Steelhead mortality from gillnetting may be lower than thought

New data indicates that gillnetting may not be as harmful to steelhead as previously thought.

The ability of commercial gillnetters to fish the mainstem Columbia River has mostly been removed by harvest reforms in Oregon and Washington, citing gillnetting as non-selective and potentially damaging to salmon and steelhead, including the 13 species listed as threatened or endangered under the federal Endangered Species Act.

Gillnet fishing continues, but almost all allowed gillnetting is in designated off-channel or select fishing areas where the gillnetters can target hatchery-produced salmon.

Even in those areas, gillnetters still catch steelhead, including wild steelhead, and previously it was thought that nearly half of the steelhead returned to the river after being snagged in a gillnet would die. In fact, historically biologists and policymakers have thought the mortality rate to be 49 percent.

That estimate could be cut in half if recent preliminary data is confirmed over the next several months.

According to new and not yet fully reviewed data from the Oregon Department of Fish and Wildlife, the mortality rate for steelhead returned to the river after being tangled in a gillnet could be as low as 8 percent to 24 percent.

The data is from an “amalgamation of recent observations of the commercial fishery” from the years 2009, 2012 and 2017, said Tucker Jones, ocean and salmon Columbia River program manager for ODFW. The conclusions are preliminary, he said.

He added that the prior rate was based on observations of the commercial fishery from 1988 to 1990, but the “recent observations actually have a substantially larger combined sample size than the older data set.”

“Pending some independent review, our analysis looks like we might have well overestimated the mortality,” Bill Tweit, special assistant to the director for the Washington Department of Fish and Wildlife, said in a January 22 Daily Astorian article.

Both Tweit and Jones will present the information to their respective Fish and Wildlife commissions in the coming months.

“Right now the rates have not yet been fully reviewed and until that happens they are only preliminary,” Jones said. “I hope to present the results of the observations at the March Commission meeting, but even those are still likely to be preliminary.” The meeting is March 16 in Salem.

Oregon Senate Bill 830, passed in 2012, called for the removal of all commercial gillnets from the mainstem Columbia River downstream of Bonneville Dam by December 31, 2016.

Adopted by both the Washington and Oregon commissions in 2013, the initial harvest reform policy was designed to promote conservation of salmon and steelhead, prioritize recreational salmon fishing in the lower Columbia River, and over a four year transition period move gillnet fisheries into off-channel or select areas by Dec. 31, 2016.

The states also were to provide additional hatchery releases in select areas, while expanding commercial fishing opportunities through the use of alternative fishing gear. Oregon has experimented with beach and purse seines with varying degrees of success, while in Washington pound nets, also known as fish traps, are going through tests near Cathlamet by the Wild Fish Conservancy.

Along with these changes, including moving to off-channel areas where they can target hatchery fish, gillnetters are also using nets with varying mesh sizes, fishing for shorter periods and often at night, all depending on what they are fishing for and what type of fish is in the river.

Jones said ODFW hasn’t “yet really dug into why things are different now (with the mortality rates). There have been a number of changes in both how the fisheries are managed and how the fishers fish, but to try to guess which (or any) of those things are in play would be pure speculation.”

The two-state Columbia River Compact met Tuesday to discuss coming fishing seasons, including opening select areas to gillnetting for the 2018 fishing season.