The Topeka Shiner: Shining a Spotlight on an Iowa Success Story
By Aleshia Kenney
Fish and Wildlife Biologist
Partners for Fish and Wildlife Program
Rock Island Field ES Office
What started out as just an idea with a few skeptical landowners in the early 2000s has now turned into a true success story in Iowa. Blending the U.S. Fish and Wildlife Service’s Partners for Fish and Wildlife Program with endangered species habitat restorations has served as a steppingstone toward recovery for the endangered Topeka shiner (Notropis Topeka).
The Topeka shiner, a small minnow listed as federally endangered in 1998, was once found in many streams and rivers throughout Iowa. It declined as conversion of Iowa’s native prairies to agriculture degraded prairie streams and important in-stream habitats. Modern practices to improve drainage and maximize planted acreage continue to threaten the species. Conserving this fish in Iowa requires maintaining and expanding existing populations.
Because little was known about Topeka shiner life history and habitat use when it was first listed, initial recovery actions focused on research. Studies conducted by Kansas State University, Iowa State University, South Dakota State University, and others delivered critical information on spawning behavior and diet. However, it was the discovery that this small prairie fish often utilized off-channel habitats that has made all the difference.
Pre-settlement Iowa was covered in prairie. Prairie streams naturally meandered over this landscape, creating cut-offs and meander scars on the outside loops of the mainstream channel. Over time, these loops became U-shaped ponds known as oxbows, which reconnected to the stream only during high water. Oxbows, which are off-channel ponds, provided the perfect, quiet, pool-like habitat that Topeka shiners require for spawning and rearing. To improve drainage on farmlands, naturally meandering prairie streams have been straightened and channelized, halting the creation of oxbows and other natural pools found within streams. Old oxbows have filled with sediment and are no longer deep enough to support fish throughout the year. Fish that require off-channel habitats for all, or part, of their life cycle (such as the Topeka shiner) move into these oxbows during spring flood events but cannot survive through the summer months because the oxbows dry up.
In Iowa, landscapes surrounding the watersheds that still support Topeka shiners are littered with old oxbow scars. We recognized that these scars represented potentially restorable habitat; all that was needed was landowners willing to do the restorations. In 2000, the Service’s Rock Island Ecological Services Field Office utilized special recovery funds and partnered with the Iowa Natural Heritage Foundation to begin discussing oxbow restoration with private landowners who owned property with potentially restorable Topeka shiner habitat. Initially, many landowners met us with skepticism, but a few conservation-minded landowners decided to give oxbow restoration a chance. Restoration required digging out sediment that had built up in the oxbow to increase its depth and capacity to hold water throughout the year.
To date, the Service, through the Partners for Fish and Wildlife Program and Ecological Services Program, along with our partners the Iowa Natural Heritage Foundation, the Natural Resources Conservation Service, the Iowa Department of Natural Resources and The Nature Conservancy, have restored 53 oxbows in the North Raccoon River watershed and one in the Boone River watershed. These restorations have had outstanding results.
Many of the restored oxbows now support Topeka shiners, and reproduction of Topeka shiners has been documented. In 2009, researchers with the Service found 354 Topeka shiners in one restored oxbow alone. More restoration projects for both the Raccoon River and Boone River watersheds are planned and many neighboring landowners have expressed interest in restoring habitat for the Topeka shiner on their properties after learning of the success of previous restoration projects.
Oxbow restoration is a major step towards recovery of the Topeka shiner in Iowa. Oxbows provide sustainable habitat in a landscape that has been dramatically changed over the years. In the Service’s 2009 five-year review of the Topeka shiner, the three biggest threats listed for the species in Iowa were row crop agriculture/grassland conversion, climate change and dams/changes to stream hydrology. Oxbow restorations, in varying degrees, help reduce all three of these threats. After an oxbow is restored, grassland is also restored, by planting the surrounding area back to native prairie.
Additionally, the drought experienced during the summer of 2012, a precursor of the future as the climate continues warming, illustrated clearly that increased available habitat is necessary for the Topeka shiner to survive. Restored oxbows create a more resilient landscape that will, we hope, provide enough sustainable habitats to allow the species to persist. Oxbows also help to provide habitat lost from changes to stream hydrology by creating off-channel pools that mimic habitat that has been lost within the stream due to factors like channelization.
Private landowners are eager to work with the Service and other partners to restore oxbows. In addition to basic water quality benefits, these wetlands produce abundant quantities of food for amphibians and reptiles, and habitat for migrating birds, especially waterfowl. Even small sites, much less than an acre, can produce hundreds of frogs, toads and salamanders. Typical of most conservation actions for endangered species, the benefits of oxbow restorations go far beyond Topeka shiner recovery.