2026-09-21T02:04:38Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/116132 2023-07-11 col_2142_5131 col_2142_14737 com_2142_5130 com_2142_690 com_2142_397

Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2024-08-01 The student, Courtney Weldon, accepted the attached license on 2022-07-22 at 10:32. The student, Courtney Weldon, submitted this Thesis for approval on 2022-07-22 at 10:48. This Thesis was approved for publication on 2022-07-22 at 11:44. DSpace SAF Submission Ingestion Package generated from Vireo submission #18422 on 2022-11-15 at 21:40:44 Chick, John H Lamer, James T Suski, Cory Brawn, Jeffrey 2022-08 application/pdf en text Small-bodied fish response to Environmental Pool Management in Pool 26 of the Mississippi River Weldon, Courtney R. 2022-07-22 EPM small-bodied fishes drawdown throw trap Seasonal drawdowns of water levels in the Upper Mississippi River System (UMRS), known as Environmental Pool Management (EPM), have been performed since 1994 to harden sediments in backwater lakes to promote the growth of emergent vegetation within the Pools that would otherwise not have vegetation. I used a 1.0 m2 throw trap to sample small-bodied fishes in emergent vegetation within several backwater habitats where EPM had been successful in hardening sediments and producing vegetation. I also collected a representative taxon of macroinvertebrates that were captured in the throw traps, and measured dissolved oxygen, conductivity, and depth for each sample. I analyzed the frequency of occurrence of fishes and species richness among sampling locations. Western Mosquitofish were the most frequently caught fish across all the backwaters, and Ellis Bay was the location with the highest species richness. I compared fish density across sampling locations and mean vegetation biomass from each location. I found an inverse relationship between vegetation biomass and fish density. This suggests that highly vegetated areas in the shallow, no-flow backwater habitats may not be suitable to many fish species. Additional sampling across different year conditions and Pools within the UMRS should be considered going forward to truly understand how fish are responding to EPM-produced vegetation Thesis eng https://hdl.handle.net/2142/116132 Copyright 2022 Courtney Weldon M.S. Thesis Natural Res & Env Sciences University of Illinois at Urbana-Champaign Natural Res & Env Sci