The Bald Eagle – Our Great Conservation Success Story.
Saturday, September 15 2012 @ 01:31 AM EDT
Contributed by: davidh
Bald Eagles are iconic. They are big spectacular predators but prefer to be pirates and scavengers. They are very territorial but gather by the thousands to share in and squabble over temporary and annual food surpluses like the spawned out salmon carcasses. The bald eagle is the symbol of wildness but it has invaded our city parks and suburban areas where they can reproduce more successfully than in the wilderness. The Bald Eagle is the American National Symbol – but most bald eagles live in and pass through Canada. But we Canadians like to share so we invite you all to come to the World’s Greatest Bald Eagle Gathering Site – the Fraser River Bald Eagle Festival at Harrison Mills, British Columbia this fall. Thousands of eagles will be here -- Will you?
But why are there so many eagles on the Harrison – Chehalis River complex? The reasons are good and bad. The good part is that the Chehalis Flats, an alluvial fan draining the Chehalis River into the Harrison River, is fortunately still one of the richest salmonid rivers in Canada, hosting all 5 species of salmon, 3 trout and a huge population of 180 million year old sturgeon. On top of this the spawned out carcasses attract thousands of gull, waterfowl and the world’s largest gathering of eagles. The other ‘good’ element is that our southern British Columbia coastal rivers do not freeze up in the winter and this allows late season spawning of the salmon. In the colder more northern rivers of Alaska and BC the salmon spawn early and the dead carcasses become the early season buffet but as soon as the freezing weather comes their dinner is locked under the ice. Southward the eagles come – by the thousand
The not-so-nice part of the story is about human induced changes in the eagles’ migratory patterns. One of the west coast’s greatest food sources for bears, wolves and eagles has been the huge spawning runs of chum salmon. Until recently this was a commercially neglected species and our predators could fatten up for winter. In the last few years we humans have so greatly depleted the other more valuable salmon species that we have now turned to harvesting the formerly “ inferior dog or chum salmon’ . We are now leaving nothing for the predators and scavengers.
The recent sharp decline in chum salmon has meant the eagles have had to cut short their northern migration and more quickly move south, even before the freeze up, because there were no salmon to eat in the northern rivers. The Chehalis – Harrison River complex is the southernmost largest salmon spawning grounds left. We are the eagles’ last and greatest gathering site. Come and join our Fraser Valley Bald Eagle Festival, November 17 and 18, and during the following weekend through Christmas. If the salmon carcasses hold we sometimes get a few thousand eagles still holding into January and early February.
View the details of the FVBEF at: www.fraservalleybaldeaglefestival.ca
Also watch the Hancock Wildlife Foundation / FVBEF sponsored live streaming cams located out on the Chehalis alluvial fan. Some days they can be not just seen feeding on the salmon carcasses but sitting and resting on our cams!
David Hancock, wildlife biologist
Hancock Wildlife Foundation / Fraser Valley Bald Eagle Festival