Does the red-eyed vireo have red eyes? Yes—but you’ll rarely spot that feature in the field. The eyes look dark from a distance. Freaky. Actually, not really: red eyes are in fact fairly common in the avian world—loons, hello—but most birds aren’t named for them. Baby red-eyed vireos are born, as early as April or as late as August, with dark eyes; the red iris doesn’t develop until at least the first winter.
Eyes aside, these birds aren’t wildly distinct-looking: they’re sparrow-sized and olive-green and white. And they’re hard to see. Males hang out high in the tree’s canopy, females nest in the understory below. But they’re not hard to hear. Red-eyes call non-stop, all day long, up to 3,000 songs every hour. The record for the most number of songs in one day is 22,197, from a bird in Canada in 1952. Males will even sing with their mouths full (of insects). That’s talent! But not everyone appreciates it. The calls are short, high, up-and-down whistles of two to five notes each; some find the singing monotonous, as if the bird is endlessly asking and answering the same question.
Red-eye nests often fall victim to the parasitic brown-headed cowbird
Red-eyes leave for the south by late October. Like all migratory birds, they’re guided by an internal magnetic compass. But research shows that weight seems to influence a bird’s path when it hits the Gulf of Mexico. Fat birds fly across the Gulf; skinny birds stick to the coastline or travel inland. That makes it easier to stop and grab a bite on the road.
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