Globe and Mail: When bears, wolves and other animals drag salmon carcasses from spawning streams they cause an intricate chain reaction that changes the nature of the surrounding forest, according to new research from Simon Fraser University. Plant species that efficiently take up nitrogen from the decomposing bodies of salmon flourish -- and soon there are more song birds, drawn by the dense growths of wild berry bushes and prolific insect hatches.
The change is so dramatic, according to the research done in one of the largest field studies on salmon in the world, that it is possible to look at the forest in a watershed and tell how well the associated salmon run is doing... In addition to looking at plant species, Prof [John] Reynolds said it is important to consider the physical characteristics of a stream as well, because animals avoid fishing in places where getting out of the water with a salmon is difficult because of steep banks.'...
Starting in 2007, a team of 10 researchers began examining 50 relatively small watersheds in the Great Bear Rainforest, a vast area of old growth forest on British Columbia's wild Central Coast. Prof. Reynolds said the area was chosen because there has been little human impact on the watersheds. 'That area is mostly without roads... it is the last place that hasn't been logged,' he said...
The research findings support another recent paper, by Prof. Reynolds and Rachel Field, which found that song bird density and diversity is linked to the size of salmon runs. That paper looked at estuaries and concluded that 'breeding birds may benefit from residual salmon-derived nutrients in landscapes adjacent to spawning grounds and that this trend extends... well beyond the salmon spawning season.'
