RENO, Nev. In a lakewide study, a team of scientists lead by University of Nevada, Reno limnologist Sudeep Chandra has found a considerable decline in native fish species density at Lake Tahoe since 1951. In their final report, they are recommending establishing and implementing a management plan to protect the nearshore zone habitat, which is critical to native fish.
"The numbers are alarming, and likely caused by multiple stressors in the nearshore zone," Chandra an assistant professor in the University's Department of Natural Resources and Environment said. "The good news is that the composition is there. The bad news is the decline in number, the decline in native species and the proliferation of non-native fish species."
The Lake Tahoe aquatic ecosystem is impacted by the stressors of nutrient loading, algae growth, invasive species, and habitat alterations, Chandra said. In particular, the nearshore area is of critical concern since it is heavily influenced by human disturbances and is the primary interface with the general public, and it's also the area where fish spawn and develop into adulthood.
Chandra's study found that 58 percent of the 26 historically sampled locations surveyed around the lake showed a decline of species or no native species at all.
Several species of nonnative coldwater sport fish, such as Mackinaw, rainbow, brown and brook trout, have been intentionally introduced to Lake Tahoe to provide and support recreational sport fishing. The Kokanee salmon that run up Taylor Creek at the south end of the lake every fall were introduced to Tahoe in the 1940s. Mackinaw trout, brought here from Michigan in 1894, contributed to the extinction of Tahoe's native Lahontan cutthroat trout in 1939.
For the study, the team focused on the nonnative warmwater fish species bluegill and largemouth bass, both illegally introduced into the lake. By the end of the 1990s, nonnative largemouth bass and bl
|Contact: Mike Wolterbeek|
University of Nevada, Reno