Big winter awaits B.C’s eagle-eyed birdwatchers
The tiny Fraser Valley community of Harrison Mills is preparing to host thousands of visiting bald eagles in the world’s largest gathering of nature’s foremost dead salmon connoisseurs.
The area’s 600 local nesting pairs could be joined by about 35,000 migratory bald eagles this winter in a perfect coincidence of auspicious weather and feeding conditions, said biologist David Hancock.
As many as 15,000 of those birds regularly visit the Harrison Mills area through the winter viewing season, which kicks off Nov. 17 and 18 with the Fraser Valley Bald Eagle Festival.
The dead spawned-out salmon carcasses that litter the Chehalis Flats are a powerful lure for eagles that make their homes in northern B.C. and Alaska, especially after the streams and lakes they forage from freeze over.
All that food should be ripe for the picking as long as the Fraser Valley is spared heavy rain in the next few weeks.
“If the buffet stays set, they will come,” said Hancock. “They come down here looking for a handout.”
If the rivers rise substantially, the carcasses will be washed into deep water and the eagles will disperse to forage over a larger area or simply move on as far as the Mississippi River.
In 2010, a record sockeye run left tens of millions of dead salmon on river banks throughout the Fraser Valley and attracted a massive gathering of eagles, said Hancock. More than 7,000 were counted in a four-kilometre stretch, which made for spectacular nature viewing.
As the weather in northern B.C. gets colder, up to 500 eagles a day will flow into the Harrison Mills area like they did during a cold snap in October. More than 2,000 are already here.
The public’s relationship with bald eagles has evolved considerably since the 1950s, when predators of all kinds were routinely killed, said Hancock. Back then, fishermen could shoot bald eagles on their run up the coast and collect a bounty in Alaska.
“When you could get $2 for a pair of eagle legs, they would fill buckets with them and it would pay for their gas,” he said.
Since then, bald eagle numbers have rebounded on the West Coast, helped along as expanding human development pushed back the forest and created more open hunting grounds. And that’s not the only way humans have helped.
Over the decades, garbage dumps have become a habitual food source for bald eagles, which also gather there by the thousands.
“We see huge concentrations and especially if we put out a few thousand pounds of food like we do at the landfill,” he said.
As organics are increasingly diverted from the waste stream into composting operations, eagles are being deprived of that food source.
The Hancock Wildlife Foundation has started fitting migratory eagles with GPS trackers in co-operation with the Bald Eagle Tracking Alliance in order to find out where they go in their search for food.
The tiny backpacks are solar powered and ping off cellular towers as the birds fly across the landscape, from Alaska and as far as Louisiana. People can track their movements through the beta page at hancockwildlife.org.
Brackendale, near Squamish, is also a prime eagle-viewing area with volunteer interpreters at Eagle Run dike between 10 a.m. and 3 p.m. on weekends, which started Saturday.