| Walker Lake, NV has experienced extreme declines in lake levels since 1882. These changes have caused increased salinity in the water and ultimately the extirpation of three fish species, leaving only tui chub (Gila bicolor) and Lahontan cutthroat trout (Oncorhynchus clarki henshawi) in the lake. Insufficient field studies addressing the physiological impact of changing abiotic conditions on fish in the lake motivated this study. Biweekly surveys were conducted from 12 May 2003--23 April 2005; fish were enumerated and data on water temperature, conductivity and dissolved oxygen were collected. Fish were found throughout the lake, including areas deemed suboptimal for Lahontan cutthroat trout, regardless of abiotic conditions. It is not yet possible to determine habitat preferences in the lake. Without increases in water inflow, Walker Lake will clearly become devoid of fish within a few years, affecting the ecosystem's food chain. |
