Golden Eagles Fly Over Nabesna
The group of Raptor seekers heading to the viewing hill. There were folks who came from all parts of the Copper River Basin and beyond. Photo by Tenley Nelson
April 21, 2023
Tenley Nelson - Featured Columnist
WISE annually provides science lectures for the public in the late winter in the Copper Basin. On April 8, WISE and the Wrangell Mountains Wilderness Lodge at 28-mile Nabesna Road hosted an in-person group of about 30 people interested in learning more about raptor migration.
National Park Service Wildlife Biologist Carol McIntyre has been studying golden eagles in Denali National Park since 1987. She started counting raptors in the early spring in Wrangell St Elias National Park (WRST) in 2014, spending a month on the Nabesna Road.
A mere decade ago, no one knew this migration existed. Danny Rosenkranz, while doing a snow survey for the NPS one spring about 10 years ago, counted over 50 golden eagles in a day near Dead Dog Hill. After hearing about this large number of birds sighted, Carol annually counted raptors in WRST and documented what is a very large golden eagle migration flyway.
Photo courtesy of Shutterstock
It is a challenge to count birds in the wilderness day after day in the wind and snow. The Wrangell Mountains Wilderness Lodge has provided a home away from home for Carol and her husband during the month they are out counting for the past three years, easing the daily demands of winter camping as well as providing the young and capable assistants, Ike and Nuala Rego.
The Regos provided our group with an excellent lunch of moose stew, pumpkin soup, vegetables, fresh bread, and brownies to fortify us for our outdoor afternoon adventure.
While our group of 30 or so people gathered in the lodge parking lot pulling on gloves and snowshoes, the first eagle of the day cruised over the treetops. We were quickly taught by Nuala how to identify the bird. First, size. It is large, so it is an eagle. Second, it is dark brown and has a small head and a big tail. Golden eagle! If it had a head about the same size as the tail and potentially some white spots under the wings, it would have been an immature bald eagle.
Golden Eagle. Photo courtesy of Shutterstock
The golden eagles, along with other raptor species including but not limited to goshawks, rough-legged hawks, bald eagles, merlin, and osprey, cross the prairies and start flying up the Rocky Mountains. When they get to the Wrangell Mountains, they diverge into two flyways.
Some birds fly a southern route over the Chitina River Valley between the Chugach and the Wrangell mountains and head west and south to nesting grounds. Other birds fly north between the Wrangell and Nutzotin and Mentasta Mountains heading to the interior and west to nest. Individual birds always migrate to the same nesting grounds year after year.
Golden eagles are serial monogamists, staying with the same partner for an entire breeding and rearing season but not keeping the same partner year after year. Older birds fly up earlier and are settled in their territory on nests by early to mid-April. Younger birds not yet breeding straggle through in mid to late April. Eagles do not fatten up for migration like some birds do and must eat along the way. It is speculated that they consume snowshoe hares, grouse, ptarmigan, voles, shrews, and carrion.
The WISE group hiked and snowshoed about a mile away from the lodge and up a small hill. We spent the next several hours scanning the sky with binoculars for birds flying north. Local non-migrating raptors can be identified by their flight behavior, circling around and heading back south, while the migrating birds will generally keep moving steadily north. Four Golden Eagles, two Bald Eagles, and two rough-legged hawks heading up the flyway were spotted while I was with the group.
Hank Colleto Head Ranger WSENP and Carol McIntyre NPS Wildlife Biologist leading the group to the viewing area. Photo by Tenley Nelson
Where are they nesting? What are they eating? What winter grounds did they come from? There are still many questions unanswered! Carol has a goal to place tracking harnesses on 30 birds to learn more about these birds but so far, has only been successful with attaching three due to the extreme challenge of capturing such large creatures.
Wrangell St Elias National Park and Preserve provides important habitat and small game to fuel these large birds on their way north in what may be the largest golden eagle migration in North America. So much has been discovered about this migration in the past ten years, and so much remains to be learned about these large raptors.
Looking for eagles. Photo by Tenley Nelson
