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Stream Temperature Information in KRIS Noyo

KRIS Web Background Pages: Temperature

There is a wealth of temperature data available for the Noyo River, thanks to the advent of inexpensive automated temperature sensing probes. These devices make it possible to collect hourly data for months with a limited number of site visits. The large amount of temperature information regionally has become a powerful tool for analyzing salmonid stream conditions. Protocols for data collection have been provided by the Forest Science Project ( Lewis, 1999).

The Mendocino Redwood Company (MRC) and Jackson Demonstration State Forest (JDSF) both have collected water temperature data since the mid-1990s. MRC staff provided temperature data directly to the Institute for Fisheries Resources (IFR) staff for use in KRIS, while JDSF data were made available through the Forest Science Project (FSP). Most temperature data sets in KRIS have been previously trimmed, to remove outliers, such as temperatures recorded before and after the device is placed in the water.

Hourly data were assimilated into large tables with location columns using the KRIS Hobo Import program . The KRIS Build Table functions were then used to make tables of floating weekly average temperature for all locations. This allows comparisons across locations and at a single location over several years. Also large tables were filtered for one location so that minimum, maximum and average temperatures tables for a given location and year could be constructed.

There are three basic types of temperature charts in KRIS Noyo: 1) floating weekly average temperature, 2) floating weekly maximum temperature, 3) minimum, average and maximum and 4) hourly coho stress. Reference temperatures in these charts vary. The floating weekly average charts use a conservative reference of 16.8 degrees C as the stress threshold for coho salmon. Welsh et al. (in press) and Hines and Ambrose (1998) found that, when floating weekly average temperatures exceeded 16.8 degrees C, coho salmon were absent. Both studies also found that when the the floating weekly maximum temperature exceeded 18.3 degrees C coho were absent. Valentine (1994, 1996, unpublished) studied water temperatures within the Jackson Demonstration State Forest, including the South Fork Noyo River, and provided some analysis and recommendations for management.

This KRIS Noyo chart shows the floating weekly average water temperature in the lower North Fork Noyo River in 1992-1996 and 1999. The maximum floating weekly average temperature in each year exceeds 16.8 degrees C. In these two graphs, MWAT refers to the maximum floating weekly average temperature for the year, as defined by Welsh et al. (in press). Bear Gulch, a South Fork Noyo tributary in Jackson Demonstration State Forest, had floating weekly average water temperatures below 16.8 degrees C in the years 1996-1998. This watershed is close to the coast which provides the cooling influence of summer fog. It is also a small stream and is therefore partially influenced by ground water temperatures.

Minimum, average and maximum daily water temperature comparisons are also presented in KRIS Noyo for various locations and years. These charts show the optimal growth boundaries (10-15 degrees C) for salmonids as determined by Brett (1952).


The chart above shows the minimum, average and maximum daily water temperatures of the South Fork Noyo River above Kass Creek in 1996. The average and maximum water temperatures in July and August routinely exceeded optimal growth limits for salmonids.	The minimum, average and maximum water temperatures of Bear Gulch, tributary of the South Fork Noyo River in Jackson Demonstration State Forest, had temperatures which fell within optimal ranges for salmonid growth throughout summer and fall of 1996.

Optimal growth for salmonids occurs between 10 to 15 degrees C (Brett, 1952). Salmonid disease resistance also falls when water temperatures exceed 16 degrees C (McCullough, 1999). A threshold of 16 degrees C was chosen as a reference for coho stress in KRIS Noyo for the purpose of generating cumulative stress charts.


This graph shows the number of hours in the week that Hayworth Creek at the North Fork Noyo River exceeded coho salmon stress thresholds (16 degrees C) during summer 1996. From late June to mid-August, more than half the hours in each week exceeded 16 degrees C.	Temperatures stressful to coho salmon (>16 degrees C) were exceeded less frequently in Hayworth Creek at the North Fork Noyo River in 1999 than in 1996. Water temperature may vary between suitable and unsuitable for coho salmon at some locations in different years depending on climatic factors.

References

Brett, J.R. 1952. Temperature tolerance in young Pacific salmon, genus Oncorhynchus. J. Fish. Res. Board of Canada. 9(6):265-323. http://www.humboldt.edu/~fsp/tim/1952article.html

Hines, D.H. and J.M. Ambrose. 1998. Evaluation of Stream Temperature Thresholds Based on Coho Salmon (Oncorhynchus kisutch) Presence and Absence in Managed Forest Lands in Coastal Mendocino County, California. Georgia Pacific Corporation, Ft. Bragg, CA. 14 p plus Appendices.

Hines, D. and J. Ambrose. In review. Evaluation of stream temperatures based on observations of juvenile coho salmon in northern California streams. Draft submitted to North American Journal of Fisheries Management. 21 p.

Lewis, T. 1999 . Regional Stream Temperature Monitoring Protocol. Forest Science Project, Humboldt State University. Arcata, CA. 29 pp.

McCullough, D. 1999 . A Review and Synthesis of Effects of Alterations to the Water Temperature Regime on Freshwater Life Stages of Salmonids, with Special Reference to Chinook Salmon. Columbia Intertribal Fisheries Commission, Portland, OR. Prepared for the U.S. Environmental Protection Agency Region 10. Published as EPA 910-R-99-010.

Valentine, B.E. 1994. Noyo River Temperature Study, 1993. CA Department of Forestry and Fire Protection, Coast-Cascade Region. Santa Rosa, CA. 5 pp.

Valentine, B.E. 1996. Stream temperatures on Jackson Demonstration State Forest, Mendocino County, California, during summer of 1995. CA Department of Forestry and Fire Protection, Coast-Cascade Region. Santa Rosa, CA. 19 pp. without figures.

Valentine, B.E. Unpublished. Memorandum dated Nov 30, 1998 to Mark Jameson regarding 1997 water temperature studies on Jackson Demonstration State Forest. CA Department of Forestry and Fire Protection, Coast-Cascade Region. 5 pp.

Welsh, Hartwell, PhD. Personal Communication, USDA Forest Service, Redwood Science Lab, Arcata, CA.

Welsh, H.H., G.R. Hodgson, M.F. Roche, B.C. Harvey. 2001. Distribution of juvenile coho salmon (Oncorhynchus kisutch) in relation to water temperature in tributaries of the Mattole River, California. North American Journal of Fisheries Management. U.S.D.A. Forest Service, Redwood Sciences Laboratory, Arcata, CA. 7 pp.


This KRIS Noyo chart shows the floating weekly average water temperature in the lower North Fork Noyo River in 1992-1996 and 1999. The maximum floating weekly average temperature in each year exceeds 16.8 degrees C. In these two graphs, MWAT refers to the maximum floating weekly average temperature for the year, as defined by Welsh et al. (in press).	Bear Gulch, a South Fork Noyo tributary in Jackson Demonstration State Forest, had floating weekly average water temperatures below 16.8 degrees C in the years 1996-1998. This watershed is close to the coast which provides the cooling influence of summer fog. It is also a small stream and is therefore partially influenced by ground water temperatures.