When Jo-Anne Chadwick books nature tours on the Harrison River in the late fall, she knows what things bird watchers can expect to see. And until now, people harassing eagles hasn't been one of them.
From mid-November until January, the greatest eagle show on Earth takes place along the waterfront, about 100 kilometres east of Vancouver, where as many as 10,000 bald eagles congregate. The birds cluster in riverbank trees like giant Christmas decorations and gather in massive flocks along the gravel bar flats, where they squabble over dead or dying salmon.
But on Saturday Ms. Chadwick, whose Fraser River Safari eco-tours have been putting people in close contact with eagles for the past six years, saw something that stunned her customers – and left her worrying about the future of the eagles in the area.
"It started out as amazing as always," Ms. Chadwick said of a weekend boat tour. "There were eagles everywhere, and we were idling in the main channel, just drifting along with people taking photos … then the Jet Skis, the kayakers and small jet boats started charging right across the shallows."
She said the small boats "look like predators to the birds," which scatter.
"Then the two helicopters came in … one kept hovering above the flats. It was unbelievable to watch. People were in shock," she said.
"Even the kayakers were scaring the birds. They think they are eco-friendly, paddling along, but when you go into the shallows you see the birds fly up, wheel around and land again, only to have another kayaker come through. After a few times the birds just leave the area," Ms. Chadwick said. "I was watching all this and thinking, 'Holy cow, we've got a problem here.' "
The popularity of the Fraser Valley Bald Eagle Festival, which takes place next weekend, has grown dramatically in recent years because of an enormous increase in the number of birds flocking to the area. But the tourists have been flocking in too, arriving earlier in the season, before the festival starts, and coming in greater numbers.
The increase in birds has occurred because salmon runs have been declining in other coastal rivers, while stocks in the Harrison and its tributary, the Chehalis, have remained strong.
The Squamish River, 70 kilometres north of Vancouver, used to be known as the bald eagle capital of Canada, having racked up a record count of nearly 4,000 birds in 1994. But the Squamish salmon runs have been declining, and only 655 eagles were counted there last year, while the Harrison had more than 10,000 birds, setting a new world record.
Ms. Chadwick said word has been spreading quickly about the remarkable number of eagles on the Harrison, and now the site has become so popular the birds are at risk of getting scared away from their prime winter feeding area.
David Hancock, author of several eagle books and a great promoter of the Fraser Valley Bald Eagle Festival, said in a recent blog that wildlife cameras he has set up on the Chehalis River flats show the extent of the problem.
"It is obvious that the eagles are suffering greatly from recreational human activities," Mr. Hancock wrote. "Over the past three days of watching our cams … it is apparent that shortly after sunrise through dusk, the Flats are subject to a constant stream of kayakers, canoeists, hikers, jet boaters and even helicopters and Sea-Doos."
Mr. Hancock said boats that stay in the main river channel, and people who remain on the riverbank walks, aren't disturbing the birds, but something has to be done to keep people off the flats.
"What is needed is a respectful treatment of the central Chehalis Flats where the eagles need peace and quiet," Mr. Hancock stated. "We need to come up with an immediate policy on not trespassing on these central flats."