Saturday, November 24, 2012

Bald Eagles in Dungeness National Wildlife Refuge, WA


An adult Bald Eagle patrols its territory along the shorelines of the Strait of Juan de Fuca, Dungeness NWR, WA; 8/4/2012.
In early August I was fortunate to take a day trip to the Dungeness National Wildlife Refuge on the northern shorelines of Washington State. While there, I was able to spot our Nation's majestic Bald Eagle in various stages of growth. Within minutes of hiking up to the ridge overlooking the shore, I spotted a full grown adult (Above) flying along the beach. Unfortunately it didn't fly any closer, as it turned its course away from my vantage point.
Two "baby" Bald Eagles, not yet left the nest, Dungeness NWR, WA; 8/4/2012.
Later in the day, I located a large Eagle's nest built on some dead branches in a Spruce tree overlooking Dungeness Bay. Two young eaglets (Above) were perched on some branches on the edge of the nest. It looked to me like they were old enough to fly and leave the nest, but a local birder who had been monitoring the nest said that they hatched in late June which made them about 6 weeks old at the time. The italicized information about Eagle growth below came from the American Bald Eagle Information website:

"Eaglet Growth - The young birds grow rapidly, they add one pound to their body weight every four or five days. At about two weeks, it is possible for them to hold their head up for feeding.
By three weeks they are 1 foot high and their feet and beaks are very nearly adult size.

Between four and five weeks, the birds are able to stand, at which time they can began tearing up their own food. At six weeks, the eaglets are very nearly as large as their parents.

At eight weeks, the appetites of the young birds are at their greatest. While parents hunt almost continuous to feed them, back at the nest the eaglets are beginning to stretch their wings in response to gusts of wind and may even be lifted off their feet for short periods.

At three or four weeks, the eaglet is covered in its secondary coat of gray down. In another two weeks or so, black juvenile feathers will begin to grow in. While downy feathers are excellent insulators, they are useless as air foils, and must be replaced with juvenile feathers before an eaglet can take its first flight, some 10 to 13 weeks after hatching."

Bald eagles build their nests in large trees near rivers or coasts. A typical nest is around 5 feet in diameter. Eagles often use the same nest year after year. Over the years, some nests become enormous, as much as 9 feet in diameter, weighing two tons. Even when a nest tree falls or a strong wind blows a nest down, the established pair usually rebuilds at or near the site within a few weeks if it is near the breeding season. The nest may be built in a tree, on a cliff, or even on the ground if there are no other options available.
A juvenile Bald Eagle, Dungeness NWR, WA; 8/4/2012.
There was also a juvenile Bald Eagle (Above) hanging around the same area, Juveniles will not reach sexual maturity until four to five years old, at which time they will grow in their white head and tail feathers. The adult (Below) was perched in close proximity to the nest, and was probably a parent to the two young eaglets in the nest, and perhaps even the parent of the juvenile (Above)

An adult Bald Eagle perched close to the nest, Dungeness NWR, WA; 8/4/2012.

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