Bioenergetic assessment of habitat quality for stream-dwelling cutthroat trout (Oncorhynchus clarkii bouvieri) with implications for climate change and nutrient supplementation

• Published in: Canadian journal of fisheries and aquatic sciences 2010-02, Vol.67 (2), p.371-385
• Main Authors: Jenkins, Amy R, Keeley, Ernest R
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal reproduction; Animal, plant and microbial ecology; Applied ecology; Bioenergetics; Biological and medical sciences; Brackish; Climate change; Cutthroat trout; Distribution; Environmental quality; Evaluation; Exploitation and management of natural biological resources (hunting, fishing and exploited populations survey, etc.); Fisheries; Food and nutrition; Fresh water ecosystems; Freshwater; Fundamental and applied biological sciences. Psychology; Growing season; Habitat (Ecology); Habitat changes; Habitats; Marine; Oncorhynchus; Oncorhynchus clarkii; Oncorhynchus clarkii bouvieri; Oncorhynchus clarkii clarkii; Physiological aspects; Salmon; Spatial behavior in animals; Studies; Synecology; Trout
• ISSN: 0706-652X; 1205-7533
• DOI: 10.1139/F09-193

We used a bioenergetic model to determine if cutthroat trout ( Oncorhynchus clarkii bouvieri ) abundance was related to net energy intake rates (NEI) and the proportion of suitable habitat and to evaluate potential changes in habitat quality due to climate change and stream fertilization efforts. We conducted monthly sampling of cutthroat trout, invertebrate drift, and physical habitat features in pool and riffle habitats. Fish in this study selected foraging positions that enabled them to maximize NEI, and most fish were capable of sustaining high growth rates from July to September. Mean NEI and the proportion of suitable habitat at sites were greater in pools relative to riffle habitats and declined from July to October, primarily due to a decline in temperature over the four months. Cutthroat trout biomass was significantly related to NEI and the proportion of suitable habitat at a site. Model simulations indicated that climate change might reduce habitat quality for small-bodied trout, while extending the growing season for larger fish. Increased food abundance provided only marginal changes to model outcomes, whereas reductions in food significantly reduced habitat quality.