubating. She also stays on the newly hatched eaglets for about 2 weeks after hatching, as they don’t yet have enough feathers to stay warm. The male brings in food and I have seen them both do the feeding but also occasionally she has not allowed the male to feed, even blocking him from the nest! It’s clear who is in charge and it’s Mother Eagle!

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