AFSC/ABL: 1996 Brood year Steelhead growth and early life-history transitions
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.
Complete Metadata
| @type | dcat:Dataset |
|---|---|
| accessLevel | non-public |
| contactPoint |
{
"fn": "Gray, Andrew",
"@type": "vcard:Contact",
"hasEmail": "mailto:andrew.gray@noaa.gov"
}
|
| describedByType | application/octet-steam |
| description | 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. |
| distribution |
[
{
"@type": "dcat:Distribution",
"title": "NOAA Data Management Plan (DMP)",
"mediaType": "placeholder/value",
"description": "NOAA Data Management Plan for this record on InPort.",
"downloadURL": "https://www.fisheries.noaa.gov/inportserve/waf/noaa/nmfs/afsc/dmp/pdf/17262.pdf",
"describedByType": "application/octet-steam"
},
{
"@type": "dcat:Distribution",
"title": "GCMD Keyword Forum Page",
"mediaType": "placeholder/value",
"description": "Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 22. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords",
"downloadURL": "https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords",
"describedByType": "application/octet-steam"
},
{
"@type": "dcat:Distribution",
"title": "Full Metadata Record",
"mediaType": "placeholder/value",
"description": "View the complete metadata record on InPort for more information about this dataset.",
"downloadURL": "https://www.fisheries.noaa.gov/inport/item/17262",
"describedByType": "application/octet-steam"
}
]
|
| identifier | gov.noaa.nmfs.inport:17262 |
| issued | 2004-12-01T00:00:00.000+00:00 |
| keyword |
[
"AK",
"Alaska",
"Little Port Walter",
"Oncorhynchus mykiss",
"growth",
"heritability",
"maturation",
"precocious",
"smolting",
"steelhead",
"DOC/NOAA/NMFS/AFSC > Alaska Fisheries Science Center, National Marine Fisheries Service, NOAA, U.S. Department of Commerce",
"Auke Bay Laboratories"
]
|
| landingPage | https://www.fisheries.noaa.gov/inport/item/17262 |
| language |
[]
|
| license | https://creativecommons.org/publicdomain/zero/1.0/ |
| modified | 2004-12-01T00:00:00.000+00:00 |
| publisher |
{
"name": "Alaska Fisheries Science Center",
"@type": "org:Organization"
}
|
| references |
[
"https://www.fisheries.noaa.gov/inportserve/waf/noaa/nmfs/afsc/dmp/pdf/17262.pdf"
]
|
| rights | otherRestrictions, unclassified |
| spatial | -134.6333,56.38417,-134.6433,56.39417 |
| temporal | 1996-01-01T00:00:00+00:00/1998-01-01T00:00:00+00:00 |
| title | AFSC/ABL: 1996 Brood year Steelhead growth and early life-history transitions |
