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Lower Columbia Recreational Sturgeon Fishery - 2007 Recap and 2008 Outlook and Sea Lion Impacts
| See also: | |
| Columbia/Cowlitz Smelt Fishing Reports | |
| Columbia River Forecast Archives | |
Summary of 2007 Recreational Harvest and 2008 Harvest Guidelines
The management target for the estuary fishery in 2007 was 15,274 white sturgeon not to exceed 16,274. Below Wauna an estimated 19,131 white sturgeon were caught from 50,071 angler trips which exceeded the management target. This leaves approximately 2,900 fewer white sturgeon available for the 2008 recreational fishery in the estuary. The 2008 guideline will be 13,143 fish.
In 2006, there were 3,055 sturgeon remaining on the above Wauna guideline. The balance of the unused allocation was spread over the two remaining years of the 2006-2008 Management Agreement. The revised management target for the 2007 recreational fishery above Wauna was 13,500 white sturgeon not to exceed 14,300. The total catch for the 2007 fishery above Wauna is projected to be 11,150 white sturgeon from 82,600 angler trips.
Since 2003 there has been a significant shift in the wintertime recreational sturgeon harvest from the mainstem Columbia into the Willamette River. The shift may be due to warmer (2-5 degrees C higher) water temperatures in the Willamette during January to March and generally poor smelt runs to the Columbia River over the last several years that appears to be attracting more fish (and anglers) to the Willamette during these months. Because of this increasing trend, Willamette harvest in excess of 1,530 fish caught annually during 1986-1996 was added to the above Wauna recreational fishery since 2006 to more accurately reflect the total recreational harvest in this area.
An additional 3,800 white sturgeon in excess of background levels were estimated harvested from the Willamette River bringing the combined above Wauna harvest to 14,950 fish in 2007. The 2008 recreational fishery above Wauna guideline is projected to be 13,700 fish (numbers of fish depends upon actual mainstem harvest in November and December 2007).
Population Status
Abundance of 42-inch to 60-inch fish declined from an estimated 136,900 white sturgeon in 2005 to an estimated 121,500 in 2006.
Potential 2008 Fisheries
Based on the number of fish available for harvest and concerns about a potentially declining population estimate, the Columbia River Recreational Fisheries Advisory Group generally endorsed a 4-day per week for the above Wauna fishery throughout the year and a season similar to 2007 for the estuary fishery. WDFW and ODFW staff will develop specific fishing season proposals for consideration at the December 13, 2007 Compact/Joint State Hearing.
Sea Lion Impacts
The white sturgeon population has been increasingly impacted in the past few years by predation from sea lions. This was especially significant during the winters of 2006 and 2007 when substantial numbers of broodstock-size white sturgeon were observed being killed and consumed by Stellar sea lions congregating just downstream from Bonneville Dam. Predation on smaller white sturgeon by both Stellar and California sea lions has been observed throughout the lower river. Loss of juvenile fish to predation may be impacting legal-size abundance and recruitment to fisheries. Loss of broodstock may lower population productivity and eventually reduce recruitment to fisheries.
Predation appeared to decline following initiation of hazing program in March 2006 that successfully moved the Stellar sea lions out of the area by April. Hazing was initiated again in February 2007 to deter the small group of Stellar sea lions congregating in the Beacon Rock area. Hazing for the 2007-2008 season is scheduled to begin in December 2007 and continue through February 2008.
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