The declining salmon and whale numbers raise a critical question: Is the southern resident killer whale population solely reliant on the abundance of salmon? And, if so, since when?
A study of viral variants finds Piscine orthoreovirus continuously spills over from farmed salmon to wild salmon.
As climate change warms northern rivers and changes precipitation patterns, some types of cold-loving fish are failing.
Regulations have lowered mercury emissions globally, but the risks to ocean ecosystems and human health may be getting worse.
Noisy waters may be making it harder for southern resident killer whales to communicate with each other and find their food.