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Date Permissions Signed
Date of Award
Master of Science (MS)
Helfield, James M.
Bodensteiner, Leo R., 1957-
Matthews, Robin A., 1952-
The Salish sucker (Catostomus sp.) is a recently described endemic fish species with a patchy distribution and a narrow geographic range in western Washington and southwestern British Columbia. In this study I examined populations within the Nooksack River watershed, attempting to elucidate the environmental factors contributing to observed patterns of distribution and abundance. I hypothesized that hypoxic and hyperthermic conditions during the summer months would restrict Salish sucker distribution. I tested this hypothesis by measuring dissolved oxygen concentrations, temperature, and Salish sucker abundance and movement at eight sites in the Bertrand Creek and Fishtrap Creek sub-basins. The results of this study did not support my original hypothesis; instead it seems more likely that physical habitat characteristics rather than water quality exert greater influence in patterns of abundance and distribution. My findings emphasize the importance of maintaining the quality and connectivity of habitat for Salish sucker conservation.
Western Washington University
Subject – LCSH
Catostomus--Washington (State)--Nooksack River Watershed; Catostomus--Effect of temperature on--Bertrand Creek Watershed (B.C. and Wash.); Catostomus--Effect of temperature on--Fishtrap Creek Watershed (B.C. and Wash.); Hypoxia--Environmental aspects--Bertrand Creek Watershed (B.C. and Wash.); Hypoxia--Environmental aspects--Fishtrap Creek Watershed (B.C. and Wash.)
Nooksack River Watershed (Wash.); Bertrand Creek Watershed (B.C. and Wash.); Fishtrap Creek Watershed (B.C. and Wash.)
Copying of this document in whole or in part is allowable only for scholarly purposes. It is understood, however, that any copying or publication of this thesis for commercial purposes, or for financial gain, shall not be allowed without the author's written permission.
Lundgren, Nathaniel S. (Nathaniel Stuart), "Factors affecting the distribution and abundance of the Salish sucker (Catostomus sp.): an endemic and endangered transboundary fish population" (2013). WWU Graduate School Collection. 262.