Mercado Fluvial: fish market yesterday- so much action happening!!
Creating secure habitats for the conservation of native inland fish has become a common fisheries management practice in recent years. Most commonly, the goals of these efforts are to restore and preserve native fish biodiversity through the exclusion and removal of non-native fish and the reintroduction of genetically unaltered native species. The need for projects of this nature is largely driven by competition, predation, and/or hybridization by non-native fish; however, other factors including habitat alteration, disease, and climate change may also contribute to the need for action. A common project model that has evolved and become widely used follows three basic steps: 1) ensure isolation of the project area, 2) completely remove all non-native species, and 3) re-introduce genetically unaltered native species. The body of scientific information that has accrued around this model, conventional wisdom, and on-the-ground experience is used to carry out the project.
In the park’s early history, non-native trout were readily stocked into park waters to provide additional fishing opportunities for visitors. Over the last century, these non-native trout have eroded native trout populations to a small fraction of their historic range. Once occupying hundreds of stream kilometers, indigenous westslope cutthroat trout now occupy only 2 km (1.2 mi.) of streams in the Grayling Creek drainage, while fluvial grayling disappeared entirely from the park by 1934. As park biologists, we have worked diligently to restore these native fish back into their historic ranges using approaches described above. Over the past decade, genetically pure westslope cutthroat trout have been reintroduced into the headwaters of Specimen and Grayling creeks, with a local brood source being developed in the Goose Lake complex. Our restoration efforts have added 74 km (46 mi.) of stream that are now occupied by native westslope cutthroat trout and/or fluvial grayling. The grayling introduced to upper Grayling Creek in 2015 were the first fluvial grayling to swim in park waters in more than 80 years. Future projects for westslope cutthroat trout and fluvial grayling include native fish restoration in North Fork Specimen and Cougar creeks as well as the upper Gibbon River. Once these projects are completed, an additional 61 km (38 mi.) of stream will be restored to native fish. As the NPS enters its next century, we continue to work to preserve and protect native fishes of Yellowstone for future generations.
The upper Gibbon River (above Virginia Cascades) and connecting lakes in YNP will be used as a refuge for native fish threatened with a warming climate. The refuge would include 16 km (10 mi.) of stream, three fish bearing lakes totaling 92 ha (228 surface ac), and extensive tributary networks, representing the largest and most logistically feasible location for westslope cutthroat trout and fluvial grayling restoration in the species’ historic range (figure 1). High-elevation aquatic systems, such as the upper Gibbon River, may be the only chance to protect sensitive, cold water species such as westslope cutthroat trout and fluvial grayling against climate change. The project will begin with the removal of fish from Ice Lake. The project will continue with the complete removal of fish from the Gibbon River above Virginia Cascades upstream to Grebe Lake. Westslope cutthroat trout and fluvial grayling will be introduced immediately afterwards. This project is expected to take three years to complete.
Fluvial-Fish Species-Richness Model
Genetics, fluvial fish and drought