Like salmon, eulachon are anadromous; they spawn and are born in freshwater but live most of their life in the ocean. Most eulachon will die shortly after spawning. Streams fed by glacial melt are most attractive to this Pacific smelt fish due to the high water levels in the spring.
The eulachon are an important food source for many predators including humpback whales, seals, sea lions, gulls, and bald eagles. This oily fish is also a traditional source of strength for the Tlingit people during harsh winters. The vitamin-rich oil is used to preserve perishable food like berries and for dipping dehydrated foods.