A few years ago, a graduate student (GS) asked a couple of fellow biologists
to go out to her field sites and help her learn to identify birds by ear.
To protect the reputations of the guilty, I'll refer to the biologists as B1
and B2 (but one of the Bs did have the initials KC). A typical
conversation for the day went:

GS: What is that bird?
B1: A Junco. (GS takes notes.)
B2: A Chipping Sparrow (GS scratches former notes; takes more notes.)
B1: No way! It's too musical.
B2: You're being fooled by the way the sound changes through the trees.
B1: It's a Junco. A chippie song has an abrupt end.
B2: I see it! It's a Junco. (GS scratches more notes.)
B1: You're not looking at the bird that was singing.
GS: What's that other bird?
B1: It's a towhee.
B2: No, that's the Chipping Sparrow.
B1: No. It's trill is too fast to count the individual notes. That means
it's a towhee.
B2: I can count them.
B1: Well, you're too fast a counter.
GS (Who is starting to look a little upset.): What is that bird?
B1: A Red-tailed Hawk
B2: I'll bet it's a Steller's Jay imitating a hawk.

To summarize, a birder is someone who who can identify birds, an
ornithologist is someone who can identify birds with a note of authority in
his voice, and a twitcher is a person who makes the mistake of asking for
help from more than one "expert" at a time.

Kelly Cassidy