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ARTICLES ON HAWAIIAN BIRDS AND BIRDWATCHING

Aleutian Canada Goose back from the brink.

The once-rare Aleutian Canada Goose (Branta canadensis leucopareia) has returned from the brink of extinction and is now thriving, thanks to United States conservationists. The United States Fish and Wildlife Service has formally announced that the goose is to be removed from the list of threatened species in need of urgent protection. The species was one of the first that was designated by the U.S. Fish and Wildlife as endangered. The Species is found only on the Aleutian Islands in Alaska, mainly on Buldir and Amchitka Islands.

In 1996 only 800 individuals were estimated as surviving in the World, but after better protection of their breeding and wintering grounds, as well as important migration routes and predator control, the species numbers rose to 6,300 in 1991 and was downlisted from endangered to threatened, the species now numbers 37,000 - more than four times the original target number.

LaVerne Smith, the assistant regional director of fisheries and ecological services said " The comeback of the Aleutian Goose is an incredible success story considering the vast area that the geese use throughout the year and the remoteness of their breeding grounds".

It is believed that foxes which were introduced in the 18th century for fur-trapping, preyed on the geese over the following centuries and resulted in a disastrous decline in the population.

Since 1967 biologists have been eradicating foxes which also benefited other bird species.Conservationists have also been helping to recover the species wintering grounds and improve their attraction and habitat, which are on the west coast of the United States. The majority of the Aleutian Canada Goose population winters in the Central Valley area of California, where 60 per cent of the waterfowl in the north-eastern Pacific spend the winter period. The entire area has been under severe threat from wetland loss and only 5 per cent of the valley's original area remains intact, making the area even more critical for the species which rely on it. Intensive conservation measures in California and Oregon have helped to slow wetland loss in the migration and wintering areas of the geese (Morgan 2001).

The U.S. Fish and Wildlife Service in partnership with the pseudo-conservation-hunting organisation Ducks Unlimited, has helped to restore important lakeland areas in the valley, as well as helping to unite landowners and government agencies.

"Protecting the wintering habitat is crucial in the long-term recovery strategy", said Fritz Reid, the director of conservation planning in the western regional office of Ducks Unlimited.

So what does that mean for birders in Hawai'i?

Canada Geese are annual winter migrants to the Hawaiian Islands in small numbers, with groups usually consisting of two or three individuals, although larger groups have been reported as well. Most that occur are of the smaller races, originating from Alaska and north-western Canada, with some no doubt originating from the Aleutians. The dramatic rise in numbers in the Aleutians (and elsewhere) can only help to improve the number of individuals that might turn up here, especially if the population increases to grow and the amount of available habitat on the mainland decreases. Of course once the birds are here it is a question of whether there is enough suitable habitat in Hawai'i to sustain more than a few individuals over an entire winter period!

Identification of individuals is easy but assigning them to a particular race can be more problematical, although often possible. Hybridization does occur, especially in those forms that have been moved for conservation reasons to areas where another form already exists, but these often resemble one of the parent forms, rather than being intermediate between the two. However, in other geese (eg. Bean Geese) there seems to be that despite occasional hybridization there is not widespread integration (Burgers et al. 1991).

Madge and Burn (1988) state that 'some taxonomists have suggested that the species could be split into up to four species, and it is true that the smallest tundra-breeding high-Arctic forms not only appear quite different, but also sound different. The presence of intergrading zones between a number of races, however, lends much weight against these proposals. In some cases, as in the form taverneri, there is an intergrading link between small and dark minima, large and dark occidentalis and pale parvipes'.

Eleven distinct forms of Canada Goose are generally recognized (Delcour 1954).

DISTINCT FORM COMMON NAME BREEDING LOCATION WINTERING LOCATION IDENTIFICATION FEATURES

canadensis Canada Goose (nominate) SE Canada & NE USA. Atlantic coast USA. Large size, long necked. Black neck with white chin strap. Body buff with paler underparts. Second largest form.

hutchinsii Richardson's Canada Goose Arctic Canada. Gulf coast of Texas and Mexico. Small and dumpy with a square-looking head and short bill. Often short-legged. Can appear silvery - colored at distance. Smallest of the pale forms.

interior Todd's Canada Goose Area south and east of Hudson Bay, Greenland;
NE Manitoba. South-eastern USA; North-eastern seaboard of USA;
Texas. Large with very long neck and long, shallow bill.

parvipes Lesser Canada Goose Arctic Canada west to eastern Alaska. Southern USA, chiefly interior California, but also east to Gulf coast and south into Mexico. Small-medium sized. Long bodied, proportionately shorter necked. Neck can be kinked. Medium bill. Round headed.

taverneri Taverner's Canada Goose From the Mackenzie River westwards. Western seaboard of USA from Washington to northern California. Smaller and darker than Lesser with more compact head and bill. Often shows dark throat line.

leucopareia* Aleutian Canada Goose Some Aleutian Islands. Central California. Very small with tiny deep-based bill. Slightly paler than other western forms. Usually a fairly prominent neck-ring.

fulva Mainly resident coastal British Columbia north to south Alaska. South to northern California. Large, uniformly dark rufous.

occidentalis* Dusky Canada Goose Coastal southern Alaska. Vancouver and Oregon. Darker and smaller than fulva, with shorter & deeper bill and usually lacks neck-ring.

moffittii Great Basin region of NE USA & SW Canada, east of the Rockies. Western USA. Much as maxima but with shorter body and shorter bill and legs.

maxima Giant Canada Goose Great Plains of N. USA. Mostly resident in breeding areas. Largest race with longer neck and bill but similar in color to canadensis, but usually paler.

minima* Cackling Canada Goose Coastal western Alaska. Interior California south to northern Mexico. Smallest form with short neck and tiny bill. Darkest form of all - most are dark-breasted, but some pale. Can exhibit in ideal conditions, a smooth waxy-looking lilac-tinged body plumage.

Those marked with * have been recorded from Pacific Islands (Hawai'i and southwards). Id. features based on information from Batty & Lowe 2001; Millington & Gantlett 1999; NGS 1999; Ogilvie and Young 1998; Richards 1999.

It should be noted that this article was written before the 2004 announcement by the AOU to split the Canada Goose complex.

References:

BATTY, C. and LOWE, T. 2001. Vagrant Canada Geese in Britain and Ireland. Birding World 14:2 pp.57-61.

BURGERS, J., SMIT, J. and van der VOET, H. 1991. Origins and systematics of two types of Bean Geese Anser fabilis wintering in the Netherlands. Ardea 79: 307-316.

DELACOUR, J. 1954. The Waterfowl of the World. London.

FOX, A.D., GLAHDER, C., MITCHELL, C.R., STROUD, D.A., BOYD, H. and FRIKKE, J. 1996. North American Canada Geese (Branta canadensis) in west Greenland. Auk 113: 231-233.

MADGE, S. and BURN, H. 1998. Wildfowl - An identification guide. Helm, Kent.

MILLINGTON, R. and GANTLETT, S. 1999. Reply to letter in Birding World 12:2 p83. on Canada Goose forms. Norfolk, UK.

MORGAN, A. 2001. Alaskan Goose to be removed from danger list. The Sunday Telegraph, August 5th 2001. London.

NATIONAL GEOGRAPHIC SOCIETY. 1999. Field Guide to the Birds of North America, 3rd edition. NGS, Washington D.C.

OGILVIE, M. and YOUNG, S. 1998. Wildfowl of the World. New Holland, London, UK.

RICHARDS, B. 1999. Canada Goose forms. Letter in Birding World 12:2 p82. Norfolk, UK.

SHIELDS, G.F. and WILSON, A.C. 1987. Subspecies of the Canada Goose (Branta canadensis) have distinct mitochondrial DNAs. Evolution 41: 662-666.

Christian Melgar. Worthing, West Sussex, UK. 2001.

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DISTINCT FORM	COMMON NAME	BREEDING LOCATION	WINTERING LOCATION	IDENTIFICATION FEATURES

*canadensis*	Canada Goose (nominate)	SE Canada & NE USA.	Atlantic coast USA.	Large size, long necked. Black neck with white chin strap. Body buff with paler underparts. Second largest form.
hutchinsii	Richardson's Canada Goose	Arctic Canada.	Gulf coast of Texas and Mexico.	Small and dumpy with a square-looking head and short bill. Often short-legged. Can appear silvery - colored at distance. Smallest of the pale forms.
interior	Todd's Canada Goose	Area south and east of Hudson Bay, Greenland; NE Manitoba.	South-eastern USA; North-eastern seaboard of USA; Texas.	Large with very long neck and long, shallow bill.
parvipes	Lesser Canada Goose	Arctic Canada west to eastern Alaska.	Southern USA, chiefly interior California, but also east to Gulf coast and south into Mexico.	Small-medium sized. Long bodied, proportionately shorter necked. Neck can be kinked. Medium bill. Round headed.
taverneri	Taverner's Canada Goose	From the Mackenzie River westwards.	Western seaboard of USA from Washington to northern California.	Smaller and darker than Lesser with more compact head and bill. Often shows dark throat line.
leucopareia*	Aleutian Canada Goose	Some Aleutian Islands.	Central California.	Very small with tiny deep-based bill. Slightly paler than other western forms. Usually a fairly prominent neck-ring.
fulva		Mainly resident coastal British Columbia north to south Alaska.	South to northern California.	Large, uniformly dark rufous.
occidentalis*	Dusky Canada Goose	Coastal southern Alaska.	Vancouver and Oregon.	Darker and smaller than fulva, with shorter & deeper bill and usually lacks neck-ring.
moffittii		Great Basin region of NE USA & SW Canada, east of the Rockies.	Western USA.	Much as maxima but with shorter body and shorter bill and legs.
maxima	Giant Canada Goose	Great Plains of N. USA.	Mostly resident in breeding areas.	Largest race with longer neck and bill but similar in color to canadensis, but usually paler.
*minima**	Cackling Canada Goose	Coastal western Alaska.	Interior California south to northern Mexico.	Smallest form with short neck and tiny bill. Darkest form of all - most are dark-breasted, but some pale. Can exhibit in ideal conditions, a smooth waxy-looking lilac-tinged body plumage.