Mount Rainier’s fish-stocking legacy threatens native aquatic species

View of the Ohanapecosh River and predated Northwestern Salamanders (Ambrystoma gracile) eaten by introduced trout. Mount Rainier’s glaciers and snowfields feed a magnificent system of icy streams and mountain lakes. On the surface, these waters look pristine, scattered pools in one of America’s most iconic landscapes. But beneath the surface, scientists are looking at a legacy that stretches back more than a century. According to a report published by USGS Publications, between 1915 and 1972, over nine million fish were stocked in lakes and streams throughout Mount Rainier National Park. The mission was simple to create fishing opportunities for recreation. But stocking these naturally fishless waters with fish did more than give anglers new opportunities. They altered aquatic ecosystems and placed new pressures on native species. Today the park has about 35 lakes and many streams still supporting breeding populations of non-native fish, adds the report. If we go by the report published by the National Park Service, before fish were introduced, all lakes in Mount Rainier were naturally fishless. The absence of fish provided amphibians with relatively secure breeding sites and habi...