Geology Reports⌕ Search
Home/Archive/USGS

USGS · 70199490

Native fishes of the Sacramento-San Joaquin drainage, California: A history of decline

Larry R. Brown·Peter B. Moyle
View original source ↗Export metadata ↓

Abstract

In this paper, we review information regarding the status of the native fishes of the combined Sacramento River and San Joaquin River drainages (hereinafter the "Sacramento-San Joaquin drainage") and the factors associated with their declines. The Sacramento-San Joaquin drainage is the center of fish evolution in California, giving rise to 17 endemic species of a total native fish fauna of 28 species. Rapid changes in land use and water use beginning with the Gold Rush in the 1850s and continuing to the present have resulted in the extinction, extirpation, and reduction in range and abundance of the native fishes. Multiple factors are associated with the declines of native fishes, including habitat alteration and loss, water storage and diversion, flow alteration, water quality, and invasions of alien species. Although native fishes can be quite tolerant of stressful physical conditions, in some rivers of the drainage the physical habitat has been altered to the extent that it is now more suited for alien species. This interaction of environmental changes and invasions of alien species makes it difficult to predict the benefits of restoration efforts to native fishes. Possible effects of climate change on California's aquatic habitats add additional complexity to restoration of native fishes. Unless protection and restoration of native fishes is explicitly considered in future water management decisions, declines are likely to continue.

Explore related subjects

American Fisheries Society SymposiumArticle

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Larry R. Brown, Peter B. Moyle. 2005. Native fishes of the Sacramento-San Joaquin drainage, California: A history of decline. https://pubs.usgs.gov/publication/70199490

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related USGS reports

USGS2019

Changes in body condition and diet of lotic Smallmouth Bass across two flow regimes during summer months at the southern extent of their native range

The Ozark Plateau is located at the southern extent of native Smallmouth Bass Micropterus dolomieu range and water temperature and drought conditions during summer months may potentially affect growth of Smallmouth Bass in this region. Groundwater streams in the region do not warm to the same extent as runoff streams during summer months and could provide a thermal refuge habitat for Smallmouth Bass from high summer temperatures and drought conditions. Our study objective was to examine differences in body condition and diet of Small-mouth Bass through summer months between groundwater and runoff streams. We sampled Smallmouth Bass from eight streams across two the flow regimes monthly from June-September from 2014 to 2016 in the Ozark Plateau of Arkansas and Missouri. Relative weights were calculated and diet contents were examined for each fish. Linear mixed model analyses indicated that relative weights declined in both stream types in 2014 and 2015, but not in 2016. Surprisingly, there was no significant difference in change in relative weights between runoff and groundwater streams in any year. No diet shifts over the course of the summer were noted in any year, and no differences were seen between stream types. Our results suggest that further work should investigate the refuge qualities of groundwater streams for Smallmouth Bass in this region as Smallmouth Bass from both stream types may currently respond similarly to summer conditions.. Middaugh, Chris & Magoulick, Daniel. (2019). Changes in Body Condition and Diet of Lotic Smallmouth Bass across Two Flow Regimes during Summer Months at the Southern Extent of Their Native Range. The Ozark Plateau is located at the southern extent of native Smallmouth Bass Micropterus dolomieu range and water temperature and drought conditions during summer months may potentially affect growth of Smallmouth Bass in this region. Groundwater streams in the region do not warm to the same extent as runoff streams during summer months and could provide a thermal refuge habitat for Smallmouth Bass from high summer temperatures and drought conditions. Our study objective was to examine differences in body condition and diet of Small-mouth Bass through summer months between groundwater and runoff streams. We sampled Smallmouth Bass from eight streams across two the flow regimes monthly from June-September from 2014 to 2016 in the Ozark Plateau of Arkansas and Missouri. Relative weights were calculated and diet contents were examined for each fish. Linear mixed model analyses indicated that relative weights declined in both stream types in 2014 and 2015, but not in 2016. Surprisingly, there was no significant difference in change in relative weights between runoff and groundwater streams in any year. No diet shifts over the course of the summer were noted in any year, and no differences were seen between stream types. Our results suggest that further work should investigate the refuge qualities of groundwater streams for Smallmouth Bass in this region as Smallmouth Bass from both stream types may currently respond similarly to summer conditions.

Arkansas, Missouri↗