Strategies to Maximize the Efficiency of Using Parentage-based Tagging as a Tool to Meet Management and Research Objectives By Carl Stiefel Idaho Department of Fish and Game

Idaho’s Hatchery Steelhead Programs 5 Hatcheries Annually Release – 7.6 m hatchery smolts – Of which, 1.9 m (25%) are coded-wired tagged (CWT) Salmon River Clearwater River SnakeRiver

Anderson and Garza (2005) Annual sampling and genotyping of broodstock Parental genotype database Assign the progeny to parents Essentially all fish are genetically tagged Pilot Study (Steele et al. IDFG Report ) – 100 % assignment accuracy – 97.3% assignment rate Parentage-based tagging (PBT) or

Advantages of PBT Noninvasive tag No tag loss No tag induced effects Near complete representation of production Nonlethal sampling Extremely high resolution, identify parents!!! Brood Year Hatchery Rearing information Why use PBT?

Can PBT be applied at a mass production scale and still meet management and research needs? Depends on Ability to track family units through culture phase of life cycle. Level of interest. – Large scale To brood year, hatchery, and stock. – Adult accounting – Moderate scale To release group. – Fishery management – Straying – Fine scale To experimental group. – Heritability of Age at Maturity – Manipulative Rearing Experiments

Facility/program characteristics that facilitate tracking of family units to release group Every hatchery will require a unique PBT Plan/Model. Lumping family units is good. Splitting family units may cause complications if not managed. Release goals set in intervals of the largest group of intact family units.

Best case scenario lumping to the release Vat-A Vat- B Raceway-A Release Group A Release Group B

Vat-A Vat- B Raceway-A Release Group A Release Group B Largest group of intact family units Best case scenario lumping to the release

Worst case scenario lumping and splitting Vat-A Vat- B Raceway-D Raceway-E Raceway-F Vat-C Raceway-G Raceway-H Raceway-I Release Group A Release Group B Release Group C Egg Trays Raceway-A Raceway-B Raceway-C Release Group D

Maximized PBT Scenario Vat-A Vat- B Raceway-D Raceway-E Raceway-F Vat-C Raceway-G Raceway-H Raceway-I Release Group A Release Group B Release Group C Egg Trays Raceway-A Raceway-B Raceway-C Release group size are in intervals of your largest group of intact family units.

Vat-A Vat- B Raceway-D Raceway-E Raceway-F Vat-C Release Group A Release Group B Raceway-G Raceway-H Raceway-I Raceway-A Raceway-B Raceway-C M&E activities do not have to dictate release goals!!!! Egg Trays Alternative scenario lumping and managed splitting

Vat-A Vat- B Raceway-D Raceway-E Raceway-F Vat-C Release Group A Release Group B Raceway-G Raceway-H Raceway-I Raceway-A Raceway-B Raceway-C M&E activities do not have to dictate release goals!!!! Egg Trays X

Vat-A Vat- B Raceway-D Raceway-E Raceway-F Vat-C Release Group A Release Group B Raceway-G Raceway-H Raceway-I Raceway-A Raceway-B Raceway-C M&E activities do not have to dictate release goals!!!! Egg Trays X 75% PBT Tagging Rate 60% PBT Tagging Rate Alternative scenario lumping and managed splitting

Approaches to tracking family units to release group – Set release group size in intervals of the largest group of intact family units. – When not possible due to logistics or management needs. Limit the number of split family units. – Apply a “PBT tagging rate”. Pool multiple release groups into a single release group.

Considerations for hatcheries regarding PBT More detail oriented than “standard production” – Minimize or eliminate “topping off” to meet production goals – Develop egg request for each release group Maintaining intact family units during – Egg enumeration – Marking Catastrophic events may impact ability to track family units – This has happened and has been managed effectively Coordination of information essential – Tracking family groups – Relating release information to recovered samples

Sounds like a logistic nightmare? Not really – Initial PBT plan development Requires a lot of work and coordination Unique for each facility – Subsequent PBT plan refinement/modification Is much easier

Proposed PBT Tagging Rate Brood Year 2012 Of the 7.6 m steelhead to be released. Approximately 6.8 m (90%) will be PBT tagged to release group. – The remaining 10% will be PBT tagged to hatchery. 24 out of 28 release groups have a PBT tagging rate of at least 80%.

By tracking family units to release group you can… Assess contribution to run. Evaluate contribution to fisheries. Evaluate hatchery straying into natural production areas. Conduct other research – Manipulative Rearing Experiments

Conclusions M&E and hatchery staff need to work closely together to develop a PBT plan for each facility. Facility/program characteristics that facilitate tracking family units to release group. – Lumping production to release. – Large release group sizes. – Release group size in intervals of your largest group of intact family units. Even with less than ideal circumstances a large proportion of family units can be tracked to release group resulting in a high “PBT tagging rate”. These same strategies could be employed at a finer scale, such as experimental unit, as well. Get creative, you would be surprised at what can be accomplished in maximizing the opportunities to utilize PBT.

Acknowledgments IDFG Genetics Lab – Matt Campbell – Craig Steele Hatchery Staff – Clearwater, Dworshak National, Hagerman National, Magic Valley, Niagara Springs fish hatcheries. PSMFC Marking Crew Stuart Rosenberger –IPC Brian Leth

Questions?