An awareness seems to be dawning that salmon smolt mortality is increased by human activities — both in the nearshore environment and in river systems. A recent biological opinion regarding Sacramento salmon suggested that about 8% of the smolts entering the San Juaquin / Sacramento delta make it through to the ocean. This article mentions an early warning that the Chinook smolts that do make it to the ocean have been doing less and less well in Georgia Basin over the last 12 years. That doesn’t bode well for our southern residents who appear focus on returning Fraser Chinook for 80-90% of their summer diet…
|
Coho, chinook in ‘dramatic’ decline
|
But pink salmon survival rising in B.C. |
Coho and chinook are in decline — but curiously, pink salmon survival appears to be increasing, Richard Beamish of the Canadian Department of Fisheries and Oceans told participants in the biennial Puget Sound/Georgia Basin Ecosystem Conference. |
Scientists have long known that only a small percentage of the juvenile salmon that leave freshwater rivers to live in the sea return to spawn at the end of their lives. But the new research shows that percentage has drastically decreased since 1980. In coho, it dropped from 10 percent to 0.5 percent, Beamish said. In chinook, it decreased from 1 percent to 0.1 percent. |
| Beamish’s research shows that over the past 12 years, the survival of coho in Georgia Strait in their first four months dropped dramatically. About 15 percent of the fish disappear in those first four months, Beamish said. |
|
|
