Toledo Creek Could Play Big Part in Increased Salmon Harvest

Oregon Department of Fish and Wildlife biologist Chris Lorion prepares to release a wild Mill Creek salmon after measuring its size and taking scale samples. (Photo by Larry Coonrod)

By Larry Coonrod of the News-Times

TOLEDO--In a shift more than a decade in the making, a small east Lincoln County stream is slated to play a key role in setting the 2013 coho sport salmon season. 

Last month the Pacific Fishery Management Council approved the use of jack coho counts in Mill Creek - a tributary to the Yaquina River - as a predictive indicator of the following year's adult salmon return. The policy could potentially increase the number of coho salmon allocated to anglers. 

Coho jacks are immature 2-year-old salmon that return to their home streams a year ahead of adult fish. A high jack count is a good gauge to the number of mature 3-year-olds that will return to spawn the following year. 
 Amendment 13 to the PFMC Salmon Management Plan, adopted in 1999 and revised in 2000, uses jack coho counts from the Columbia River along with marine survival predictions to establish allowable harvest.
  
"If you look at this relationship, hatchery coho versus the measure of wild smolt survival, the correlation is very weak, almost non-existent ," said Bob Buckman, Oregon Department of Fish and Wildlife district biologist in Newport. "So our forecast method does not work. That's not surprising given we're using Columbia River hatchery coho to forecast coastal wild coho as far south as the Coquille River." 

At one time, the state annually released 5 million hatchery raised coho smolts into coastal streams. But starting in the mid-1990s, it began reducing that number as part of an effort to rebuild wild salmon populations. Today, ODFW plants just 260,000 coastal coho smolts a year, spread between the Nehalem, Trask and Umpqua rivers.
Buckman said biologists knew Columbia River counts were not a good indicator of wild coastal runs, so ODFW set up seven life cycle monitoring sites in coastal streams to count the outgoing smolts and returning adults. Three sites are in Lincoln County: Cascade Creek in the Alsea basin, Mill Creek, in the Siletz Basin and Mill Creek in the Yaquina River, which also supplies drinking water for Toledo. 

Toledo's Mill Creek provides the most accurate jack count of the seven monitoring sites.

 "It's real hard to capture jacks consistently because you need tight bar spacing, and when you get tight bar spacing, in October and November you catch every alder leaf coming down the river," Buckman said. 

Biologist Chris Lorion said Mill Creek Reservoir creates an impassable fish barrier that forces salmon into a fish ladder, and the leaves sink in the lake before reaching the water outlet - factors that allow the close bar spacing needed to capture jacks, which can run as small as 14 inches. 

 "We can count 100 percent of the jacks and adult salmon spawning above the reservoir," he said. "In a low year, we'll get about 250 coho, and in a good year, we've seen 1,300 fish." 

Lorion and fellow biologist Hope Rieden empty the traps at the three central coast sites almost daily during the fall, measuring each female fish before releasing them to continue their spawning run. 

"There is a correlation between the size of a female and the number of eggs she lays, so we can get an idea of how many smolts we should see," Lorion said. 

 In the early spring, ODFW is able to trap and count a high percentage of coho smolts spawned upstream of Mill Creek Reservoir. Comparing smolts to returning jacks tell biologists how well each year's spawn survived in the ocean.  A decade's worth of data show Mill Creek a far better indicator of coastal coho returns than the Columbia hatchery jack counts.

"If we look back at what has happened in the last 12 years, Mill Creek does a better job of identifying high years, for Oregon coast coho," Buckman said. "Mill Creek also does a better job of identifying low years. That's why there was a strong argument to adopt it." 

While Mill Creek data may provide a higher catch quota for anglers in good years, it could lead to lower catch numbers in the bad years. 

"If you look at the three highest years, the old method gave us a 15-percent harvest impact, the new method would have gave us 28 percent," Buckman said. "In low years, the old method had us hitting 12 percent, whereas the new method would be 10 percent. So it does a better job on both the lows and highs." 

The Pacific Fishery Management Council approved the use of Mill Creek data for one year and plans to use the information in setting 2013 quotas. Buckman said PMFC is unlikely to go back to the Columbia hatchery jack return method. 


"There will be some ability to have improvement in wild coho harvest, but this isn't just a scheme to get more harvest," Buckman said. "It prevents over-harvesting in the bad year. It will still be very conservative management."
   
Even with the more accurate survival predictions from Mill Creek and improving numbers of central coast coho in recent years, a commercial coho season is unlikely to occur anytime soon. Recovery of wild coho from southern Oregon and northern California streams, as well as the Columbia River, remain a concern.

"Those fish are mixed in the ocean with the much more abundant Oregon coastal wild coho," Buckman said. "They are much less tolerant to harvest and that will continue to constrain the ocean fishery."

 Contact Assistant Editor Larry Coonrod at 541-265-8571 ext. 211 or email larry@newportnewstimes .com.