Date of Graduation
Davis College of Agriculture, Natural Resources and Design
Wildlife and Fisheries Resources
Kyle J. Hartman.
The influence and relative importance of fine sediment on wild brook trout (Salvelinus fontinalis) population size was assessed. Brook trout production in headwater streams was inversely proportional to substrate permeability in one of two years, suggesting substrate composition influenced production. Results suggest the critical fine sediment size for brook trout in this study, is between 0.063 mm and 1.0 mm. Further, fine sediment (<0.063 mm) should not exceed 0.6--1.0% of spawning substrate, or negative population effects may be incurred. Under normal flow conditions, fine sediment was a principal determinant of juvenile trout abundance relative to other physical and biological factors. Adult trout abundance was principally a function of stream discharge, and is potentially further influenced by fine sediment impacts on juvenile recruitment. Spatially restricted food resources, created by drought-induced low flows in year 2 of the study, are believed to have over-powered mechanisms influencing trout abundance under normal flows.
Hakala, James Philip, "Factors influencing brook trout (Salvelinus fontinalis ) abundance in forested headwater streams with emphasis on fine sediment" (2000). Graduate Theses, Dissertations, and Problem Reports. 1125.