Undergraduate Honors Theses

Thesis Defended

Spring 2013

Document Type



Ecology and Evolutionary Biology

First Advisor

Dr. Suzanne Nelson


Not only is water critical for human needs, but also for providing habitat for aquatic organisms. The Clean Water Act (CWA) was passed in 1972 and requires protection of chemical, physical, and biological features of our nation’s waters to protect wildlife as well as maintain quality for human consumption. However, there is a lack of research to completely understand food availability for fish. Using a quantifiable food analysis method developed in this paper caloric content of macroinvertebrates was analyzed at two different altitude sites on Boulder Creek, Colorado, USA. By drying and weighing a representative sample of invertebrates identified at each site, caloric values were calculated for food availability in each stream section. Habitat type (shallow, steep river sections known as riffles vs. deep, flat river sections known as pools), and depth was compared with respect to caloric content. It was hypothesized that flow regularity below a reservoir would result in greater macroinvertebrate calories, and that caloric content would be greater in riffle habitats due to favorable habitat conditions. Results supported this hypothesis in that the greatest caloric content was found at low altitude sites, in riffle habitats, and at shallow depths. These results may be the product of passive macroinvertebrate movement as downstream drift, or maybe due to flow regulation below a reservoir. This work offers a novel method for quantifying stream energetics and could potentially benefit multiple stakeholders interested in stream research and water management.