Association of Fall-run Chinook Salmon Redds with Woody Debris in the Lower Mokelumne River, California
نویسنده
چکیده
Surveys in the lower Mokelumne River during 1994-1995 indicated that fall-run chinook salmon, Oncorhynchus tshawytscha, redds associated with woody debris (WD) had smaller substrate and greater mean depths. Also, the proportion of redds associated with WD was negatively related to stream gradient. Female chinook salmon selected spawning sites containing WD in some instances. Woody debris may make less desirable habitats more suitable for spawning and may allow greater concentrations of redds on suitable sites.
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