Kokanee Captive Broodstock at Spokane Hatchery

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1 Kokanee Captive Broodstock at Spokane Hatchery Guy Campbell and Steve Roberts Washington Department Fish & Wildlife

2 What is a Kokanee? Kokanee (Oncorhynchus nerka ) is a land locked sockeye salmon that spends their entire lives in freshwater Native to British Columbia, Alaska, Washington, Idaho, Russia and Japan

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4 Why the Captive Brood Program? Lake Whatcom kokanee eggs will no longer have pathogen-free status. Currently, this stock supplies nearly two-thirds of Washington state s kokanee. Solutions Development of a captive broodstock Development of new lake based broodstocks

5 Kokanee Sources for Captive Brood 2004 Brood year - Lake Whatcom stock 2005 Brood year - *Sullivan Lake stock 2006 Brood year - *Sullivan Lake stock *Originated from Lake Whatcom stock

6 About Sullivan Lake Stock The 1,380 acre lake is located in the northeastern part of Washington State about 4 miles southeast of Metaline Falls The lake is 3.6 miles long and averages 0.6 miles in width

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8 Spokane Hatchery Water Source Griffith Spring from the Spokane Aquifer produces 9,000,000 gallons per day of pathogen free water

9 Incubation Water Temperature Kokanee eggs are incubated after fertilization in chilled 41 F water until right before hatching. The remainder of egg development occurs in 51 F water.

10 Incubation Techniques Eggs are incubated and hatched in wire baskets in shallow troughs Shallow troughs are set at 8 gpm of flow Eggs are treated daily with a 1:600 formalin treatment to prevent fungus

11 Outdoor Rearing Parameters Spring water supplies constant 51 F Raceways - 9 x 6 x 2.5 = 1,350 ft^3 Water flow gpm Flow indexes below 1.65 Density indexes below 0.3

12 Monitoring Fish Growth It has been observed in other kokanee captive broodstocks trials that male kokanee tend to mature as two year olds if they are allowed to grow to fast. We tried to minimize this by strictly adhering to our predetermined target sizes.

13 Target Sizes Established Target Sizes - 36 fpp as one year olds fpp as two year olds fpp as three year old spawners To ensure establish target sizes are being followed. Fish growth is closely monitored using a fish projection program.

14 Actual Growth Observed Captive Brood Kokanee Growth Goal Fish per Pound Age Class

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16 Diets Used It was determined to use a good high quality diet Brdyr- (Skretting s Clark Fry/Vitalis diets) 2005 Brdyr- (Skretting s Clark Fry and Ewos Transfer/Brood diets) 2006 Brdyr- (Skretting (Clarks Fry and Ewos Transfer/Brood diets)

17 Spawning Procedures Only three-year old adults used Spawning is performed at a 1:1 ratio (male to female) Eggs are manually stripped into a spawning pan Milt and saline solution are then added with the eggs for fertilization Eggs are then water hardened for one hour in iodine-water solution

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20 Spawning Results in Brood year Oct 16 thru Nov 27, 2007 A total of 888 females were spawned yielding 503,000 eggs A fecundity of 566 eggs per female 6.6% egg mortality from fertilization to eyed-stage

21 Disposition of 2004 Brood year 3% 12% 19% Jack- 2 year old Male Spawners Female Spawners Unspawned Mortality 33% 33%

22 Spawning Results in Brood year Oct 22 through current 560 females yielding 326,000 green eggs An egg fecundity 582 eggs per female Egg mortality to eyed-stage appears to similar to 2004 brood

23 Problems Encountered 2004 Brood -Males maturing as two year olds -Three year old adult mortality from crinkle back the absolute cause is still unknown Brood -Males again maturing as two year olds -Three year old adult mortality from crinkle back still evident but total adult mortality reduced from 12% to 8%.

24 Summary In general, the captive brood kokanee program at Spokane Hatchery has had success. Expanding this program is a viable and practical option to reduce the impacts statewide of losing the Lake Whatcom kokanee egg source.

25 Acknowledgements Spokane Complex Manager- Rich Watson Staff at Spokane Hatchery- Mike Holm Jeff Lombard Jim Muse