Mike Smith wrote:

>Dennis, I've given greater thought to the mulit-species hypothesis (that
>the flock represents more than one species), and checked my notes. There
>was a day this spring when I scoped five individuals (25 X 60mm
>Spacemaster) at only about 50 feet. They were at my neighbor's feeder and
>I took notes on each one's plumage. Two had extensive red feathers on the
>head and breast (probably about 10% of feathers were red), and red carpal
>patches. This is the character you consider indicative of
>Crimson-fronted. Two others had limited red feathers (probably 1-2% of
>feathers were red), no red on the underwing, and a small red crown not
>touching the eye-ring. These are characters consistent with
>Scarlet-fronted or Mitred. The fifth had no red anywhere, consistent with
>Green. I was not really considering the possibility that this flock could
>be mixed species, that is I had assumed that they were all descendants of
>two birds, since breeding was noted in your neighborhood. Plus it was
>consistent with somebody losing a pair of birds which then reproduced. Is
>there a pattern of plumage change with age among _Aratinga_? Could the
>reduced-red individuals represent young of the two most colorful
>individuals? With the green one being the youngest?

Immature Crimson-fronted, according to _Birds of Costa Rica_, lack red on
the head and body, although they don't say anything about lacking it on the
wings. According to _Birds of the High Andes_, juv. Scarlet-fronted and
Mitred show little or no red on head. Juvenal plumage should be lost
within a few months, but maybe they were being sloppy or maybe that plumage
is held for a longer time in parrots; I don't know. One of the ones in my
yard a few years ago had no red, indicating (a) a young bird, which was
what I thought at the time, as it looked just like the others otherwise*,
or (b) the same redless bird you're talking about, which would indicate
another species.

*But they all look alike, it seems!

Dennis Paulson, Director phone 206-756-3798
Slater Museum of Natural History fax 206-756-3352
University of Puget Sound e-mail dpaulson at ups.edu
Tacoma, WA 98416