Oregon chub (Oregonichthys crameri) are small minnows that exist only in the Willamette Valley of western Oregon. This species was formerly distributed throughout the Willamette Basin in off-channel habitats, such as beaver ponds, oxbows, backwater sloughs, and flooded marshes.

In the last hundred years, these habitats have disappeared because of changes in seasonal flows resulting from the construction of dams, channelization of the Willamette River and its tributaries, and draining of wetlands. The loss of habitat, combined with the introduction of non-native fish, resulted in a sharp decline in Oregon chub abundance and a 1993 federal listing as an endangered species.

Since 1991, the Oregon Department of Fish and Wildlife has conducted surveys to collect information on the distribution and abundance of Oregon chub, the characteristics of historic Oregon chub habitats, the presence of non-native and native species in these habitats, the characteristics of potential introduction sites, and the evaluation of Oregon chub introductions. Because of numerous successful introductions and the discovery of new populations, Oregon chub met the criteria to change its status from endangered to threatened in 2007. The U.S. Fish and Wildlife Service removed the chub from the endangered list completely in 2015, making it the first fish ever to be delisted because of its recovery. Due to their small size and secretive behavior, Oregon chub has had little social or economic impact.