Influence of Environmental Conditions on Assessment of Fish Communities in Two Lake Erie Coastal Wetlands
Date of Award
Water exchanges, Wind, Water level, Temperature, Dissolved oxygen, Community composition
Wetlands of the Laurentian Great Lakes are diverse ecosystems that support a species rich flora and fauna. Fishes are especially important indicators of wetland productivity and ecological condition. Their distribution is controlled by water quality, water temperature and dissolved oxygen concentration and local habitat (depth, substrate, and local vegetation). Thus, weather-driven exchanges of water between a coastal wetland and the adjacent lake can influence the estimates of the composition and relative abundance of fishes.
I investigated the interactions among wind metrics and water level, water temperature and dissolved oxygen in two Lake Erie protected wetlands with fish abundance and community composition estimated from daily fyke net catches through the course of a summer. Water level and water temperature positively correlated with several wind metrics such as the strength of wind blowing towards the shore. However, dissolved oxygen was positively correlated with only the change in water level over the course of sampling. Differences in environmental factors may have influenced the variation in fish communities between the sampling sites. However, the species richness, genus richness, and percentage of fishes found dead in nets were positively associated with the duration of hypoxia (dissolved oxygen <4 mg/L) and minimum daily water temperature but not with amplitude of water level change. Fish abundance and species richness estimates on any day are directly associated with prevailing in-wetland conditions, which are indirectly associated with weather features.
Tuck, Nathan, "Influence of Environmental Conditions on Assessment of Fish Communities in Two Lake Erie Coastal Wetlands" (2021). Electronic Theses and Dissertations. 8657.