Contract Description:
This project has four long term objectives: 1) ensure that the sample design and estimation methods for producing tribal catch estimates are statistically valid, 2) make accurate harvest data readily available for decision making, 3) improve the transparency and dissemination of catch estimates, with associated variances, and 4) account for the uncertainty of estimates in management. Ultimately, this project will determine and formalize statistically valid sampling protocols for tribal harvest estimates throughout the Columbia Basin.
Tribal harvest in the mainstem is comprised of commercial gillnet, ceremonial and subsistence gillnet, and commercial and subsistence platform fisheries (using dip and hoop nets, and hook and line). The majority of tribal harvest and catch sampling occur in the Zone 6 commercial gillnet fishery. Catches in the fall gillnet fishery are comprised of bright and tule fall Chinook, A and B steelhead, and coho. Fish ticket data do not represent the entire catch, due to direct “over-the-bank” sales and subsistence use. Therefore, catch is estimated using creel census techniques, wherein an estimate of catch rate is combined with effort data to estimate total catch of each species and run. In 2010, this project focused on the creel census catch sampling for this fishery, including documentation of sampling methods and historical catch estimates. This project should not be confused with project 200850200, Increased Zone 6 Tribal Fishery Monitoring, which actually involves the increased sampling. Project 200850800 is to improve the sampling design and estimation methods of the sampling programs, and document and recommend improved sampling protocols. However, the two programs are closely related, with this project developing the improved sampling protocols, and 200850200 providing resources for additional sampling efforts.
In 2011, Project 200850200 will explore the feasibility of expanding the creel census sampling for catch data to include both sampling for PIT tag data using handheld Psion data loggers (consistent with equipment used by ODFW), and collection of genetic samples. The hand held data loggers can also be used to log the creel census sampling data already collected. Preprinted bar code labels, in conjunction with bar code readers on the handheld data loggers may be used to manage the physical labeling of genetic samples and associating labeled samples with genetic sampling data. In order to fully deploy the data loggers, Windows mobile software applications must be developed for entering each set of sampling data: 1) the current creel census data, 2) the sample data associated with the PIT tag detections, so that the information for subsequent analyses using those detections will be available, and 3) the genetic sampling data. In 2011, Project 200850800 will facilitate Project 200850200 by developing these software applications, and helping train tribal samplers in best practices for using the PIT tag detectors, as well as using the software applications. A system for synchronizing, verifying, and distributing the data for timely use will also be developed. Ultimately, this will allow the creel census and PIT tag data to be synchronized with a secure online database. The creel census data can then be automatically collated, error-checked, analyzed, and summarized, to provide the Technical Advisory Committee of the Columbia River Compact with real-time weekly catch estimates.
Weekly harvest management decisions are based on the Zone 6 catch estimates. Compliance with management agreements, including US v. Oregon and the Pacific Salmon Treaty, is evaluated based on these estimates. Catch estimates are also critical in estimating productivity and optimal escapement. It is important to understand the uncertainty associated with the estimates and to use available resources in the most effective way possible to obtain estimates that are as precise and accurate as possible. This project will be completed by Marianne McClure, in the CRITFC offices and throughout the fishing areas, in coordination with tribal staff implementing catch sampling programs.