The bald eagles typically found this time of the year along the upper Skagit River are instead being seen in western Skagit County and along the Nooksack River in Whatcom County.
They have been spotted in large numbers in the Samish Flats and on Fir Island, areas they don’t typically frequent until February and March.
“In the Samish Flats, we’ve had an amazing number of eagles ... I think there’s more eagles than ever,” state Department of Fish & Wildlife Biologist Paul DeBruyn said. “I counted 50 eagles in one tree.”
Many wildlife experts theorize the birds moved west to find food, which has been in low supply on the Skagit River this season.
Following the fish
Erica Keene, Skagit Eagle Watchers program coordinator for the Mt. Baker-Snoqualmie National Forest, estimates there are 40 percent fewer eagles on the upper Skagit River this winter than last winter.
Her best guess as to why is the low chum salmon returns on the river.
“There is a high correlation between salmon numbers and eagle counts,” Keene said.
State Department of Fish & Wildlife Fisheries Biologist Brett Barkdull said while the state agency is still tallying a final count for the Skagit River’s hatchery chum salmon run, it will be lower than the 14,000 expected.
Low returns may not be the only reason there are fewer eagles on the upper Skagit River.
Fisheries managers have said returning salmon are smaller than normal this year — likely the result of a mass of warm water in the Pacific Ocean called the blob — and fall floods may have flushed salmon carcasses downstream, removing the biggest draw for the visiting birds.
While some bald eagles live in the state year-round, the bulk of them migrate from Alaska and Canada to winter along the state’s best salmon rivers and streams.
And with less food on the Skagit River, those birds likely moved on to other areas.
“Eagles are scavengers, they don’t really hunt much. So if there’s not an easy food source they’re going to go somewhere else,” Keene said.
Fewer feathered friends
For six weeks in December and January, a team led by Keene counted bald eagles along the Skagit River between Sedro-Woolley and Newhalem.
The team spotted 766 eagles this winter, about half the 1,311 birds counted last year.
This year’s count is the second-lowest since 1998. The lowest was two years ago, when 712 bald eagles were spotted, according to Skagit Eagle Watchers records.
“Eagle numbers on the Skagit have seemed lower this year than typical,” North Cascades National Park Service Complex Wildlife Biologist Jason Ransom said in an email. “Presumably this is due to a weaker chum salmon run and then some heavy flood events earlier in eagle season that washed salmon carcasses downstream.”
Also, the Christmas Bird Count results in the North Cascades this winter showed the lowest bald eagle numbers since 2005.
A group of 10 volunteers taking part in the North Cascades count on Dec. 19 spotted 15 bald eagles along Highway 20 between the North Cascades National Park boundary and Diablo Lake.
Since 2005, when 14 eagles were counted, the number has been in the 20s and 30s most years, and reached 41 birds in 2014, according to Christmas Bird Count data.
Ransom leads the North Cascades Christmas Bird Count, which is part of an annual National Audubon Society research effort in its 116th year.
He said other than the low number of eagles, the one-day survey was not unusual.
U.S. Fish & Wildlife Service Pacific Region Eagle Coordinator Matthew Stuber said there are many reasons eagles may congregate in different areas during the winter. The reasons include weather patterns and food supply.
Stuber said the lack of eagles along the upper Skagit River is not indicative of trouble for the species.
“We have evidence that suggests that bald eagle populations are doing very well and growing across most of North America,” he said in an email.
Ransom and Keene also said they don’t think fewer bald eagles on the upper Skagit River indicates a decline in the bird population. They suspect the eagles simply moved elsewhere.
“I assume that eagles are just displaced rather than the population having actually declined. The Nooksack has seen some large numbers this year,” Ransom said.
Barkdull said the Nooksack has had better chum returns in recent years than the Skagit River.
While the Nooksack is a smaller river system than the Skagit, it has met or exceeded the state’s chum return forecasts in recent years, Barkdull said. The Skagit has fallen short of expected returns.
Sightings still possible
Ember LaBounty, who volunteers at the Skagit River Bald Eagle Interpretive Center at Howard Miller Steelhead Park near Rockport, said she has seen the number of eagles drop over the past few years with the low chum returns and November floods.
But during her 20 years at the interpretive center, she said she’s never seen the number of eagles in the area as low as this year.
Still, the center is having plenty of people drop by when it is open on Saturdays and Sundays, and visitors still have a good chance of seeing an eagle or two, LaBounty said.
Cheryl Werda, office manager for the Concrete Chamber of Commerce, said the Skagit River Eagle Festival remains in full swing though January. Details on events, which are held at locations from Concrete to Marblemount, can be found online.
Chamber staff haven’t noticed a drop in the number of visitors, she said.
“Honestly I think our biggest competition with the festival is the Seahawks,” Werda said.