Degree

Master of Science (MS)

Department

Biology

Document Type

Thesis

Abstract

Mosquitoes are a primary transmitter of vector-borne disease, and their larvae can thrive within shallow pools of stagnant water. Rainwater drainage ditches are a common sight in many communities, and in Louisiana, they are dually used as outlets for onsite residential wastewater discharge in neighborhoods disassociated from municipal sewage treatment. However, when discharge systems malfunction, the water becomes uninhabitable to mosquito predators, allowing mosquitoes to thrive. This research examines the predation performance of mosquitofish (Gambusia affinis), sailfin mollies (Poecilia latipinna), and least killifish (Heterandria formosa), the primary biological control agents utilized to combat mosquitoes within ditch communities. Individuals were captured within drainage ditches contaminated with raw effluent (exposed) and those that use municipal water systems (control). Fish were exposed to varying concentrations of effluent water for predation experiments; no differences were found among concentrations or exposure type, but mosquitofish were consistently the most proficient predators of mosquito larvae among the 3 species. Additionally, a 96-hour exposure to effluent did not impact the survival of mosquitofish sourced from two geographically separated Louisiana parishes. We believe that heavy precipitation throughout the course of our study diluted the toxicity of effluent at the source location, minimizing physiological distress to all three species. Our research suggests that the introduction of mosquitofish and other native poeciliids during a wet season would be the most efficient method of biological control to reduce mosquito populations in Louisiana.

Date

13-1-2026

Committee Chair

Emily A. Kane

DOI

https://proquest.com/docview/3292507433

First Committee Member

James S. Albert

Second Committee Member

Mark A. Genung

Download

Included in

Toxicology Commons

Share

COinS