Water Temperature, Dissolved Oxygen, Flow, and Shade Measurements in the Three Stream Sections of the Golden Trout Wilderness.

摘要

To determine the current range of water temperatures in the streams inhabited by California golden trout, Oncorhynchus mykiss aguabonita, I deployed and monitored water temperature recording probes from 2008 through 2013 in three meadows in the Golden Trout Wilderness (GTW). Ninety probes were placed in three meadow streams: Mulkey Creek in Mulkey Meadows (elevation 2838 m), South Fork Kern River in Ramshaw Meadows (2640 m), and Golden Trout Creek in Big Whitney Meadow (2963 m). Year-round water temperatures were successfully downloaded from 83 probes along with measurements of dissolved oxygen, flow, and shade. Water temperatures ranged from -0.1 to 26 °C in Mulkey and Ramshaw Meadows, whereas in Big Whitney Meadow, maximum temperatures did not exceed 21 °C. Temperatures were highest in late July through mid-September. Future monitoring can build on the detailed temperature data reported here to further assess climate warming in the streams occupied by this important native trout. Salmonids generally prefer cool water and become stressed when temperatures exceed 22 °C. Thus, these results indicate that current GTW stream temperatures are high and may lack the resiliency to withstand increased water temperatures from climate warming, predicted to increase from 1 to 7 °C within the next 100 years.