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Population introductions and reintroductions have become a common tool for conserving threatened species, but oftentimes introduced populations have reduced the genetic diversity compared with the source population they were founded from. Population introductions played an important role in the recovery of the Oregon Chub Oregonichthys crameri, a small floodplainminnow found in western Oregon. Unlike many introduction efforts, introduced populations of Oregon Chub were founded using large numbers of individuals (hundreds in many cases) and each population had a unique introduction history (e.g., number of founders, source populations selected, duration of the introduction effort). We used microsatellite loci to examine 13 introduced populations and their respective sources to evaluate how well the introduction program captured genetic diversity present in the wild populations. Genetic variation was reduced by roughly 25% in one introduced population, and three introduced populations showed evidence of a genetic bottleneck due to heterozygote excess. Populations introduced from multiple sources had greater genetic diversity than populations from a single source. When multiple source populations were used, all source populations contributed genetic material to the introduced population, though the proportional contribution from each source population varied. Using correlation analyses and general linearmodels, we explored the relationship between introduction history variables and genetic diversity. Our top-ranked models included genetic diversity in the source population, and this variable had the highest variable importance weight (0.999), but the number of founders and the number of source populations were also important. Overall, the Oregon Chub introduction program was highly successful at capturing the genetic variation observed in natural populations. Results of this study will be useful for planning future population introductions for Oregon Chub and other species of conservation concern. [ABSTRACT FROM AUTHOR]

Conservation banks are permanently protected lands that contain habitat elements which may be critical to the protection and recovery of federally-listed species under the Endangered Species Act. These banks are managed in perpetuity and used to mitigate impacts occurring elsewhere to the species' habitat. We developed a species crediting methodology to assess conservation credits and debits for the endangered Oregon chub (Oregonichthys crameri) to support conservation banking. Our methodology is based on prior studies assessing relationships between population abundance and habitat parameters for the species. The methodology also incorporates ratings for piscivory risk, site location, and the abundance and status of existing and proximal populations. Our approach assigns more credits to functioning bank sites that support abundant, stable populations and requires more credits when impacted sites negatively affect these populations. Examples show the credit value calculations for determining baseline conditions and for assessing impacts to species habitat. Additional examples illustrate the incentives for creating habitats that support abundant, stable populations and the incentives for reducing the severity and duration of impacts to habitats. As the demand for economic development of prime fish habitat increases and as more conservation banks are developed, managers may benefit by developing similar crediting methodologies to promote adequate compensatory conservation for imperiled species. [ABSTRACT FROM AUTHOR]

We describe the isolation and development of 16 polymorphic tetranucleotide microsatellite loci for the endangered Oregon chub ( Oregonichthys crameri). Two loci appear to be duplicated. For the remaining 14 loci, we observed between three and 19 alleles per locus in a sample of 42 fish. Thirteen of these loci were also polymorphic in the closely related Umpqua chub ( O. kalawatseti). These loci will aid in our understanding of the molecular ecology and conservation of these two species. [ABSTRACT FROM AUTHOR]

This article describes the Oregon Chub fish (Oregonichthys crameri) (Snyder, 1908) (Cyprinidae) one of the threatened fishes of the world. This fish is protected by state law in Oregon. It is listed as a species of concern under the U.S. Endangered Species Act. Its features are described in detail and it is compared with other species with which it is associated. The author discusses the species' entire range and population distributions. He also describes how the fish utilizes various habitats during different seasons. The fish's diet is described as are the environmental conditions it prefers or tolerates. Interspecies competition is discussed along with preferred substrates. The fish's life-cycle is described and threats are listed together with conservation actions and recommendations.

The article presents the author's views on the Endangered Species Act (ESA) announced by the U.S. in 2015 that had not listed sage grouse and oregon chub, and mentions topics including federal regulations that protect oregon from human ill practices, loss of natural habitats, and geomorphology.

The article reports on a February 2014 proposal by the U.S. Fish and Wildlife Service (FWS) to remove the Oregon chub from the endangered species list due to habitat recovery, which would be the first fish to be taken off the list.