After a three-year moratorium on keeping white sturgeon caught between the mouth of the Columbia and Bonneville Dam, a modest retention season started this week. By the time last weekend arrived, fishermen had found where the sturgeon were gathered within the vast Columbia estuary and catches were good. Local anglers are happy to see some progress toward a return to normal for this important fishery.
Columbia white sturgeon venture out into the nearby ocean and even into Willapa Bay, but are formally considered a fresh-water fish — the largest in North America. They can live more than a century and have become legendary among fishermen for their strength and size, with old sturgeon sometimes weighing hundreds of pounds. The much younger and smaller ones that anglers are permitted to keep — only 44 to 50 inches from snout to the fork in the tail — are locally renowned as one of the most delicious fish.
Like many other species, white sturgeon are struggling with habitat loss and deteriorating environmental conditions. During the drought year of 2015 for example, 80 breeding-age sturgeon died in the vicinity of Bonneville — possibly victims of too-warm water or perhaps harmful changes in water oxygen levels. Stellar sea lions also have multiplied and found their way into sturgeon holes, exerting considerable hunting pressure. Fleeing predators disrupts the sturgeons’ breeding patterns.
There also is little doubt that human fishing pressures played a role in sturgeon declines that led to the 2014 moratorium. When salmon numbers plunged in the 1990s, private and charter fishing heavily switched to sturgeon with an enthusiasm it was easy to foresee would lead to trouble.
We now are in the rebound period. Fortunately, state conservation measure appear to be succeeding, with an estimated 165,600 legal-size sturgeon in the river below Bonneville, up from 147,000 last year and 72,700 in 2012. Fishery managers have set an extremely conservative 3,000-sturgeon catch limit in the ongoing season — disappointing but much better than no season at all. The middling-sized sturgeon fishermen are allowed to keep generate a lot of economic activity for Columbia estuary ports, merchants and charter operations.
A study funded by the Bonneville Power Administration starting in 2000 has found female sturgeon do not sexually mature until they’re at least 18 to 32 years old and only spawn about once every three years. Although not ideal fishing conditions, biologists have learned spawning success is best during high-flow years when the river creates turbulence over rough substrate or rocky-river bottoms — so this winter’s intense rain and deep mountain snows may have a silver lining in future years in terms of producing young sturgeon.
Conservation and next steps
Sturgeon are in trouble worldwide and caution is obviously warranted when it comes to harvest and stress. In this gloomy picture, the Columbia actually is something of a bright spot, with a 2015 estimate of up to 1 million white sturgeon of all ages from Bonneville to the river’s mouth. It is especially important to protect breeding fish age 18-plus — they are vital to the species’ future. “It’s a resource that’s not replaceable,” a scientist observed in 2015. “Those big spawners, we know how valuable they really are.”
Continuing proactive management of sea lion populations is clearly justified. Although the idea is repellent to avid animal-right activists, their numbers are out of proportion to available prey in the Columbia River as it exists today. Responsible wildlife management means adjusting sea lion numbers to match their niche in what is now an inherently human-centric environment.
Sturgeon are well suited to hatchery propagation. The states should begin such a program.
Fishery managers are being careful about sturgeon. This is understandable, even if disappointing. But they must begin being more bold in enacting long-term plans for viability of these ancient and treasured fish.