1968 Montana shrimp stocking led to salmon collapse and lost food for eagles and bears

An ecosystem collapse in Montana remains a lasting lesson in how well-intentioned wildlife management can have devastating consequences. When state wildlife officials introduced a non-native, tiny crustacean into nearby lakes in 1968, the goal seemed simple. They believed stocking the opossum shrimp, Mysis diluviana, would provide an extra food source and help increase populations of kokanee salmon. Instead, the move set off a chain reaction across Flathead Lake, causing the salmon population to collapse and removing a major autumn food source for hundreds of migrating bald eagles and grizzly bears. The full scale of the ecological change was described in research by Craig N. Spencer, B. Richard McClelland, and Jack A. Stanford, published in the journal BioScience under the title Shrimp stocking, salmon collapse and eagle displacement: Cascading interactions in the food web of a large aquatic ecosystem.