Adipose fin clipping of steelhead

It's not always NOAA who determines if a fish caught in a fishery is listed under the Endangered Species Act. NOAA does assess the potenital impacts of proposed fisheries and determines what levels of takes in fisheries are allowable (do not cause further harm to the listed fish). Once an unmarked fish has been caught, it's typically up to the states and tribes and their sampling programs to determine if the fish was wild or hatchery. In Idaho (and the entire Snake River basin) all hatchery salmon and steelhead that are released are genetically marked, a program called Parental Based Tagging. The genetic identity of all the parent fish that produce the offspring each year is known so when those offspring return from the ocean as adult fish biologists can analyze a genetic sample from a fish and determine if the parents were a hatchery fish or a wild (typically listed) fish. It's very similar to human genetics testing. Idaho Fish and Game is using these genetic techniques to analyze steelhead caught in fisheries from the mouth of The Columbia River upstream to lower Granite Dam and steelhead and salmon caught in all Idaho sport fisheries. Native Americans are allowed to possess ESA-listed fish because their fisheries typically are non-selective, meaning the harvest techniques used are lethal to the fish thus they cannot sort through the catch and release some fish. However, their fisheries can only occur within the allowable impacts determined by NOAA - that is they can not exceed a certain level of impacts. Sport fisheries also result in some mortality of listed fish; not all fish that are released survival after release and there also are ESA limits on allowable mortality for sport fisheries.