Hatchery Origin Strays Within the John Day River Steelhead Spawning Population Chris Bare1, Ian Tattam2, and Jim Ruzycki2 1 Oregon Department of Fish and Wildlife, 305 N Canyon Blvd, Canyon City, Oregon 97820 2 Oregon Department of Fish and Wildlife, 203 Badgley Hall, EOU, La Grande, Oregon 97850 Chris Bare Ian Tattam [email protected] [email protected] 35 INTRODUCTION RESULTS r² = 0.69 30 • The John Day River supports a wild population of 350 50 summer steelhead (Oncorhynchus mykiss) with no Hatchery 25 45 hatchery supplementation and is part of the Middle 300 Wild Spawners Columbia River summer steelhead Distinct Population 20 % Hatchery 40 Segment that was listed as threatened under the Fish 250 35 Endangered Species Act in 1999 15 30 200 • The introduction of eight dams and reservoirs in the 10 lower Columbia and Snake rivers led to high juvenile 25 150 mortality rates; one mitigation strategy to increase 20 % Hatchery Origin Hatchery % 5 survival of salmonids has been mass juvenile % Hatchery transportation 100 15 Wild and and Hatchery Wild 0 10 • While the use of barges to transport smolts reduces 0 25 50 75 100 50 % Barged Hatchery Steelhead mortality associated with turbines and vulnerability to 5 predators, studies reveal the process may interfere 0 0 Figure 5. Relationship between the percentage of barged with juvenile olfactory imprinting: a process necessary '04 '05 '06 '07 '08 '09 '10 '11 '12 '13 '14 '15 '16 '17 hatchery steelhead smolts and percentage of hatchery for returning adults to home to natal streams Year origin spawners observed in the John Day River basin from 2004 to 2017. • This study investigated whether or not reduced Figure 2. Wild and hatchery fish counts and percent barging correlates with the number of hatchery hatchery origin spawners in the John Day River basin steelhead straying into the John Day River basin from 2004 through 2017. (JDR) CONCLUSIONS • Encounters with wild and hatchery adult steelhead during annual monitoring efforts has allowed us to document the long-term trends in the hatchery and natural adults returning to the basin to spawn • Since 2008, there has been a decline in the proportion of hatchery-origin spawners in the John Day River summer steelhead Major Population Group • The downward trend was preceded by declines in the Figure 3. Image of a wild steelhead ascending a proportion of Snake River hatchery steelhead smolts cascade during a spawning ground survey on Thirtymile transported through the Columbia and Snake rivers Creek. • The positive relationship between barged hatchery steelhead and straying hatchery origin spawners 35 100 suggests that reducing hatchery steelhead smolt PHOS 90 transportation in the Snake River is an effective Figure 1. Map of the John Day River basin. 30 strategy for reducing the proportion of hatchery-origin % Barged 80 spawners in the John Day River basin 25 70 METHODS Spawners 60 20 ACKNOWLEDGMENTS 50 • In addition to monitoring efforts that collect 15 We acknowledge the assistance and cooperation of the information on status, trends, and distribution of 40 private land owners that allowed us access to conduct steelhead spawning activity in the JDR, we began spawning surveys on their property, and many cooperator 10 30 documenting hatchery (adipose-clipped) strays in agency volunteers who helped us conduct the surveys. 2004 20 Funding support is provided by BPA and NOAA. % Hatchery Origin Hatchery % 5 % Barged Hatchery Steelhead 10 • We recorded the origin of adult steelhead observed during basinwide spawning ground surveys, angler 0 0 surveys, beach seining, and rotary screw trap '04 '05 '06 '07 '08 '09 '10 '11 '12 '13 '14 '15 '16 '17 monitoring in the four subbasins Spawning Year Figure 4. Proportion of hatchery origin spawners in the • To see if reduced barging of juveniles has had an John Day River basin and the percentage of hatchery effect on the percentage of hatchery origin spawners steelhead smolts transported from Lower Granite Dam straying into the John Day population, we compared (Snake River) two years prior to spawning year from the hatchery fraction to percent barged hatchery 2004 to 2017. steelhead two years prior to spawning year.