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Mark Freeman's Commentary Rogue anglers could be in store for a frustrating season Rogue River salmon anglers must accept saving fish over catching them this summer under planned water flows meant to spare as much of the spring chinook run from death by disease as possible. With drought conditions making a deadly columnaris outbreak virtually inevitable, state biologists have drafted a water-release strategy for Lost Creek Lake that aims at delaying the warm-water pestilence as late into the run as they can. By raising and lowering dam water releases almost daily, biologists hope to use only as much water as necessary to draw migrating chinook safely through the warm waters of the lower Rogue Canyon in May and most of June. Juggling these releases will spend the lake�s water reserves more frugally than simply setting Rogue flows at a safely high rate until the water stored for fish is gone. "Fluctuating the flows gives us the best chance of getting these fish upstream with the amount of water we have available," says Mike Evenson, an Oregon Department of Fish and Wildlife biologist who helped write the department�s waterflow strategies. "The longer we can delay a columnaris outbreak," Evenson says, "the better." But this strategy could make the spring fishing season a very frustrating one for upper Rogue salmon anglers. The fluctuating flows are expected to make the chinook � already known to be finicky fish � even less apt to bite than normal. Historically, chinook will first adjust to changes in water levels before biting baits and lures again, and regular changes in Lost Creek dam flows could mean lean catches during May and June. "But we really don�t have much choice here," Evenson says. "If you don�t get the fish upstream, you don�t have a fishery." Putting fish needs ahead of fishing makes anglers such as Kern Grieve, one of the patriarchs of the region�s guiding industry, support the ODFW�s efforts this year. "If they�re going to work on it in that direction, then I�m all for them," Grieve says. "This is the right thing to do. "If it�s something that�s needed," Grieve says, "then nobody will argue with them." Columnaris is a virus that blooms naturally during warm and low river flows of drought years. It suffocates chinook salmon � but not people or other mammals � by attacking the fish�s gills. Columnaris hits chinook the hardest of all Rogue fish, with the river�s spring run less resilient to it than the fall chinook. Columnaris usually breaks out when river temperatures eclipse 68 degrees, but not always. When it does, it spreads like a plague through the water, leaving thousands of dead fish in its wake. That�s what occurred in 1992 and again in �94, when two of every three adult spring chinook died. The �92 die-off was so bad it forced a mid-season closure of spring chinook fishing on the Rogue to protect wild fish. The best tonic for staving off these outbreaks is higher, cooler river flows. But getting them during a drought year means an unusually high reliance on water stored in reservoirs that also are low in drought years. Once an outbreak starts, it�s virtually impossible to reverse. On poor water years like this one, it means that biologists must do everything they can to delay the die-offs in the canyon. Therefore, the trick is to get as many chinook through the canyon alive and into the cool upper Rogue before the plague arrives. Using river-flow data for the Rogue Canyon area and predicted air temperatures during the summer months, the ODFW has crafted a computer model that can predict how much water is needed through the canyon daily. For instance, if air temperatures are predicted at 70 degrees in Medford, then a flow of 2,500 cubic feet per second is needed at Marial, about halfway through the canyon stretch. Hydrologists will first estimate how much water is flowing into the Rogue from tributaries, then adjust the Lost Creek Lake releases accordingly. The trick is to get the predictions right, because it takes two days for the lake water to reach the canyon. For an 80-degree day, the target canyon flows are 3,500 cfs, and 4,500 cfs if the air in Medford hits 90 degrees. Whatever the target canyon flows are, the dam releases will be capped in the 3,000 to 3,500 cfs range for safety reasons. The ODFW has targeted 1,000 acre-feet of Lost Creek Lake water to save the spring chinook, and that water is expected to be gone by the end of June. Barring a Siberian spring here, this scenario likely will lead to a 10 to 30 percent loss in the spring chinook run this year, says Tom Satterthwaite, an ODFW fisheries scientist. The agency also has 78,000 acre-feet of stored Lost Creek Lake water to minimize the loss of fall chinook from columnaris in August and September. The ODFW will use its traditional August spike of water to draw the fall chinook upstream, but Satterthwaite still expects a 25 to 75 percent loss in the fall chinook run. While saving chinook is the top priority for summer water strategies, saving the spring chinook is tantamount, Satterthwaite says. The wild spring chinook are depressed; the fall chinook run is far more vibrant and more apt to withstand a massive die-off. "I�d rather see them work on saving the springers, and we�ll all keep our fingers crossed on the fall chinook," Grieve says. (Staff writer Mark Freeman covers the outdoors for the Mail Tribune. Call him at 776-4470, or e-mail him at: [email protected] ) Mail Tribune Home | Ottaway Newspapers, Inc. | Dow Jones & Co., Inc. | Privacy | Contact Us Copyright � 2001 Mail Tribune, Inc.