Further study found that non-native fish indeed have a lower tolerance to ultraviolet radiation, enabling them to survive in the nearshore areas where clarity is degraded in comparison to the majority of the lake where UV transparency is high, making it undesirable for nonnative fish.
"We proposed that this differential UV sensitivity could be used to develop a "UV Threshold" that could be attained to minimize susceptibility to aquatic invaders," Chandra said. "This value can be easily measured and monitored with a profiling UV radiometer or modeled from water samples analyzed for transparency in the lab with a spectrophotometer, and used to manage nearshore waters."
"We hope that our recommendations will assist in preserving nearshore native fish populations, increasing the cost effectiveness of eradication efforts of invasive warmwater species, and inform mitigation efforts to increase water clarity at compromised sites around Lake Tahoe," Chandra reported in his presentation to Nevada Division of State Lands and the PSW. "Given the potentially high cost of a full scale warmwater fish invasion any expense to implement these largely preventative measures is money well spent."
Chandra and his team completed the "Nearshore Indicators for Clarity, Habitat and Ecological Sustainability; Development of Nearshore Fish Indicators for Lake Tahoe" study for the Pacific Southwest Research Station of the USDA Forest Service and the Nevada State Lands Division, both of whi
|Contact: Mike Wolterbeek|
University of Nevada, Reno