Commercial fishers in next year's Columbia River hatchery spring chinook fishery will be required to use tangle nets with mesh no larger than four-and-a-quarter inches to protect steelhead and wild chinook salmon.
That mesh size limit was set by the Columbia River Compact in a meeting today in Portland. The compact, composed of Oregon and Washington fishery managers, determines commercial fishing regulations for the river.
The new restriction on tangle net mesh size applies to non-treaty commercial fishers in the 2003 Columbia River spring chinook fishery. The exact dates of that season, along with other rules for the fishery, will be set at the compact's January meeting.
The new mesh size limit is aimed at reducing steelhead encounters, which were unexpectedly high in this year's experimental spring chinook tangle net fishery. Tangle net mesh sizes of up to five-and-a-half inches were allowed in the spring 2002 fishery. Tangle nets reduce mortality on non-targeted species by entangling fish rather than trapping them by the gills like traditional gill nets.
However, the five-and-a-half-inch tangle nets gilled or body-clamped up to 80 percent of steelhead encountered, while four-and-a-quarter-inch nets are estimated to gill or clamp only 4 percent of steelhead caught, according to an analysis by Washington Department of Fish and Wildlife (WDFW) staff. Mortality rates are higher among fish that are released after being compressed in net mesh.
Mesh size is defined as the length from knot to knot when the net is tightly stretched.
"Besides restricting net mesh size, the department will also aggressively enforce 45-minute net soak time limits and recovery box use requirements," said Larry Peck, WDFW deputy director.
On-board recovery boxes are used before non-target fish are released back into the water, in order to boost their chances of survival.
Commercial Selective Fishing in Washington