New goose springs from familiar flock
There is a fairly new imposter in our midst going largely unnoticed. For a long time the Canada goose (Branta Canadensis) has been recognized as representing many different subpopulations. Variability within the species (including size, appearance, nesting areas, voice) is considerable enough to produce as many as 30 different subspecies, in the opinion of some.
The governing body of bird science in this country is the American Ornithological Union, or AOU. Every few years the learned folks in this elite group update recent scientific findings and issue a checklist representing current thought. In 2004, the checklist included an anticipated change to the Canada goose complex. With genetic and other evidence, the AOU split off the four smallest goose populations from the rest and granted them their own species and name: cackling goose (Branta hutchinsii).
In general terms, the cackling goose is a diminutive bird that breeds in the tundra of the far north from Hudson Bay to the Aleutians. By contrast, the Canada goose occupies most of the continental U.S. and southern Canada. Of the four populations of cackling goose, the one which breeds the farthest east - thusly the one we encounter locally during spring and fall migration - is the Richardson's race. This one winters in Texas and Mexico. The other three are largely Pacific in their travels and stick to the west coast or near interior.
For the general populace the new species flies under the radar, being just another Canada goose, albeit smaller. For bird watchers, this means a chance to add another bird to their treasured species lists, and a challenge to learn the differences between cackling geese and Canada geese.
But what does it mean to hunters? Not too much it seems. Dean Riemer, West Fargo, has feet firmly planted in both arenas being, at once, an accomplished birder and an avid hunter. "I know a few people who shoot them because they are different," said Riemer, "but most prefer larger geese because they are a bigger target and have more meat."
While not addressing the new species by name, The N.D. Game and Fish Department vaguely includes the cackling goose in its 2007 proclamation by defining Canada goose as "all Canada geese and any other geese except white-fronted geese and light geese."
The Department, in concert with the U.S. Fish and Wildlife Service, has made changes to the hunting season to better manage the different populations. N.D. Game and Fish biologist Doug Leier said, "We've adjusted the days of our early September Canada goose hunt to more accurately impact the resident giant Canada geese (the largest of the subpopulations) and less so the migrating subspecies."
Identifying a cackling goose is not a slam-dunk, as one might believe. The variability within the Canada goose populations bring them very close in size, in some instances, to the smaller cackling goose. The subspecies, lesser Canada goose, is the one that nearly overlaps the cackler.
Bill size may be very helpful. Our resident Canadas sport a large, sloping head and long bill in the fashion of a swan. Cacklers have a small, stubby, triangular bill reminiscent of Ross's goose. Caution: there appears to be overlap in bill size between lesser Canadas and cacklers.
Overall body size can be a clue too, with the caveat mentioned above. The giant Canadas that live and breed here in the summer dwarf the migrant cacklers by a factor of about four. In fact, cackling geese are nearly the same size as mallard ducks.
Voice might be another good indicator. The deep "h-ronk" of our resident birds is quite commonplace. Cackling geese, however, emit a high-pitched, squeaking cackle; something easily noticed while flying overhead.
Armed with a few of these clues, challenge yourself to find a group of cackling geese among flocks of mixed Canadas. They are a different bird according to the experts. And, as Riemer said, "the little ones are just cool looking birds."