According to the Iowa DNR, 64 different species of fish have been identified in the Upper Iowa River (UIR) Watershed. This includes 13 different game fish species. They note that Smallmouth and Walleye are the most common warm water game species, while Brook, Brown, and Rainbow Trout are common cold water game species often associated with the cold water tributaries of the UIR and, under certain conditions, segments of the UIR itself.
The last population of native Iowa Brook Trout in Iowa were found in the UIR Watershed in South Pine Creek, which is a small tributary in the Canoe Creek Subwatershed. This strain of Brook Trout was confirmed unique to Iowa through an Iowa DNR Fisheries genetic testing project completed in 2018. Although the South Pine Creek Brook Trout genetics are similar to other strains of Brook Trout from the Driftless Area of Wisconsin and Minnesota, it is unique in its own right. Since the holdout Brook Trout population was identified decades ago, Iowa DNR Fishery and Hatchery personnel have hatched, reared and stocked this genetically distinct strain into other cold water stream segments in Northeast Iowa, primarily into small, isolated, tributaries in the UIR Watershed where they will not be out competed by Rainbow and Brown Trout. Brook Trout are particularly sensitive to temperature and water quality. The Iowa DNR notes that Brook Trout are, “seldom found in water with temperatures higher than 50-60 degrees. Needing the coldest and cleanest of stream conditions, the Brook Trout is highly sensitive to pollution, sedimentation and water quality degradation.” The Iowa DNR’s success with reintroduction of Brook Trout, which is the most sensitive of the three trout species in the UIR Watershed, and the only native trout species to Iowa, Brown Trout and Rainbow Trout are both introduced species, is in part due to the efforts of private and public partners and landowners to restore water quality and watershed health. Additional information on Brook Trout can be found here.
Due to the conservation and restoration efforts of private and public partners and landowners, natural reproduction of trout, primarily Brown and Rainbow Trout, has been established to 19 segments of stream in the UIR. Some experts now believe that the entire UIR Watershed may be functioning as a coldwater system, with trout moving in and out streams and the UIR at various times of year.
The Iowa DNR notes that along with the native Brook Trout, there are two species of sculpin represented whose presence indicates a high quality cold water stream. The American Brook Lamprey, Black Redhorse, and Burbot are threatened species found within the watershed (571 IAC 77.2(2) (2015)). Besides these three, there are an additional 18 fish species listed as species of greatest conservation need.
The economic impact of trout in the UIR Watershed, including the sensitive Brook Trout, is significant. In 2016, Trout Unlimited commissioned a study of the economic impact of trout fishing and stream restoration activities in the four-state Driftless Area, including the UIR Watershed, which has more miles of coldwater trout streams than any watershed in Iowa. TU notes that, “the purpose of the study was to estimate the economic impact of trout fishing and stream restoration activities, summarize information on angler demographics and opinions, and identify characteristics of a healthy “Trout Economy.”” The study measured “new spending in the region” that occurred “as a result of an event or feature such as trout streams, as opposed to spending that would have occurred anyway”. Additional information about the economic impact of trout in the Driftless Area can be found here.
To find more information about fish species located in the Upper Iowa River Watershed check out the Iowa DNR Biological Monitoring and Assessment Database.