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NWPPC Recommends Funding for 2003 Tangle Net Fishery by Barry Espenson Columbia Basin Bulletin - December 20, 2002

The Northwest Power Planning Council on Thursday moved an experimental lower Columbia River selective spring chinook harvest proposal to the front of the funding line so the project can be implemented in February.

Funding consideration for the commercial "tangle net" evaluation was to take place along with the 104 projects submitted through the Council's systemwide/mainstem project selection process. But funding recommendations are not due in the process until April, so sponsors asked early consideration. The research and monitoring effort is sponsored by the Oregon and Washington departments of fish and wildlife and the University of Idaho.

The Council recommended that two of the project's original five research objectives be funded. The compromise funding amount was $633,000 instead of the originally requested $1.3 million. The Council recommendation now goes to the Bonneville Power Administration for final funding approval and contracting.

The plan is to implement, for the second year in a row, a full fleet fishery in which smaller size mesh nets are deployed to harvest spring chinook. The so-called "tangle nets" are similar to gill nets but the smaller mesh better allows the live capture, and release, of selected fish. The gill nets, as the name implies, snare the fish by its head or gills, in many cases suffocating the fish. The smaller mesh tangle nets don't allow the big spring chinook to push as far through the net, entangling them often instead by the teeth.

The tangle net experiment is intended to determine if the nets are an effective live capture technique. Live capture allows the commercial fishers to survey the fish for fin clips or other hatchery markings and then release unmarked, and presumably wild, fish. Several wild Columbia basin spring chinook stocks are listed under the endangered species act. Another study goal is to allow the commercial harvest of prized spring chinook hatchery fish with minimal impact on listed wild stocks.

In a limited experiment in 2001 that employed 20 vessels, researchers found that the tangle nets were effective at capturing the spring chinook while allowing more than 95 percent of the unmarked fish to be released unharmed.

A full fleet test of 4 ½- and 5 ½-inch tangle nets in 2002 found that "tangle nets were effective at capturing spring chinook and that unmarked spring chinook were released in good condition.," according to a NWPPC memo. But the "bycatch of steelhead far exceeded the sponsors expectation" and raised the ire of fish conservation groups such as Oregon Trout, Washington Trout and the Native Fish Society.

Steelhead are designated as a sport fish and thus are ineligible for commercial sale by non-tribal fishers. Numerous Columbia Basin steelhead stocks are also listed under the ESA.

But despite the fact that the steelhead must be released, the groups were concerned about the short and long-term impacts of the sport fish being caught up in the nets. The larger of the net sizes used in 2002 seemed to serve as more of a gill net for the steelhead, which are on average much smaller than the chinook.

The 2002 fishery resulted in 14,200 marked spring chinook being taken. In addition, 21,700 wild and hatchery steelhead were also "encountered. The research indicates that immediate mortality of the released steelhead was 2 percent and 84 percent of the steelhead were released in "excellent condition.

The states of Oregon and Washington, which regulate Columbia mainstem fishery, opted to limit commercial fishers to 4 1/4-inch nets during a planned continuation of the tangle net experiment in 2003. The smaller mesh is expected to reduce the capture and physical impact to steelhead. The WDFW's Bill Tweit said the timing and placement of the late winter/spring commercial fisheries will also be manipulated to avoid steelhead "encounters."

A letter to the Council from the project sponsors said that some of the suggestions made by the fish groups will be applied as the research and fishery monitoring is carried out.

The Council memo said that the project sponsors seemed to have addressed the concerns of the Independent Scientific Review Panel and of Oregon and Washington Trout and the Native Fish Society. The funding approval comes with the condition that the sponsors provide real-time data related to the commercial catch, bycatch and survival study data "so that it can be provided to these and any other interested parties."

Council Chairman Larry Cassidy of Washington praised the sponsors and NWPPC and Bonneville Power Administration staff for "yeoman's work" in fine tuning the proposal so that it was acceptable. BPA funds the Council's fish and wildlife program.

"This will give us an idea if those steelhead can be avoided" while still providing a valuable chinook fishery, Cassidy said.

"This is really important to everyone," Cassidy said.

The project was ultimately recommended for funding at a level similar to 2002, which was $632,698. The project will focus on two primary tasks:

NWPPC Recommends Funding for 2003 Tangle Net Fishery
• evaluating long-term survival of steelhead and spring chinook salmon following capture in tangle nets, and
• determining the feasibility of using refined live capture selective fishing methods and gear in a full fleet. This task involves monitoring the fishery for ESA-impacts, capture condition profiles, recapture frequencies, and immediate mortality rates of spring chinook and steelhead.

The Council on Dec. 11 received a letter from NOAA Fisheries confirming its support for the select harvest gear evaluation. The federal agency is charged with protecting listed salmon and steelhead. Its 2000 biological opinion on hydrosystem operations calls for a number of "off-site" measures that can be carried out to improve survival of listed species. The development of selective harvest strategies are among those measures.