Sunday, July 25, 2010

Uppie, Whistling-ducks and Learning from a Crow

[The Fish Crows lurk along the dune path near the plover ponds at Cape May Point State Park - because they're after the plover chicks, sometimes anyway. But they're interesting, tame, and allow study as close as you could want. This one's missing greater coverts, revealing the white flight feather bases beneath. What's going on? Click to enlarge photos.]

Instead of tracking down the 2 Upland Sandpipers that tarried for a bit on the edges of the plover ponds and Bunker Pond Saturday, or pursuing the Black-bellied Whistling-ducks on Lighthouse Pond (found again Saturday, no reports from Sunday), I hung out with the Fish Crows as they preened, caught cicadas, and otherwise lived the good life along the dune trail.

[This Fish Crow's outer primaries are worn and tattered, having survived a full year since they were last replaced. The inner 3 primaries on each wing have been replaced (P3 is still growing in), the new ones nice and glossy, shiny and new. P4 is still missing. Primaries are numbered from the inside out, by the way - crows and other corvids have 10 primaries, the outermost reduced in size. They also have 12 tail feathers (called rectrices), but this crow only has 10 - it's molted the inner 2. The truncate tips of the outer tail feathers indicate a bird more than a year old - juv.'s/first years in many species have more pointed tail feathers, without an inner corner at the tip. Corvids molt once a year (except for their first year, when there is another molt to replace juvenal feathers); Fish Crows finish by September.]

No comments: