Salmon's moveable feast of food and contaminants

[...]salmon-based subsidies are especially relevant for other animals across aquatic and terrestrial food webs because they are in organic forms, such as methyl mercury, that animalscan easily assimilate into theirtissues. Chinook salmon (Oncorhynchus tshawytscha), which feed at the highest level of the food chain for salmon, have the lowest ratio of nutrients to contaminants, whereas pink salmon, which feed at the lowest level, have the highest ratio. [...]the increasing proportion of pink salmon relative to other species over the 40-year period has led to an overall increase in nutrient transport relative to that of contaminants. Many Indigenous communities in the study region have strong cultural and dietary ties to Pacific salmon migrations, and changing risk-benefit ratios could threaten human health as well as ways of life.