Performance of rock deflectors for rearing habitat improvement on a tributary of the Mattole River, Northern California

Graduation Date

1983

Document Type

Thesis

Program

Other

Program

Thesis (M.S.)--Humboldt State University, Fisheries, 1983

Committee Chair Name

Terry Roelofs

Committee Chair Affiliation

HSU Faculty or Staff

Keywords

Humboldt County, Humboldt State University -- Theses -- Fisheries, California, Fish habitat improvement

Abstract

Stream channel physical characteristics and fish populations were documented during the summer low flow period before and after 1981 placement of rock triangular wing deflectors in an effort to improve rearing habitat. Alteration took place in ten 22.9 m sections with ten sections of the same length serving as control sections. As installed in a second order coastal stream (northern California), less than 15% of the structures were functionally intact after a common peak winter flow (5-7 year recurrence interval). Change in juvenile steelhead 0+ and 1+) numbers, density, biomass, and standing crop was not significantly (P 0.05) different for treatment versus control sections. Parr did not necessarily respond to an apparent increase in depth in treatment sections. Mean condition factor for parr was significantly (P0.001) poorer in treatment sections following alteration. Associat-ed observations showed biological parameters more variable for 1+ populations than 0+ populations in 22.9 m sections of Nooning Creek. Temporal change in 1+ populations in control sections was as great as that reported by others and may have been due to extreme high water temperatures record-ed in 1981 or limited suitable space. Populations of 0+ fish did not appear to be affected.

https://scholarworks.calstate.edu/concern/theses/dj52w6906

Share

 
COinS