Monday, January 11, 2010

Mission Accomplished

[Adult Bald Eagle, Cohansey River yesterday. Click to enlarge all photos.]

On the heels of a record-breaking Cape May Hawk Watch count of 459 Bald Eagles and the recent discovery of the first Bald Eagle nest south of the Cape May Canal, last weekend's Mid-winter Bald Eagle Survey in southern NJ (coordinated by NJAS) seems likely to also set records. Results for the entire survey are not yet compiled, but I can tell you at least 25 eagles were on the Maurice River and 33 on the Cohansey River (both Cumberland County, NJ), because that's where I was lucky enough to be.

Just as exciting as the numbers were the age ratios. During the DDT years immature eagles were few and far between - indeed, the absence of young birds was one of the warnings that DDT was affecting raptors. The breakdown on the two river systems this year was:

24 adults
13 juveniles (first life year, second calendar year)
2 "white-belly I" (=second life year=third calendar year)
2 "white belly II" (= third life year=fourth calendar year)
4 transition (=4th life year=fifth calendar year)
15 immatures too distant to age exactly

It's easy to be doom-and-gloom about bird populations, but here's one formerly endangered bird that, thanks to efforts by many people, clearly has recovered - mission accomplished! Let's not drop the ball on this particular mission. . .

[2 Adult Bald Eagles running off immatures on the Cohansey River. The upper left bird is a "white belly I," meaning second life year/third calendar year, aged by the white belly (duh) and the uneven trailing edge to the wing. The wing shape is caused by a mixture of older, longer juvenile flight feathers and newer, shorter replaced flight feathers. The other young bird could be the same age or a year older, since it seems to have a more even trailing edge to the wing - i.e. it may have replaced nearly all its juvenile feathers - but given the way it is holding its wings, it is hard to tell.]

Other birds near the Maurice River included a flock of American Tree Sparrows on the west side of the Maurice River Bridge, Common and Hooded Mergansers various places, Northern Pintails at the Maurice River bluffs, and Common Goldenye at Shellpile, along with a zillion gulls that seemed to contain nothing special, but I'd bet there are white-wingeds and lessbacks to be had there. The Cohansey had a similar duck collection.

[American Tree Sparrow, near the Maurice River bridge at Mauricetown Saturday.]

[Common Mergansers have been pushed south by the ice. These bask in the sunset along the Cohansey.]

[Hooded Mergansers became my new favorite bird (until the next one surfaces) during last weeks Cumberland CBC, when I watched a male hoody fly right into the teeth of the 30-50mph wind, turning and twisting against the gusts and crossing the Turkey Point marsh like an F16. This pair enjoyed more tranquil flying along the Maurice River.]

[How cold has it been?]

In other bird news, Tom Reed watched 10,000+ American Robins come to roost at Jake's Landing Saturday night - good luck finding a European rarity in that! Vince Elia had the pretty male Pine Warbler along the Cape May dunes at Saint Peters yesterday - that bird and the flock it hangs with (which includes Red-breasted Nuthatches) moves around the point. The Sandhill Crane was seen yesterday both at Villas WMA by several birders and on Cape Island on Shunpike Road at the pond east of the road by Mike Crewe. Mike will be co-leading this weekend's Cape May Winter Birding Sampler workshop with me - there's still room, sign up now!

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