The Lure of Bird Lores
An avian field mark that warrants special attention this time of year is the color of a bird’s lores — the area between a bird’s eye and bill on both sides of its head. In some birds, especially wading birds, lores change color quite dramatically during the breeding season.
Because birds can see blue, green and red (like humans) as well as UV light, and because the change takes place just as the breeding season begins for birds, the change in lore color, often to a more vibrant hue, is thought to play a part in attracting a mate. (The bills, legs and feet of some birds also change color at this time.)
At the height of the breeding season, Great Egret lores go from yellow to an emerald green. Green Heron lores turn from a yellowish-green to a bluish-black. Snowy Egrets (pictured) lores become bright pink. This happens to both sexes ever year.
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