A Comprehensive Examination of the Wind River Range: Does Hybridization Effect Dietary Partitioning?

Rebecca Hinds, Lucia Combrink, Catherine Wagner, Department of Botany, University of Wyoming 82071.

The Wind River Range, located in Western Wyoming, is an understudied, geographically unique system containing alpine freshwater lakes, which historically contained no fish. Non-sympatric species of fish- Yellowstone Cutthroat Trout and Golden Trout were stocked by the Wyoming Game and Fish Department in the mid-1900’s for recreational fishing. These predators changed the ecosystems of the lakes they were introduced into, presenting a novel and unique research opportunity. According to the ecological theory of competitive exclusion, populations using the same resources should partition available resources, or local extinction of one species may occur. We have previously investigated dietary trends in fish to examine partitioning roles in this system, and we will investigate the hybridization occurring among the fish. Dietary analysis was performed using visual stomach content analysis and stable isotope analysis. Dietary analysis determined that hybrids demonstrate a strong preference for terrestrial prey items, however these lakes are covered with ice for most of the year. Stable isotopic analysis allowed us to see how dietary trends shift throughout the year by comparing abundance of Carbon and Nitrogen in muscle samples. The results from the isotopic analysis demonstrated significant dietary overlap of Yellowstone Cutthroat Trout and Golden Trout. The results from these analyses yielded inconclusive results regarding our hypothesis; we cannot determine if these fish experienced dietary partitioning using prior data alone. Looking forward, we will use next generation sequencing procedures to determine the genetic composition of these fish. This will provide us with information regarding the degree of hybridization and the tempo of evolution in these lakes. Many lakes in the Wind River Range share characteristics, providing opportunity for a large scale study on ecological adaptations of introduced predators to alpine oligotrophic lakes.

Additional Abstract Information

Presenter: Rebecca Hinds

Institution: University of Wyoming

Type: Poster

Subject: Biology

Status: Approved

Time and Location

Session: Poster 3
Date/Time: Mon 4:30pm-5:30pm
Session Number: 3165