In July, Ducks Unlimited Regional Biologist Kelly Warren joined biologists from the Alaska Department of Game and Fish and US Forest Service (USFS) to collar and band more than 600 Dusky Canada geese near Cordova, Alaska, on the Copper River Delta.
“These geese nest primarily on the Copper River Delta in Alaska,” Warren said. “They are the only geese that winter almost exclusively in the Willamette Valley, lower Columbia River and the coast of Oregon and southwest Washington.”
In 1964, an 8.5 magnitude earthquake altered the landscape of the Dusky geese’s core breeding grounds by lifting the Copper River Delta by as much as 6 feet, altering preferred nesting habitat and making nests more accessible to predators such as brown bears, wolves, and coyotes.
Middleton Island is where Duskys were transplanted after the 1964 earthquake to encourage an expanded breeding range outside of the Copper River Delta.
“Middleton Island has approximately 1,500 breeding Dusky geese,” Warren said. “The island has likely reached carrying capacity, but it remains an important breeding area for Duskys. The Alaska Department of Fish and Game (ADFG) does bi-annual nest plot surveys to evaluate production.”
Duskys also deal with an increase in other goose subspecies in the region, land use and development.
“The collars provide critical information including distribution, behavior, migration, longevity and more,” Warren said.
The Dusky is one of seven Canada goose subspecies that winters or migrates through the northwest United States. Dusky Canada geese have a very low population, around 12,000 birds, which requires special goose management and hunting requirements in the Willamette Valley, Lower Columbia River and southwest Washington.
While other dark geese subspecies can be harvested in these areas, it is illegal to hunt Duskys, which can be distinguished from other Canada goose subspecies by their medium size and a dark chocolate brown chest that has little contrast with their black neck.
Due to the heightened possibility of misidentifying and illegally harvesting a Dusky, goose hunting in these special management areas require hunters to take a goose identification test to acquire a permit. For more information listen to DU Podcast Episodes 62 and 63.
The red and green Dusky neck collars help identify a Dusky.
“Cooperative efforts between the USFS - Chugach National Forest and Ducks Unlimited have been ongoing since 1997 to find ways to assist Duskys with the issues they face on the breeding grounds,” Warren said. “This includes the initiation and management of an artificial nesting island program. There are more than 500 artificial floating fiberglass nest islands in the Copper River Delta that provide secure nest sites away from brushy corridors and perch trees heavily used by aerial predators. The use of these structures has gradually increased and nest success has been higher for birds using the structures than those using traditional nesting cover. It is critical that the dusky harvest stay closed or at restrictive low levels. If the population falls below a certain threshold, decreased hunting opportunities for all dark geese subspecies could follow.”
You can be a part of the conservation and management of Dusky Canada geese by photographing collared Dusky geese and reporting them to Tasha DiMarzio of ADFG at tasha.dimarzio@alaska.gov.
Ducks Unlimited Inc. is the world's largest nonprofit organization dedicated to conserving North America's continually disappearing waterfowl habitats. Established in 1937, Ducks Unlimited has conserved more than 15 million acres thanks to contributions from more than a million supporters across the continent. Guided by science and dedicated to program efficiency, DU works toward the vision of wetlands sufficient to fill the skies with waterfowl today, tomorrow and forever. For more information on our work, visit www.ducks.org.