Effects of Trout Introduction on Community Assemblage and Behavior of Native Fish in the Missouri Ozarks

Salmonids have been introduced to Ozark streams since 1878 with few studies to date investigating the effects of trout introduction on native fish. Fish communities were sampled in the fall of 2013 to assess potential impacts of trout introduction on community assemblage and behavior of native fish. An index of biotic integrity (IBI) was used to compare assemblages between sites of trout introduction and contemporaneous controls. Habitat and water temperature data were collected throughout 2012 and 2013 for all streams sampled to assess influences of these variables on fish assemblages and behavior. Results indicated that streams receiving high densities of trout had lower IBI scores than controls. However, water temperature may have influenced this observation due to streams receiving high densities of trout having colder and less variable water temperature. Results of the behavioral study indicate that trout introduction had an effect on the flight initiation distance, a proxy of wariness, of rainbow darters, Etheostoma caeruleum, and orange throat darters, Etheostoma spectabile. The increased wariness observed in these species in trout streams could have long-term fitness consequences for these species.

Name thesis:degree_name

Master of Science in Biology

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Biology

Year

2014

Author dc:creator

• Johnson, Joseph Tyler

Contributors dc:contributor

• Daniel Beckman

• native fish
• trout introduction
• diversity
• flight initiation distance
• Ozarks
• Biology

Statement dc:rights

• © Joseph Tyler Johnson

Repository record dc:identifier

https://bearworks.missouristate.edu/theses/1331

OAI identifier oai:identifier

oai:bearworks.missouristate.edu:theses-2332