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Thursday, February 4, 2010

Wildwood Eagles + Negative Data

[This pair of Bald Eagles was along Wildwood Blvd. between the George Reading Bridge leaving Wildwood and Rio Grande. They were on the first of the three Osprey nests on the right just before the entrance to the parkway at Exit 4. Photographed this morning by John Steiger.]

Eagles, eagles everywhere, even without an eagle festival. We'll see them for sure on the Wintering Hawks, Eagles and Owls workshop February 13-15 ( follow the link and scroll down to the workshop list), which has only four openings left.

This morning I walked the North Wildwood seawall overlooking Hereford Inlet, which was unusually sparse in the bird department compared to my last visit. Less than 10 ducks, less than 5 loons, less than 10 Sanderlings, only 1 Black-bellied Plover and that was a flyover, not even 50 gulls. Negative data is still data, so you have to ask about the scarcity, what's up with that?

The best explanation is probably the tide, in this case low tide, which means birds in the coastal system could go wherever they wanted to roost, probe, or find a shallow dive to food. Or maybe food is depleted in Hereford Inlet, so the birds are feeding elsewhere.

An alternative explanation is simple math: in North America, wildlife populations reach their low ebb in late winter/early spring, since no new animals are being recruited (born/hatched) and they've been dying since last summer. Annual mortality in birds is startling high, especially for young of the year, exceeding 75% for first year birds in some species.

A lone American Pipit foraged in a melted patch on the dunes, and an "Ipswich" Savannah Sparrow sat atop some bayberry bushes giving its flight note, which seemed to be "thicker" - more modulated or buzzy) and less descending than a "normal" Savannah's seep. Seemed. This flight call bit is sometimes splitting hairs. You only hear a few calls at a time in winter, so it's a good time to practice.

The other landbirds of interest were robins in periodic waves coming from North Wildwood (or offshore?) and flying northwest, maybe 1,000 in total. What they were doing, I don't know.

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