In September 2023, invasive quagga mussel larvae were detected in the Columbia River Basin, the last major North American river basin without an established population. The presence of these and other invasive mussel species such as zebra and golden mussels poses a direct threat to sensitive ecosystems, local economies, and cultural resources. Warming waters and other climate factors may facilitate the expansion of suitable habitats for these species. In turn, the impacts of established invasive mussels could worsen the climate challenges already being faced in the Northwest.