Dozens of eider ducks, cormorants and guillemots have all been found with contaminated plumage.
The Academy relied, however, on assigning birds to breeds by characteristics such as plumage.
After many a flap (see article), EMU eventually metamorphosed into a bird of much grander plumage.
However, plumage, size and shape were primarily used to identify species until the late 1970s when vocalizations were added.
"Think of a peacock, " he went on, referring to their psychedelic plumage.
The first group had their plumage colour enhanced with a marker pen.
ECONOMIST: Male birds cannot afford to relax their standards
With incremental execution, the dance's signature flipped-up-and-back flexed-leg-and-foot pose looked less like a kicked up heel than a pretty and preened piece of plumage.
Another colourful resident is the wild peacock, found walking around San Pedro's residential areas alerting neighbours to its presence with eerie cries and exuberant plumage.
After studying the Northumberland bird's plumage on hours of videotape and a number of photographs, experts decided the bird was less than one year old.
The result was that the males who had had their plumage enhanced fathered a higher proportion of the clutches in their nests the second time round.
ECONOMIST: Male birds cannot afford to relax their standards
Moments later, Ace appears from the brush and drops what has to be one of the world's prettiest gamebirds--with its red, green and white plumage--right at Arnold's feet.
"It's probably a chicken feather dyed to make it look more exotic than it actually is, " she stated nonchalantly, her interest in plumage apparently falling within the more normal range.
Each "island" developed its own idiosyncratic plumage and song.
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If that happens, it might present problems for some emperor colonies if the seasonal ice starts to break up before fledglings have had a chance to acquire their full adult, waterproof plumage.
Intriguingly, that did not apply to birds that used melanin, another pigment, in their plumage, nor to those that employed iridescence which is a result of the structure of feathers, rather than their chemistry.
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When offered a choice between two males of their own species, one of which came from the overlap zone and one of which did not and thus had the primitive plumage females of both species consistently preferred males from the overlap.
There are few greater thrills, especially in your dotage, than spotting a bird you've never seen before, the effort you put into remembering its plumage and behavior, and then consulting your birding guide and being able positively to identify it.
Half-asleep, I shuffled to the canopy-level observation deck of my rustic wooden cabin, grabbing binoculars and Tito Narosky's "Birds of Argentina and Uruguay" just as a flurry of yellow plumage transformed into what locals term the "banana toucan, " a rare and striking saffron toucanet.
It was the one fixed point on a vacillating compass of relative morality until, one day, a tiny bird, the merest wisp of red plumage, tore away my comforting absolute and aligned me squarely with the NRA supporters, Second Amendment defenders and pro-gun crusaders I had reviled.
Although he cannot definitely rule out a direct effect by the pollution on the birds' metabolism of the yellow pigment, or its incorporation into their feathers, the correlation between a shortage of caterpillars and faded plumage is strong evidence of a link between pollution, diet and bird colour.
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