Showing posts with label Cackling Goose. Show all posts
Showing posts with label Cackling Goose. Show all posts

Saturday, January 28, 2012

Cackling Goose

Cackling GooseRidgway's Cackling Goose, Hillsboro, Oregon, 10 January 2012 by Greg Gillson.

 

Still having trouble telling Cackling Geese from Canada Geese? You'll want to revisit last year's post: Greg's white-cheeked goose rant... I mean, primer.

And don't forget this great resource (pdf): Identification Field Guide to the Geese of the Willamette Valley and Lower Columbia River by Kelly Warren for the Oregon Department of Fish and Wildlife.

Friday, February 18, 2011

Greg's white-cheeked goose rant... I mean, primer

Can you tell the difference? A pair of long-necked Canada geese with their chicks among short-necked Cackling geese. The Cackling geese are just getting started on their migration to the Arctic to breed, while these Canada geese have already had success locally! Fernhill Wetlands, Forest Grove, Oregon on 22 April 2006 by Greg Gillson.

 

Empidonax flycatchers, small sandpipers, immature gulls, female hummingbirds,... All these are notoriously difficult to identify. However, there is another abundant taxon that is proving to be surprisingly difficult for many birders to identify accurately on a day-to-day basis.

In 2004 the American Ornithologists' Union split Canada Goose into two species, creating the name Cackling Goose (Branta hutchinsii) for the smaller forms and keeping Canada Goose (Branta canadensis) for the larger forms.

As a reviewer for eBird, it seems that most birders still do not know how to separate them. What I see happening is that a birder will identify a few Cackling geese, and then lump all other geese they see that day into the catch-all "Canada Goose."

As you can see from the above photo, the larger resident Western Canada Goose is 45 inches long, while the smaller migrant Ridgway's Cackling Goose is only 25 inches long--barely larger than a Mallard. The Cackling Goose is named for its high-pitched yelping calls. The Canada Goose gives the stereotypical deep honking call.

I don't want to over-simplify (because this is a very complicated situation) but 80% of the time it is pretty much that easy. Big or little.

Yes, it is true that there are at least 3 races of Cackling and 4 races of Canada Goose in western Oregon. Yes, the largest Cackling (Taverner's) is very similar to the smallest Canada (Lesser). But, frankly, if you don't spend time with a spotting scope carefully analyzing these intermediate birds, then the proper label for eBird (and your personal list) is "Cackling/Canada Goose."



There is nothing wrong with listing 25 Cackling Goose, 50 Canada Goose, and 600 Cackling/Canada Goose on your list. In fact, such honesty and accuracy is praiseworthy.

In western Oregon it is unusual to see more than a couple hundred Canada geese at one location. Most of these will be the big resident honkers, the white-breasted Western Canada Goose. At the Willamette Valley goose refuges you may see 1000 of the dark-breasted Dusky Canada Goose, but the entire world population of this form is perhaps only 7000 individuals. There may be a few Lesser Canada Geese mixed in.

The tiny, dark-breasted Ridgway's Cackling Goose is an abundant migrant and common winter visitor in western Oregon. Taverner's Cackling Goose is common in winter.

As an eBird reviewer for northwestern Oregon, I expect to see perhaps 100 Canada Goose and 5000 Cackling Goose on your non-summer lists, as typical. At Finley NWR, near Corvallis, Oregon, maybe 1000 Canada Goose and 7000 Cackling. Do you see that, in general, I expect 7-50 times as many Cackling geese as Canada geese? How does that compare with what you are reporting?

 

Cackling GooseDo you recognize that these are Cackling geese, and not Canada geese? Forest Grove, Oregon, 10 October 2009 by Greg Gillson.

 

East of the Cascades, in the Great Basin, I expect more Western and Lesser Canada geese and fewer Cackling. But I am uncertain of the exact ratios and seasonality there. But don't expect eBird to help, as the reports of these two species is all mixed up. And reports before 2005 will all be Canada Goose.

The big challenge is Taverner's Cackling Goose and Lesser Canada Goose. I think that Sauvie Island, Oregon and Ridgefield refuge, Washington, are probably the locations where these similar forms are most equally-common. Perhaps also Klamath Falls area. If anyone of you knows, please leave a comment.

Here are the scientific names of the white-cheeked goose forms mentioned in this post. These are the most-likely forms to be found in the Pacific NW. They are listed generally from largest to smallest:
Western Canada Goose (Branta canadensis moffitti)
Dusky Canada Goose (Branta canadensis occidentalis)
Lesser Canada Goose (Branta canadensis parvipes)
Taverner's Cackling Goose (Branta hutchinsii taverneri)
Ridgway's Cackling Goose (Branta hutchinsii minima)

 

Cackling GooseCackling geese have short necks, the dark breast indicates these are the abundant Ridgway's form, Forest Grove, Oregon, 17 October 2008 by Greg Gillson.

 

Largest and smallest, and both most-likely of all the forms: Western Canada Goose facing left, Ridgway's Cackling Goose facing right. Notice how the wing tips extend far past the tail on the Cackling Goose, but the wings are shorter on the Canada Goose. Hillsboro, Oregon, 31 December 2010 by Greg Gillson.

 

Ridgway's Cackling Goose are barely larger than Mallards. The rightmost goose is slightly larger with more sloping forehead and longer bill and paler breast and may be Taverner's Cackling Goose, Hillsboro, Oregon, 31 December 2010 by Greg Gillson.

 

I hate not being able to put a name on a bird. But, frankly, I still don't know whether this flock of 300 geese are Taverner's Cackling Geese or Lesser Canada Geese (or something else, or both). They go down on my list as "Cackling/Canada Goose" or "white-cheeked goose (species)" or "Canada-type Goose," but not "Canada Goose." The small out-of-focus goose in the back with purplish-brown breast facing left is Ridgway's Cackling Goose, Hillsboro, Oregon, 31 December 2010 by Greg Gillson.

 

If you are interested in pursuing this more thoroughly, you may start with Harry Kruger's page.

We've discussed these geese previously in At the pond... Canada Goose and At the pond... Cackling Goose

Monday, January 25, 2010

At the pond... Cackling Goose

Cackling GooseCackling Goose, Beaverton, Oregon on 17 February 2009 by Greg Gillson.

 

In July 2004 the American Ornithologists Union officially separated the small forms of Canada Geese. They called these smaller white-cheeked geese the Cackling Goose Branta hutchinsii. The larger forms retained the name Canada Goose Branta canadensis.

We have already discussed the larger Canada Goose.

Cackling Geese form the majority of the large flocks of fall and spring geese west of the Cascades and in the Central Valley of California. In past years the population primarily migrated through the Klamath Basin and wintered in the Central Valley. In recent years a growing portion of these geese have been finding conditions in NW Oregon and SW Washington suitable for their wintering grounds.

In general (and there is considerable variation among many forms in the Pacific NW), Canada Geese are larger, with longer necks, and honking calls. In contrast, Cackling Geese are small (some as small as domestic Mallards), with short necks, and high-pitched yelping calls.

Standing or swimming the wing tips fall short of the end of the tail on Canada Geese, while the longer wings of Cackling Geese extend well past the tip of the tail. The dividing line between the smallest form of Canada Goose (Lesser subspecies) and larger Cackling Goose (Taverner's subspecies) can be very confusing. For those wanting to tackle this challenge, please see John Rakestraw's article on Lesser Canada Goose as well as Sibley's guide to birds.

The Aleutian Goose Festival is held each spring in Crescent City, California. It is now transformed into the California Redwoods Bird & Nature Festival, May 7-9, 2010. This form of Cackling Goose is recovering from a severe population decline.

Monday, November 23, 2009

At the pond... Canada Goose

Canada GooseWestern Canada Goose, Hillsboro, Oregon on 6 December 2008 by Greg Gillson.

 

Everyone knows the Canada Goose. Everyone except birders, that is. Why do I say this?

Birds of Oregon: a general reference (2003, Marshall, Hunter, and Contreras, editors) lists 8 subspecies of Canada Goose found in Oregon. Some birders attempt to identify these field identifiable subspecies, or races, when they can. Other birders, however, pay no attention to subspecies, as they can't count them as a separate species on their life list. And, well, many birds are just really hard (or impossible) to pin down to a subspecific identification. So why bother?

Well, surprise! The American Ornithologists Union (A.O.U.) recently "split" the Canada Goose into two separate species. The larger birds, some almost the size of swans, are still called Canada Goose, Branta canadensis, while the smaller geese, some the size of city park ducks, are now called Cackling Goose, Branta hutchinsii.

While your friend who knows next to nothing about birds confidently identifies the overhead skein of birds as "Canadian" Geese, you're not so sure anymore.

Cackling Geese cackle, of course, while Canada Geese honk. That's just a sweeping generality, as there seem to be several "tweener" populations that are very difficult to tell apart. In general, Cackling Geese have short necks, stubby little bills, and wing tips that extend well past the tail at rest.

The resident Canada Geese, the ones in city parks and wetlands that lead goslings around in April, are the Western Canada Geese. They are very large, have white breasts and long necks and bills. The bird in the photo above is a Western Canada Goose.

In winter, we are visited by the smaller, white-breasted, Lesser Canada Goose from the north. These are more common east of the Cascades than west.

And, in the Willamette Valley of western Oregon winters a dark breasted Dusky Canada Goose. The Vancouver Canada Goose is very similar. Some of these winter along the coast, as far south as the Nestucca National Wildlife Refuge near Pacific City, Oregon.

The Giant Canada Goose is a bird of the Great Plains that has been introduced widely in North America. There is an introduced resident population on the Lower Columbia River near Astoria, Oregon. Many of these released birds bred with the abundant local resident Western Canada Geese so that most birds here and elsewhere in the Pacific NW showing "Giant" field marks (white foreheads and larger than the Western race) are probably not pure.

I'll write again about the Cackling Goose later this winter. The main identification challenge is separating the Lesser Canada Goose from the Taverner's Cackling Goose. A good article on this is John Rakestraw's blog on the Lesser Canada Goose.