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Sometimes when I'm trying to decide whether the birds of the Cameroon
Mountains of West Africa are the result of one invasion and variation
_in situ_, or of two invasions, or whether the Himalayan red-billed
choughs of Ladak are different from those of Nepal, or how the molt of
the cassowary resembles that of penguins, I am called to the telephone
to identify a bird someone has seen.
The chances are it's a starling. I've not kept a record, but I fancy
half the questions are on identification of starlings. In the distance
starlings are black, and people know them. But close up, where details
can be seen, they puzzle people with their variety. The young may be
dull brownish; the adults may be speckled in the winter; in the spring
the speckled tips of the feathers wear off and they're all black. But
the black is iridescent, and in sunshine glitters purple or greenish.
And the bill color changes too: it becomes yellow in the spring.
Sometimes it's surprising how you can spot a bird from a brief
description. Take this one: a bird that sits with its stomach on
the ground, and has a big mouth, and long whiskers; a whippoorwill
obviously. Or take this one: a bill like a chicken and with flat feet
at the back; obviously a pied-billed grebe.
There was one that absolutely stumped me for a day. The lady said
it had a bill like an eagle, and a tail that stuck up. For the rest
she was vague. Often habits, actions, or habitat are a help to me in
placing a bird, but I could get nothing to help--not even where she had
seen it. I admitted I couldn't help her. The next day someone brought
in a picture puzzle out of a newspaper, and there, right in the center,
was my bird. It was a dodo! We don't mind helping people learn things,
indeed we consider it part of our job, but to help them work puzzles is
too much!
MY LESSON Sight identifications of most students probably contain
errors. On common species it's not important, as quantitatively
they cancel out. But when a bird tripper, anxious to make a new
record, wants me to help him decide he saw an exotic tern, I'm very
careful--I've had experience. Rarities have to be checked on all
points, not identified by elimination or on a few key characters. One
of the best lessons of caution I had in New Guinea. It was in the
mountains. Each morning I hunted in a forest where I'd found a new
genus of bowerbird. Anything might occur, I thought. Then I saw flying
through the treetops what could only be a magpie. A long-tailed, black
and white bird, its pattern was unmistakable. There was nothing like it
known from New Guinea. It would be an extension of range from Asia. Or
it was a new and unknown species. Anyway I needed it as a specimen. But
it was shy and eluded me. Morning after morning I haunted the forest.
Finally I got the bird. And it turned out to be a partly albinistic
specimen of a common, black, long-tailed bird of paradise. The abnormal
white areas in its plumage had fooled me completely. But it helped
teach me caution as to sight identifications.
One of my Gary friends, Mr. Raymond Grow, who is a keen bird student,
has the proper approach, as his identification of a winter duck showed.
There were a number of unusual winter birds that season (1951-52):
brown-headed chickadees, pine and evening grosbeaks, and red-breasted
nuthatches, all from the North, were present. It was the sort of winter
one expects other rarities from the North.
DUCK CAUSES CONFUSION Mr. Grow had seen at the edge of Lake Michigan a
duck he didn't know; it was boldly patterned in black and white, a big
duck. An immature male eider seemed the only possibility. He came into
the museum and we went over specimens, noting the difference in the
shape of the head between the king and the common eider. He studied the
descriptions and the plates. Nothing quite fitted. Unsatisfied, he went
back to Michigan City, found the duck again, and suddenly realized
it was a muscovy duck, partly albinistic, and escaped from someone's
barnyard.
It's not the first time a muscovy has caused confusion. Only a
year or so ago we had a duck sent us from the Philippines that our
correspondent wrote was shot swimming in a river with a Philippine
mallard and surely represented a new species. But it turned out to
be a muscovy whose original home is tropical American but has become
domesticated and transported by man to far parts of the globe.
Occasionally birds escape and take to the wild, even as this Philippine
bird had done.