Monitoring
Pat Higgins placing temperature sensor in Tenmile Creek.
Water temperature is the most important water quality variable in terms of understanding stream reach suitability for salmonids. ERRP has been conducting a Tenmile Creek basinwide temperature study since 2018 as part of a California State Coastal Conservancy Proposition 1 grant.
Coho salmon juveniles spend need to spend a year in freshwater, while steelhead may spend up to three years before going to the ocean and both need coldwater for survival. Due to severe drought, extensive reaches of Tenmile Creek and its tributaries lost surface flow in 2020 and 2021 (See Monitoring Report). To learn more about water temperature and salmonids, see: www.krisweb.com/stream/temperature.htm
Chinook salmon carcass on Cahto Creek at Hogan property. 11/14/21. Photo by Philip Buehler.
Steelhead trout juveniles in Mill Creek downstream of restoration site.
Juvenile Chinook at left in lower Streeter Creek. 5/26/22.
Coho salmon juvenile in lower Tenmile at the mouth of Peterson Creek. 6/23/22.
In conjunction with restoration of the gallery forest at the Hogan property, ERRP is initiating an air temperature study of Cahto Creek comparing sites with optimal canopy to those of disturbed sites with little shade. The objective is to involve the community in a long term study tracking progression at the restored site at different stages of ecological succession. Students from Laytonville Elementary School will be invited to participate in the riparian temperature study (see Education). Relative humidity over the stream also influences water temperature, and mature riparian trees maintain cooler more moist air. Learn more at www.krisweb.com/stream/riparian.html
Riparian forests influence air temperature over the stream and water temperature.
Steve Brown taking measurements for V-Star survey of Streeter Creek.
Effects of excess sediment in streams may be subtle, where fines fill spaces between gravel on the bed, or they may be dramatic where pools are filled. A method know as V-Star can be used to measuring fine sediment in pools in order to quantify sediment levels. Excess sediment transport reduces aquatic insect production, decreases salmon and steelhead egg and alevin survival, fills pools and can widen the stream course making it more subject to warming. In the most extreme cases, streams can be so deeply buried that they may lose surface flow. Learn more at: www.krisweb.com/stream/sediment.htmi