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San Luis Rey River Water Quality 
Analysis: Steelhead Restoration

Find Out More on San Luis Rey River
Silver Creek

This restoration project on Silver Creek focuses on restoring and protecting two miles of stream for re-establishment of a viable Lahontan Cutthroat (LCT) population. Silver Creek is a tributary to the West Walker River between Bridgeport, California and Lake Tahoe in the Eastern Sierra. This region supports a strain of cutthroat trout native to that area- the Lahontan cutthroat trout (LCT). Due to pressures on native populations, the LCT occupies only 8.6% of their historical stream habitat, and Silver Creek supports one of six viable stream populations in the Walker River Basin. Silver Creek was closed to recreational fishing in 1995 to support LCT recovery. But, subsequent illegal stocking of non-native brook trout has impeded federal and state agency efforts to restore the LCT to their native range and re-open Silver Creek to recreational fishing. This project will eradicate non-native brook trout from this stretch of Silver Creek and install a temporary barrier to block migration of brook trout into the two-mile stretch being prepared for LCT re-introduction. As always, it takes a village….and this is no exception. This project is a collaborative partnership among Trout Unlimited, California Department of Fish and Wildlife, Sierra Pacific Flyfishers, Deep Creek Flyfishers, Golden State Flycasters, Southwest Council International Federation of Fly Fishers, CalTrout and other conservation groups and local community volunteers.

Escondido Creek Project Summary

(2007) California Wildlands Grassroots Fund/Tides Foundation grant awarded to Golden State Flycasters for water quality analysis in Escondido Creek.

The Escondido Creek Project was designed to assess water quality over a one year period in Escondido Creek as a candidate steelhead recovery stream in San Diego County and to establish a highly trained group of GSF/TU-San Diego volunteers for water quality analysis and habitat restoration in support of steelhead recovery efforts in Southern California. Our stream sampling studies generated two complementary types of water quality data for Escondido Creek: a “snapshot” view of current water quality through on-site water chemistry tests, and a long-term view of water quality through bioassessment which uses macroinvertebrate population indicators based on their differential tolerance limits to water impurities. We worked collaboratively with San Diego Coastkeeper on sampling training and logistics, and received training from California Department of Fish and Game in the latest Surface Water Ambient Monitoring Program (SWAMP) Bioassessment protocol. Macroinvertebrate samples obtained from bioassessment sampling at five sites over a two year period by GSF/TU volunteers were analyzed by Weston Labs in San Diego. Overall, the water chemistry studies showed good water quality characteristics of water temperature and high dissolved oxygen levels, and had relatively high conductivity and nitrate levels at the five sites tested between the coast and Escondido Creek Preserve. The Index of Biotic Integrity (IBI) is a standardized ranking of water quality based on macroinvetrebrate population distribution, and had lower scores than headwater reference sites in San Diego County. Escondido Creek remains one of the most logistically simple steelhead trout re-introduction passageways in San Diego County due to adequate water flow, lack of urbanization, a managed lagoon, extensive canopy cover, and lack of near-ocean migration barriers.

Final Report from Golden State Flycasters submitted to Tides Foundation for Grant TFA07-00015: Bioassessment Analysis of Water Quality in Escondido Creek, San Diego County.
Southern California Trout Genetic Study

(2010) California Department of Fish and Wildlife grant awarded to Trout Unlimited Chapter 920 (San Diego) for genetic analysis of rainbow trout populations in Southern California rivers and streams extending from Ventura County to San Diego County.

The primary objective of this study was to document the location and genetic lineage of existing rainbow trout populations in the southernmost extent of their native range to support ongoing and future steelhead recovery efforts. It was the first large-scale population genetic analysis of O. mykiss in this southern region that used statistical analysis of data from high resolution microsatellite and SNP genotypes. Over 600 caudal fin clips were collected from trout residing in twenty seven creeks and rivers spanning ten watersheds extending south from Montecito Creek, through the Santa Clara River watershed, to the Sweetwater River watershed in San Diego County. Prior to this study there was little data on trout in this geographic area. About 75 exploratory and tissue collection trips between 2010 and 2013 were performed throughout the southern watersheds by volunteers from the Trout Unlimited -San Diego Chapter and colleagues, and CDFW fisheries biologists. The tissue samples were submitted to the NOAA Fisheries Service Southwest Fisheries Science Center in Santa Cruz, where samples were processed and analyzed by staff of the Molecular Ecology and Genetic Analysis Team. Genotypes from individual trout sampled from focal populations were combined with those from previously genotyped O. mykiss populations throughout California, including seven hatchery rainbow trout strains and O. m. nelsoni, a subspecies of trout from Baja California, Mexico, for a total of 2,180 fish analyzed. This analysis identified two major classes of existing trout in this region, native coastal steelhead lineage and hatchery rainbow trout. The majority of the populations sampled were of hatchery descent. Only three groups of populations in the southernmost rivers contained significant evidence of native coastal steelhead ancestry: the San Luis Rey River in San Diego County, Coldwater Canyon Creek in the Santa Ana River watershed in Riverside County, and populations from the San Gabriel River in Los Angeles County, with the exception of the Iron Fork and Devil’s Canyon Creek populations. This study provided evidence that habitat conditions are sufficient in southern watersheds of the Southern California Steelhead Distinct Population Segment to support survival of trout that are of native coastal steelhead lineage. Although these trout historically migrated between the ocean and fresh water, they have been locked into their headwaters for many generations due to dam building, habitat degradation and low water flow. This study has now demonstrated where these native populations are and will help focus efforts by fisheries managers, policy makers and restoration workers to protect these populations and increase their numbers.

Final Report from Trout Unlimited – San Diego Chapter (Jacobson, Marshall, Dalrymple, Kawasaki, Pearse, Abadia-Cardoso and Garza; 3-31-2014) submitted to California Department of Fish and Wildlife / Fisheries Restoration Grant Program for Grant P0950015: Genetic Analysis of Trout (Oncorhynchus mykiss) in Southern California Coastal Rivers and Streams.