Return of Topeka Shiner (Notropis topeka) to Restored Oxbows in the White Fox Creek Watershed, Iowa, USA

Abstract

The Topeka shiner (Notropis topeka), a federally endangered species of minnow endemic to the Great Plains region of the central United States, has experienced widespread population declines resulting from loss of habitat. N. topeka habitat in Iowa, most notably oxbow wetlands, was mostly eliminated from the landscape during European settlement and agriculturalization of the region. Over the last two decades, restoration of oxbow habitats in Iowa has been increasing. Restorations provide critical habitat for N. topeka and regenerate a variety of ecosystem services that benefit many species of flora and fauna. There are signs that restoration of oxbow ecosystems is generating positive impacts on N. topeka recovery. Recent studies revealed that N. topeka populations are recovering within a few Iowa watersheds. In the investigation described here, we report the 2020 discovery of two N. topeka specimens in different restored oxbows within the White Fox Creek HUC10 of north central Iowa. Prior to these collections, the species had been undetected within this basin for 36 years. (It is possible that N. topeka persisted within the basin but remained undetected during sampling efforts.) Multiple oxbows have been restored within the White Fox Creek basin in recent years, and significant source populations of N. topeka can be found in nearby watersheds. These collections suggest that as oxbow restorations continue and land stewardship practices improve, N. topeka populations might recover and become reestablished within the historical range.