I'm posting a snippet of a conversation I found quite interesting from the
ID_FRONTIERS list serve regarding a Richardson's Cackling Goose in New
York's Central Park. The email is from Peter Pyle, but he is quoting
Shaibal Mitra. (the Central Park bird was considered a possible B.h.
parvipes "Lesser" Canada Goose, mainly due to its bill size, but is now
considered a Richardson's Cackling Goose)

"I think people's idea of what a 'standard-issue' Richardson's Goose looks
like has been skewed by its perceived rarity, so that the smallest, most
extreme individuals have been reported/ identified disproportionately in
our region. On LI, we have often found obvious (= extreme) Richardson's
Geese in the company of somewhat larger but otherwise essentially identical
individuals.

Data from the breeding grounds show that male Richardson's Geese, while
smaller than Canada Geese, are by no means always tiny. I have argued that
the conservative approach to larger-than-expected birds showing the
characters of this taxon in our region is Richardson's until proven
otherwise. That is, the burden of proof has shifted to those who suggest
that parvipes Lesser Canada Geese occur at all regularly in our region."
...
Richardson's Geese have long wings in proportion to their body size.
At rest, the peak of the back rises close to the front end of the body
(often in a distinct little hump), then drops back in a long straight line,
or even a slightly concave line, through the relatively long (usually pale)
tertials. Furthermore, the tertials account for a larger proportion of the
length of the dorsal contour.

In contrast, in Canada Goose, the dorsal contour is better described as a
hemispheric dome, peaking farther back, at the middle of the body, and
appearing evenly rounded."

This little tidbit may be of great help with some of the smaller
white-cheeked geese we get in Ohio, and it makes me wonder how many
larger-than-expected Cackling Geese go unidentified each year.

Good birding,
Andy Sewell
Columbus, Ohio

______________________________________________________________________

Ohio-birds mailing list, a service of the Ohio Ornithological Society.
Please consider joining our Society, at www.ohiobirds.org/site/membership.php.
Our thanks to Miami University for hosting this mailing list.


You can join or leave the list, or change your options, at:
listserv.miamioh.edu/scripts/wa.exe?LIST=OHIO-BIRDS
Send questions or comments about the list to: [log in to unmask]