Presentation on theme: "Workshop: Monitoring and Evaluation of Harvest on Columbia River Salmonids July 31- August 1, 2007."— Presentation transcript:
Workshop: Monitoring and Evaluation of Harvest on Columbia River Salmonids July 31- August 1, 2007
Harvest Monitoring Varies by Fishery and Season Three main types of salmon/steelhead fisheries Ceremonial/subsistence permit gillnet Platform/hook and line Commercial Gillnet Sturgeon Fisheries Shad fisheries
Ceremonial/Subsistence Permit Fisheries Primarily spring Chinook fisheries. Each tribe manages fisheries separately. Some tribes monitor fisheries directly and collect some biological data (CWT, etc.). Other tribes require permit holders to report total catches.
The Yakama Nation employs four fishery monitors. (Number of monitors depending on funding) They work full time throughout most of the year. They monitor all four tribes fisheries (except Ceremonial permit fisheries). Nez Perce tribe has had funding to assist in Zone 6 monitoring in some years. Total monitoring effort limited by budget constraints.
Tribal Fishery Monitoring Tasks for Platform/hook and line fisheries Monitors are assigned to three main geographic areas (Cascade Locks, Lone Pine, and below the John Day Dam) Monitors count active gears (active platform sites and or active hook and line gear. Monitors observe active platforms for a set number of hours per shift. Monitors note numbers and species of fish observed and also note any non-observed catch reported by fishers.
Catch Estimation for Platform/Hook and Line Fisheries We assume that platforms are fishing certain numbers of hours and days in each season. We assume that catch is not even between daytime and nighttime fishing. We assume that 10% of the catch occurs outside the three main platform areas. Goal of monitoring 20% of time platforms are fishing. Platform monitoring rates decline during commercial gillnet fisheries.
Catch Estimation for Platform/Hook and Line Fisheries Monitoring data are expanded for total active gears. Expanded for assumed daytime and nighttime hours fished. Catch estimates are made independently for Cascade Locks, Lone Pine and below John Day dam. Catches are expanded for assumed 10% harvest in un- monitored areas. During commercial gillnet periods, platform/hook and line catch is incorporated single weekly harvest estimate.
Net Flights are used to measure commercial gillnet fishing effort
Net Count Methods Flights occur once during each weekly commercial gillnet opening Flights are set to approximately the middle of the opening and begin about at 7:00 AM. Flights always go the same direction. Flights go upstream along the Oregon shore and downstream along the Washington Shore. Nets are counted separately in specific geographic sections of each pool. If two counters are used, counts are averaged.
Assumptions for Net Counts Net counts are an index of fishing effort. Counting in the middle of the fishery observes most nets. Nets are equally visible during any weather or wind condition. Nets are not being put in or removed during counts. Using average counts (if two observers are used) assumes that it is equally likely to overcount as undercount.
Commercial Gillnet Catch Sampling Monitors sample catch at landing points (often in-lieu fishing sites). Data collected on number of fish per net, number of nets sampled, number of times per day nets are checked and number of nets each sampled crew are fishing. Any drift nets sampled are accounted for separately. Summer and fall season steelhead are measured < or 78 cm and presence/absence of Ad-clip. In fall season skin color calls are made for preliminary Bright/tule separation. Data are matched with net flight data and catch estimates are made for each pool separately.
Commercial Gillnet Catch Sampling Monitoring data are expanded based on the net counts and the total length of the fishery. CWT data are used in the fall to make final stock composition estimates. In some years Bonneville sampling data have been used to adjust steelhead wild fish estimates in fall season. Commercial fish ticket data are not directly used except to double check total catch estimate (Ticket sales should always be less than total catch estimate).
Biological Sampling Tribal monitors do not do biological sampling. State samplers sample tribal catch for CWT, scales, and other data at commercial buying stations (often now at In-Lieu fishing sites). Direct to public sales (over-the-bank) and take home fish are not sampled. This assumes the stock composition of direct sales and take home fish is close to that of fish sold to buyers and/or that it is a small enough portion of total catch that it does not make a difference.
Catch Estimation and Stock Composition Spring Management Period Chinook are managed simply as upriver spring Chinook. Fisheries are non-selective and are limited by total river mouth based harvest rates. There are no in-season efforts made to separate Chinook harvest into finer level categories. CWTs are not used for fishery management. Any steelhead caught April 1 or later are counted as Skamania summer steelhead. No efforts are made to separate wild from hatchery steelhead.
Catch Estimation and Stock Composition Summer Season Fisheries Chinook are managed as Upper Columbia River Chinook. Fisheries are non-selective and are based on escapement goal management. Sockeye are managed as a single stock also. Steelhead length data are collected from any commercial gillnet fisheries, but not from the platform catch. There are no in-season efforts made to separate Chinook, sockeye, or steelhead harvest into finer level categories. CWTs are not used for fishery management.
Catch Estimation and Stock Composition Fall Season Fisheries Chinook are managed for impacts to URBs. Fisheries are non-selective and are limited by total harvest rates. Preliminary stock composition is made using skin color calls from harvest monitors. Final stock composition is made by CWTs from ticketed catch.
Catch Estimation and Stock Composition Fall Season Fisheries Current steelhead management is based on impacts to Wild B-Index steelhead ( 78 cm) harvest rates based on the Bonneville run size are used. Monitoring data on the number of unclipped steelhead 78 cm are used. TAC sometimes adjusts the unclipped number based on scale data for unclipped hatchery fish at Bonneville.
Catch Estimation and Stock Composition Fall Season Fisheries Coho are caught incidentally in fall season fisheries. There are no specific harvest limits. Total harvest of coho is made from fishery monitoring data. No efforts are made to estimate hatchery or wild impacts nor do any stock composition estimates. CWTs are not used.
Commercial Sturgeon Fisheries Most commercial sturgeon are caught in the winter gillnet fishery. Smaller proportions are landed in setline fisheries. Commercial Sturgeon landings are calculated for each pool separately from commercial fish tickets. This assumes insignificant over the bank sales which maybe an increasingly questionable assumption. There are no current funds available to monitor the winter gillnet fishery. Subsistence catch in associated with other fisheries is part of other fishery monitoring.
Commercial Sturgeon Fisheries Salmon and Steelhead catch in winter gillnet fishery. Chinook and steelhead harvest is estimated from commercial fish tickets. There may be a small number of salmon and that are taken home and not accounted for. There are no salmonid impacts in sturgeon setline fisheries.
Shad Fishery Monitoring The shad trap fishery at The Dalles Dam is monitored for salmonid bycatch. Fish tickets are used to determine the total shad harvest. Any salmon or steelhead handling mortality is included in total fishery impact limits. Shad are not directly monitored in the platform fishery.
Catch Reporting In-season catch and harvest rate estimates are reported in Fact Sheets. Post season catches are reported in Joint Staff Reports derived from TAC BA/run reconstruction tables.
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