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No, not which geese are fastest! We mean the different types or subspecies of Canada Goose (Branta canadensis). These subspecies are most often distinguished by size, but as you'll see from our pictures of local "little honkers," what you see isn't always what you get. There are about 11 recognized subspecies of Canada Goose in North America. The most common in Dearborn is the Giant Canada Goose, or B.c. maxima. This largest of the races was extinct in much of eastern North America, and in Michigan, at the turn of the 20th century, wiped out by hunting and habitat destruction. Aggressive reintroduction campaigns resulted in the surplus of these big, non-migratory geese we see today. This is the subspecies that nests in Dearborn.
Now look at this little dingy-breasted goose, shown in these two pictures
with one of her two B.c. interior Jim explained to me that all the geese breeding on the island are considered B.c. interior. This goose was banded on the north shore of the island, where the geese are smaller than other interiors due to low food availability. The habitat has been degraded over the last two decades by high densities of nesting Canadas (seven times higher than on the nearby mainland and up to 300 times higher on the north coast of the island), use by migrant Brants (another type of goose), and especially increasing numbers of migrant and nesting Snow Geese. Eggs of these birds when raised in captivity grow to "normal" size like their mainland counterparts. Therefore, one should use caution assigning subspecies to varying sizes of Canada Goose seen in this region. For more information on this very interesting phenomena, please see
a paper Leafloor and his colleagues published in
the respected journal The Auk (Leafloor, J.O., C.D. Ankey, and D.H.
Rusch. 1998. Environmental effects on body size of Canada Geese.
Auk
115:26-33).
Update: In 2004, the 45th Supplement to the American Ornithologists' Union Check-list of North American Birds split Canada Goose into two separate species: the larger forms remain Canada Goose (Branta canadensis) while most of the smaller forms are now Cackling Goose (Branta hutchinsii). Thus, we can provisionally add a new species to the Dearborn checklist, and the matter of distinguishing between resident Canada Geese, migrant Canada Geese including runts, and Cackling Geese becomes more important. Many people are calling any small Canada Goose
a Cackling Goose, which may very well be jumping the gun. The web
sites listed below offer many excellent identification tips and photos
to study. You should note a few things:
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During
spring and (especially) fall migration, Giants are joined by the slightly
smaller, somewhat darker-breasted migrant race B.c. interior.
Around the UM-Dearborn campus, many geese wearing orange neck collars can
be found in the fall. These birds have been banded on Akimiski Island,
Nunavut, in James Bay (while closest to Ontario, all islands in James Bay
belong to Nunavut, formerly Northwest Territories). One neck-collared
goose was seen by us in the fall of 1995 and again in the fall of 1998.
It was originally banded in 1990 on Akimiski!
There
are other even smaller races of Canada Goose than B.c. interior.
An example is this goose, photographed by Jim Fowler, Jr. at Greenfield
Village on 25 Oct 93. Notice the pale breast, and small size compared
to the nearby Giants. This was probably B.c. hutchinsii (a.k.a.
"Richardson's Goose"), the smallest of the pale-breasted races. They
nest in the northern portion of Hudson Bay.
buddies that she hung around with from late September until early October
1998 on the UM-Dearborn campus. This goose had a regular leg band
and a colored leg band. As it turns out, she was banded as a young
female not yet able to fly on 15 Jul 98 on...Akimiski Island! Since
none of the small, dark-breasted races are known to nest in this part of
Canada, I contacted the person who bands on Akimiski, Jim Leafloor of the
Ontario Ministry of Natural Resources, for more information.
