Fish and mammals of the lower Calaveras River, Stockton, CA

• Main Author: Blocker, Sara D.
• Format: Text
• Language: unknown
• Published: Scholarly Commons 2009
• Subjects: Mammals Calaveras River (Calif) Identification; Freshwater fishes Calaveras River (Calif) Identification; Fishes Calaveras River (Calif) Identification; Biology; Life Sciences; American River; Rattus rattus; Lontra
• Online Access: https://scholarlycommons.pacific.edu/uop_etds/719; https://scholarlycommons.pacific.edu/context/uop_etds/article/1718/viewcontent/blocker_sara_04022018153652.pdf

The San Joaquin-Sacramento River Delta (SJSRD) of California is a riparian habitat that sadly represents the destructive forces and consequences of human impacts. A tributary to the SJSRD, the Calaveras River in Stockton, California, is a par1icularly degraded riparian system that recently has not been the focus of restoration effor1s. This study provides data about the current fish and mammals found in the Lower Calaveras River prior to any restoration efforts. Fish were sampled from February 2008 to February 2009 using a seine net and gill net. Fish were identified to species and length measurements and abundance were recorded. A total of 15 species were documented, only one of which was native (Sacramento sucker, Catostomus occidentalis). Dominant species throughout the sampling period included mostly those in the Family Centrarchidae. Other fish observed were golden shiners (Notemigonus crysoleucas), threadfin shad (Dorosoma petenense), and western mosquitofish (Gambusia aj]inis). Fish assemblage varied with changes in season and percent coverage of submerged aquatic vegetation (SA V). Bluegill and redear sunfish abundances were positively correlated. Largemouth bass and redear sunfish abundances were positively related to the percentage of SA V and to changes in season. Presence of mammals was documented using several techniques including livetrapping, soot track plates, photography, and remote sensor infrared trail cameras. Native mammals included North American river otter (Lontra canadensis), striped skunk (Mephitis mephitis), raccoon (Procyon lotor), Botta's pocket gopher (Thomomys bottae), Califomia vole (Microtus californicus), California ground squirrel (Spermophilus beecheyi), desert cottontail rabbit (Sylvilagus auduboni), and beaver (Castor canadensis). Introduced species included house mouse (Mus musculus), black rat (Rattus rattus), muskrat (Ondatra zibethicus), and European rabbit (Oryctolagus cuniculus). House mice were only captured in traps October 2008 through March 2009, and more males ...