Project overview:

Snake River salmonid populations have experienced significant decline in population numbers over the past five decades with chinook salmon and steelhead now listed as a threatened species under the Endangered Species Act (ESA).  In spite of a considerable habitat enhancement, population protection and monitoring effort by management agencies, recovery of these populations has not been successful.  Therefore, a genetic resource management approach using cryogenic technology to preserve gametes has been implemented for those salmonid populations (conservation units) at low levels of abundance and high risk of extirpation.  The goals of the gamete preservation project are 1) to preserve and maintain salmonid population genetic diversity, 2) as an insurance policy against population collapse and extirpation, 3) for ongoing artificial propagation programs and 4) to preserve genetic material for future management options.   The NMFS draft recovery plan states that "the conservation of local populations or stocks of Pacific salmon and the preservation of their genetic resources is an important goal".

NPT initiated chinook salmon cryopreservation activities in 1992 in response to the severely reduced returns of adult chinook salmon in Big Creek (a tributary of the Middle Fork Salmon River).  In subsequent years, a more comprehensive gene banking effort was initiated including collections from additional chinook spawning aggregates in the Snake River basin and collections from steelhead populations in the region.  By collecting from numerous populations of spring and summer chinook salmon and steelhead across the entire Snake River basin, this project aims to preserve the greatest amount of endemic salmonid diversity.  


PROJECT DESCRIPTION

The germplasm repository provides long-term storage for cryopreserved gametes.  Although only male gametes can be cryopreserved, this project preserves the genetic diversity of these stocks and provides management options for future species recovery actions.  NPT efforts have focused on preserving salmon and steelhead gametes from the major river subbasins in the Snake River basin.  

This approach seeks to preserve and maintain genetic diversity from artificially propagated and natural salmonid populations utilizing cryogenic technologies.  Specifically, this project preserves male gametes from ongoing artificial propagation programs and natural populations of ESA-listed Snake River chinook salmon and steelhead.  The artificial propagation programs include, but are not limited to, the Lower Snake River Compensation Plan hatchery supplementation programs on the Imnaha River, South Fork Salmon River, and at the Sawtooth Hatchery and the Idaho Power Company maintained mitigation hatchery programs at Oxbow Hatchery, Rapid River Hatchery and Pahsimeroi Hatchery.  Additionally, gametes are preserved and housed in the repository from Bonneville Power Administration (BPA)-funded captive broodstock programs in the Salmon and Grande Ronde subbasins  Cryopreservation activities would also occur on salmonid populations from streams with ongoing or planned conventional hatchery programs such as Johnson Creek, Lostine River, Catherine Creek and the upper Grande Ronde River.  These samples would be available for use with the ongoing hatchery supplementation programs as needed with a portion of all samples being gene banked for future use.  Targeted wild/natural populations of chinook salmon and steelhead include those in the Salmon, Imnaha, Grand Ronde and Clearwater River subbasins.  Specific sampling locatings include Lake Creek, Sechesh River and South Fork of the Salmon River in the South Fork of the Salmon River drainage, Big Creek, Marsh Creek, Capehorn Creek and other tributaries in the Middle Fork of the Salmon River drainage, the main stem Salmon River and tributaries, the Imnaha River and tributaries, the Grand Ronde River and Tributaries and the Clearwater River and Tributaries.  Future collections will include these sites plus additional sites in the Salmon, Imnaha, Grand Ronde, Clearwater and Tuccanon River subbasins.  

Gamete samples are transported to laboratories at WSU and UI for cryogenic freezing (the freezing procedure is available from William Young, project leader).  Redundant gamete repositories are housed at each university to prevent complete loss of the collection in case of a catostrophic event.  Repository maintainance is conducted through subcontracts with university personnel.  The repository is also available for other management agencies to contribute gamete samples from other regions and species.  The space used to house these samples does not increase the cost of repository maintainance, but rather, greatly increases the value of this project to the region.

RM & E activities are used to assess the effectiveness of the project. Biological data is collected from all sampled fish and entered into a comprehensive database. Tissue samples are collected from each fish and a subset of these are genotyped annually.  Genetic data is used to monitor and evaluate the effectiveness of the collections and guide future collections.  Annual fertility trials are conducted to assess the effectiveness of the collection, handling and freezing protocols used in the previous year.  These data will guide future decisions and indicate areas of research that can increase project effectiveness.

In addition to gamete collections, this project investigates novel collection, handling and freezing techniques that will assist this project as well as future gene consevation programs.  Experiments include comparing the effectiveness of new gamete extenders, freezing and thawing rates and fish and sperm viability.

To date, male gametes from 2794 Snake River sp/su Chinook salmon, 1368 Snake River steelhead, 22 Kootenai River male white sturgeon and 9 Kootenai River male burbot are preserved in the repository.