AFSC/ABL: 1996 Brood year Steelhead growth and early life-history transitions

Metadata Updated: November 17, 2018

Heritabilities of growth, precocious maturation and smolting were measured in 75 families of juvenile steelhead or rainbow trout Oncorhynchus mykiss, progeny of within and between line matings (crosses) of wild, anadromous steelhead and wild, resident (lake) rainbow trout originally derived from the same anadromous stock 70 years earlier. The tagged yearling progeny were combined by line in common freshwater rearing containers and graded into three categories: mature, smolt or rearing (undifferentiated) at age 2 years. Heritabilities of precocious male maturity, smolting and growth were moderate to high, and the genetic correlation between growth and smolting was low. Smolting and precocious male maturity were highly variable among families within lines and significantly different between lines. Each of the four lines produced significant numbers of smolts at age two. Smolting and maturation were negatively genetically correlated, which may explain the persistence of smolting in the lake population despite strong selection against lake smolts; balancing selection on male maturation age may help to maintain variation for smolting. The high heritability of smolting, coupled with the inability of smolts that leave the lake to return to it indicates that the genetic potential for smolting can lie dormant or be maintained through a dynamic interaction between smolting and early maturation for decades despite complete selection against the phenotype. The results have significant implications for the preservation of threatened anadromous stocks in fresh water and the inclusion of resident fish of formerly anadromous populations, currently trapped behind long-standing barriers to migration, as one component of the same population.

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Dates

Metadata Date February 28, 2018
Metadata Created Date May 31, 2016
Metadata Updated Date November 17, 2018
Reference Date(s) December 1, 2004 (publication)
Frequency Of Update notPlanned

Metadata Source

Harvested from NOAA CSW Harvest Source

Additional Metadata

Resource Type Dataset
Metadata Date February 28, 2018
Metadata Created Date May 31, 2016
Metadata Updated Date November 17, 2018
Reference Date(s) December 1, 2004 (publication)
Responsible Party Alaska Fisheries Science Center (Point of Contact, Custodian)
Contact Email
Access Constraints Access Constraints: Contact the Point of Contact for data request form. The Data set is still being analyzed and will not be available for distribution until it has been finalized and all QA/QC practices have been performed. Contact the Data Point of Contact for estimated time of release. | Use Constraints: User must read and fully comprehend the metadata prior to use. Data should not be used beyond the limits of the source scale. Acknowledgement of NOAA, as the source from which these data were obtained, in any publications and/or other representations of these data is suggested.
Bbox East Long -134.6333
Bbox North Lat 56.39417
Bbox South Lat 56.38417
Bbox West Long -134.6433
Coupled Resource
Frequency Of Update notPlanned
Guid gov.noaa.nmfs.inport:17262
Harvest Object Id 3e1760ce-83aa-40e0-a9ef-288919f27b54
Harvest Source Id 2aed8e29-fc5b-4cde-aa66-fb1118fd705e
Harvest Source Title NOAA CSW Harvest Source
Licence
Metadata Language eng
Metadata Type geospatial
Progress completed
Spatial Data Service Type
Spatial Reference System
Spatial Harvester True
Temporal Extent Begin 1996
Temporal Extent End 1998

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