The distribution of Topeka shiner Notropis topeka has declined across its historic range and was listed as endangered under the Endangered Species Act in 1998. In Iowa, the habitat associations of this imperiled fish are not well understood. Our goals were to understand the current distribution and identify abiotic and biotic factors associated with the occurrence of Topeka shiners in stream and off-channel habitats of west-central Iowa. Fish assemblages and habitat characteristics were sampled in 67 stream and 27 off-channel sites during 2010 – 2011. Topeka shiners were found in 52% off-channel sites, but only 9% of stream sites, supporting the hypothesis that off-channel habitats are an important component of their life history. When compared to prior distributions, our results indicated a recent reduction in the distribution of Topeka shiners in Iowa. Fish assemblages in stream sites Corresponding author: bbakevich@gmail.com Department of Natural Resource Ecology and Management, Iowa State University U.S. Geological Survey, Iowa Cooperative Fish and Wildlife Research Unit, Department of Natural Resource Ecology and Management, Iowa State University U.S. Geological Survey, Idaho Cooperative Fish and Wildlife Research Unit, Department of Fish and Wildlife Resources, University of Idaho 4