Millions of salmon migrate from the ocean up Canada's Fraser river every year to spawn. In some recent years, salmon that have entered the lower part of the river have disappeared before ever reaching their spawning grounds. Why are the fish vanishing?
- Where is the Fraser River, and why is it an important habit for biologists to study?
- What is the evidence that salmon are disappearing?
- What might have contributed to the recent disappearances of migrating salmon?
Let's investigate these questions
in the lesson that follows >>