In 1968, the introduction of opossum shrimp into Montana’s lakes triggered a dramatic decline in the kokanee salmon population. The shrimp fiercely competed with young salmon for essential zooplankton, resulting in a disarrayed food chain. Meanwhile, the lake trout population thrived as they turned to the remaining salmon for sustenance. This shift irrevocably changed Flathead Lake’s ecological landscape and impacted its indigenous fish communities.
