Stream and Lake Environmental Effects on Morphology in an Introduced Population of Brook Trout

Abstract

Biodiversity of wild populations contributes to the stable functioning of an ecosystem, yet we still do not fully understand how environmental variation affects the origins of biodiversity via natural selection. Recently introduced populations into novel but pristine environments provide an ideal case study to investigate how rapid evolution in variable habitats occurs. This project will study the brook trout (Salvelinas fontinalis) population that was planted within the Salmon Creek Reservoir in Juneau, Alaska in the early 19th century. The purpose of this project is to achieve an understanding of how environment and morphology of brook trout interact, and whether this new habitat is leading to new phenotypes within this previously unstudied population of brook trout. Studies of other native fish species show that divergence in body shape between stream and lake populations can occur over long periods of time, typically resulting in more streamlined body shapes in stream populations.