Date of Graduation
Master of Science in Environmental Management (MSEM)
Pacific salmon populations are significantly lower than historic levels on the Western Coast of the United States. The Oregon Coast coho salmon Evolutionary Significant Unit (ESU) was listed as threatened under the Endangered Species Act in February 2008. The total number of adult coho salmon returning to Oregon Coast rivers today are between 5-20% of historic levels. Since the 1980s, restoration of freshwater habitat has become a common practice in the attempt to recover Pacific salmon populations. I used two databases, the Oregon Watershed Restoration Inventory, and the Salmon Recovery Tracker, to analyze habitat restoration and coho salmon population recovery on the Oregon Coast. A total of $145,620,716 was spent on 4,173 restoration projects on the Oregon Coast streams from 1997-2012. I hypothesized that the restoration actions had resulted in a significant increase in adult coho abundance on the Oregon Coast. My analysis showed that from 1994 to 2012 only 3 of the 21 independent populations from the ESU, the Alsea, Salmon, and Tillamook had statistically significant recovery. I ran a correlation between the rate of recovery and the amount spent on restoration for each ESU population. The rate of recovery increased as total dollars spent on restoration increased, but it was a very weak relationship. Additional monitoring and more advanced statistical analysis may provide a greater understanding of the relationship between coho salmon and their freshwater habitat.
Lutz, Andrew P., "Recovery of Oregon Coast Coho Salmon (Onchorhynchus kitsutch) through Restoration of Freshwater Habitats" (2014). Master's Projects. 16.