Monitoring for precocious male maturation (minijacks) in hatchery programs: A case study of upper Columbia River summer Chinook salmon Don Larsen, Brian Beckman, Paul Parkins, Kathy Cooper, Deb Harstad, and Dina Spangenberg NOAA Fisheries, Northwest Fisheries Science Center Seattle, Washington
Spawning - Fall Chinook Salmon Fry Parr Age-1 Precocious parr Jack Age-2 Minijacks Age-5 Age-3 M Age-4 Sub-adults Ocean 1+ yr Spring Smolting
Variation in Age of Male Maturity Factors Affecting Age of Maturation Genetics Environment temperature food availability food quality Growth & Body energy stores Mature male salmon The Hatchery environment can significantly influence age of maturation
We ve been monitoring the physiology of Cle Elum Supplementation Hatchery Spring Chinook since implementation in 1997
On average 50% of male Cle Elum hatchery spring Chinook precociously matured at age-2 BY Release # % of males # Minijacks 1997 386,048 44% 84,931 1998 589,683 72% 211,107 1999 758,789 50% 189,697 2000 834,285 37% 153,508 2001 370,236 52% 95,520 Avg. 50% Larsen, D.A., Beckman, B.R., Cooper, K.A., Barrett, D., Johnston, M., Swanson, P., and Dickhoff, W.W. (2004). Assessment of high rates of precocious male maturation in a spring Chinook salmon supplementation hatchery program. Transactions of the American Fisheries Society. 133, 98-120.
How do we assess precocious male maturation?
Age-2 immature male chinook salmon Testes May
Age-2 precocious male chinook salmon Testes May
Plasma 11-ketotestosterone (11-KT) O OH O Major androgen in teleost fish Instrumental in the regulation of spermatogenesis
Laboratory based studies have clearly established that 11-ketotestosterone (11-KT) is significantly elevated in precocious males as much as a year prior to mating 20 15 10 * * * * *** * *** * *** * Precocious male Immature male 5 0 Dec Jan Feb Apr May Jun Sep (Campbell et al. 2004)
Every March the Cle Elum Chinook are screened for pathology just prior to volitional release Plasma collection 52% 48% Count Immature Threshold (0.8 ng/ml) Maturing 50 45 40 35 30 25 20 15 10 5 0-1.75-1.25 -.75 -.25.25.75 1.25 1.75 Log 10 11-KT (ng/ml) N = 541
Consequences of high levels of precocious maturation Ecological impacts Genetic impacts Increased straying Skewed gender ratio Loss of adult production Alter accuracy of SAR s
Entiat Hatchery Winthrop Hatchery Methow Entiat Count 50 40 30 20 10 Winthrop BY 03 23% BY 04 28% BY 05 35% BY 06 39% Leavenworth Hatchery Wenatchee 0-2.5-2 -1.5-1 -.5 0.5 1 1.5 Log 11-KT 50 Cle Elum BY 01 48% Cle Elum Hatchery Count 50 40 30 20 Entiat BY 03 13% BY 04 8% BY 05 11% Count 40 30 20 10 Count 0-1.75-1.25 -.75 -.25.25 20.75 1.25 1.75 50 40 30 Log 10 11-KT (ng/ml) 10 Leavenworth BY 03 15% BY 04 14% BY 05 33% BY 06 25% 0-1.25-1 -.75 -.5 -.25 0.25.5.75 1 1.25 Log 11-KT 10 0-2.5-2 -1.5-1 -.5 0.5 1 1.5 Log 11-KT Imnaha BY 06 51% Lostine BY 06 47%
Minijacks are ubiquitous throughout the Columbia Basin Adult return ladders are fitted with pit-tag detectors Beckman, B.R. and Larsen D.A. (2005). Up-stream migration of PIT-tagged Age 2 (minijack) Chinook salmon in the Columbia River: behavior, abundan ce, distribution, and origin. Transactions of the American Fisheries Society. 134, 1520-1541.
Minijacks were detected at Bonneville Dam from all releases 160 140 # PIT-tags detected 120 100 80 2002 2003 60 40 20 0 Carson Umatilla Clark Flat Jack Creek Easton Leavenworth Entiat Winthrop Methow Chewuch Dworshak Lostine Catherine Creek Imnaha Rapid River Knox Bridge
Mid/Upper Columbia Summer Chinook Salmon
Similkameen Pond Similkameen Carlton Pond Methow Dryden Pond Wenatchee
Methods April, 2008 collect random net grab samples of 300 fish from Carlton (Methow), Dryden (Wenatchee), and Similkameen Ponds prior to release. Measure fork length and weight, visually determined gender Collect blood and determine plasma 11-KT levels in all males via ELISA at NW Fish. Sci. Ctr., Seattle. Age-2 minijacks determined by 11-KT levels in excess of 1.5 ng/ml.
Mid-Columbia Summer Chinook - size comparison 140 3.1 120 3.7 100 4.5 Weight (g) 80 60 5.5 7.5 Fish per pound 40 11 20 22 0 240 Carlton Pond Dryden Pond Similkameen Pond 0 220 Length (mm) 200 180 160 140 120 100 80 Carlton Pond Dryden Pond Similkameen Pond
11-KT frequency distribution between stocks Carlton Pond Count 30 25 20 15 10 5 0-1.5-1 -.5 0.5 1 1.5 37% of males Minijacks 74, 000 fish (400,000 released) 30 25 Dryden Pond Count 20 15 10 5 0-1.5-1 -.5 0.5 1 1.5 30 17% of males Minijacks 73,440 fish (864,000 released) Similkameen Pond Count 25 20 15 10 5 0-1.5-1 -.5 0.5 1 1.5 Log 11-KT 10% of males Minijacks 28, 800 fish (576,000 released)
11-KT levels in males and minijacks 18 16 14 11Ketotestosterone (ng/ml) 12 10 8 6 4 2 Male Minijack 0-2 Carlton Pond Dryden Pond Similkameen Pond
Minijacks are generally the largest fish 240 220 200 Length,mm 180 160 Female Male Minijack 140 120 100 80 Carlton Pond Dryden Pond Similkameen Pond
Minijack rates may influence SAR s (avg. % over 11-13 years).9.8 Similkameen.7 SAR (%).6.5.4 Dryden Carlton.3.2 R 2 = 0.82.1 5 10 15 20 25 30 35 40 Minijacks (% males) Columbia Basin Research School of Aquatic and Fishery Science University of Washington Web@cbr.washington.edu http://www.cbr.washington.edu/trends/index.
Conclusions Minijacks are ubiquitous among all spring Chinook populations we ve surveyed. Supplementation programs using localized broodstocks may have increased susceptible to this life-history. Minijack rates among hatchery Summer Chinook populations are relatively variable (high and low). The economic, ecological, and genetic impacts of this phenomenon may be significant Smolt quality monitoring is a useful tool for helping make informed decisions about hatchery uses and practices.
Acknowledgments Cle Elum Hatchery- Charles Strom and staff WDFW-Todd Pearsons and staff, Steve Schroder, Craig Busack Yakama Nation Fisheries-Dave Fast, Mark Johnston, Bill Bosch Leavenworth Hatchery Complex Facilities-Steve Croci, Dan Davies, Al Jensen, Chris Pasley, Craig Eaton, Jason Reeves Nez Perce Tribe - Peter Cleary, Jim Harbeck ODFW- Tim Hofnagle, Diane Deal and staff (Lookingglass Hatchery), Sam Onjukka and staff (ODFW fish health) WDFW Upper Columbia - John Penny and staff (Dryden), Guy Wiest, Dave Dinsmore (Carlton), Tim Holder, Carol Coleman(Similkameen) Chelan and Grant County PUD s - Chuck Peven and Russ Langshaw USFWS Pathology Lab, Olympia, WA.- Ray Brunson, Joy Evered, Sonia Mumford, Chris Paterson Bonneville Power Administration - Deborah Docherty, NOAA Biop Funding