Lower Columbia River Chinook Salmon Tules

Lower Columbia River Chinook salmon have three life history types including a spring run, a fall timed component referred to as tule Chinook, and a late-fall timed component referred to as bright Chinook. From a harvest perspective, tule Chinook are the most problematic. There are large numbers of hatchery tules that are produced to mitigate for the effects of hydropower development. These hatchery fish contribute heavily to fisheries from Alaska to the northern Oregon coast, as well as the lower Columbia River. The wild tule populations are at greatest risk because of the collective effects of hydropower development, habitat degradation, hatcheries, and harvest. Since 1999, when Lower Columbia River Chinook were listed under the Endangered Species Act, the harvest impacts to tule Chinook have been reduced from 80 percent to 37 percent.

In 2012, NOAA Fisheries approved a plan to manage the harvest of tule Chinook using an abundance based harvest strategy. The science leading to this strategy developed over the years since the species’ listing. The documents below chronicle the evolution of reports and decisions leading to NOAA Fisheries’ most recent biological opinion supporting abundance based harvest management of tule Chinook. The 2010 biological opinion provides a summary of the consultation history and the status of the science at that time. The opinion was informed by a life cycle model analysis conducted by the Northwest Fisheries Science Center and outlines tasks designed to answer key questions to inform management decisions. Tasks A through H, as outlined in the 2010 opinion, were addressed through a series of reports. Information from the on-going recovery planning process for the lower Columbia River further informed our consideration of the effects of harvest and the use of an abundance based harvest regime. In 2010, the Pacific Fisheries Management Council formed the Tule Chinook Work Group to consider the option of abundance based management. The work group provided a report to the Council in November 2011 that was subsequently used to develop a specific recommendation for abundance based management to NOAA Fisheries. These events culminated in NOAA Fisheries approval of the Council’s recommendation and the adoption of a 2012 biological opinion.

Supporting Documents

2010 Northwest Fisheries Science Center Life Cycle Model Report(application/pdf, 27.5MB)

Tule Task Reports

Lower Columbia River Recovery Plan for Salmon & Steelhead

Tule Chinook Work Group Report (application/pdf, 1.7MB)