Tuesday, July 31, 2012

Hatchery Supplementation Decreases Genetic Diversity in Salmon Populations

Over the last several years, a string of science papers have come out of more than a decade of research that was done on the Hood River prior to the removal of Powerdale Dam. By sampling every fish passed through the fish ladder to spawning areas above the dam for multiple generations researchers were able to track the reproductive success of individual fish, comparing the number of adult offspring produced by both wild and hatchery fish. 

The work has served to strengthen the argument against the use of hatcheries in restoring wild populations and provided compelling evidence that wild broodstock hatcheries are not a viable solution to the problems associated with hatchery programs. Among the papers that have come out of the research on the Hood are several publications that have demonstrated the rapid decline in fitness that results from domestication of steelhead in a hatchery environment. Now Mark Christie, a researcher at Oregon State University and a group of colleagues have published another piece of their work which examines the impact of the wild broodstock hatchery program on effective population size, a metric that reflects the effective number of fish that contribute to the next generation. Effective population size is a good predictor of the ability of a population to maintain crucial genetic diversity. 

They found that despite the fact that the total number of spawners was enhanced by the presence of hatchery fish, hatchery supplementation actually served to decrease the genetic diversity of the wild population. This is critical information for managers who may be temped to resort to using hatcheries as a means of increasing the size of spawning populations over the short term. 

Monday, July 30, 2012

Mark Selective Fisheries are an Essential Tool for Conservation

A neat write up in the most recent issue of the Columbia Basin Bulletin summarizes a recent publication on mark selective fisheries with a particular focus on the differences in hatchery management between California, Oregon and  Washington. Unlike Oregon and Washington, the vast majority of hatchery chinook that are released in California are not marked with an adipose fin clip. While there are significant commercial and sport fisheries for Chinook in California, an inability to distinguish between hatchery and wild fish remains a challenge in managing harvest and limiting impacts on wild populations. More than 35 million juvenile hatchery Chinook are released each year in the Sacramento River system, and hatchery fish make up almost 90% of returning adults. 

More information in the Columbia Basin Bulletin:

Sunday, July 22, 2012

Away In the Field...In the Meantime

photo courtesy of Yakama Nation Fisheres


Apologies for the dearth of updates of late. In case you were wondering, the Osprey does continue exist and while we look forward to continuing to provide timely news on wild fish science, policy and conservation we're away in the field until the end of the month. In the meantime enjoy this photo of a steelhead leaping at BZ Falls on the White Salmon. The river had been blocked for a century by Condit Dam which came down last fall.

While we're away, please check out the Wild Steelhead Coalition website
The Wild Fish Conservancy
and The Native Fish Society

Sunday, July 8, 2012

Damnation Trailer Released

The makers of Damnation, a film which tracks the growing momentum behind dam removal and some of the ecological and cultural context around the issue, have released a trailer for the film which is set to be out in the Fall of 2013. If the trailer is any indication, the film which is supported in part by Patagonia, should be a well made and visually stunning documentary. Check out the trailer with footage from Marmot Dam, Elwha and Glines Canyon Dam, Condit and many of the Snake and Columbia River dams.

Friday, July 6, 2012

Steelhead Spawning above Elwha Dam

A cool piece from the Seattle Times on wild steelhead spawning above Elwha Dam. With the Lower Elwha turbid and largely unsuitable for spawning in the near term biologists have been capturing fish that are congregating at the clear water outlet of the hatchery, tagging them and transporting them to the Little River. Some fish have apparently also found their way to the Little River and Indian Creek without the help of the recovery team. Check out the article from the times which also includes some very cool photos from biologist John McMillan.


Removal of Glines Canyon is proceeding faster than expected and the dam should be gone by next summer. The dam which once stood 210 feet has been cut nearly in half already with much more predicted to be gone by the end of this month when crews will be conducting a series of controlled blasts. Track the progress on the Elwha River webcam.


Wednesday, July 4, 2012

Okanagan Sockeye Thriving Without Hatcheries

In a summer of banner sockeye returns, the Okanagan River which straddles the US-Canadian border in North Central Washington is expected to see record returns of more than 400,000 sockeye. Sockeye returning to the Okanagan migrate more than 500 miles from the ocean, passing 9 mainstem Columbia River dams on the way to their spawning grounds.

The Okanagan run is also unique in another way, there is no hatchery production in the Okanagan basin. Instead co-managers with the Colville Nation and WDFW have focused on habitat improvements. This work, coupled with court mandated flow improvements in the Columbia and favorable ocean conditions have led to dramatic increases in the productivity and abundance of Sockeye in the Okanagan and should provide a template for other recovery efforts in the Columbia system where millions of dollars are spent each year funding hatchery programs that ultimately undermine the productivity of listed wild stocks in the basin. 

More information in the Bellingham Herald: