Phenotypic plasticity plays a key role in modulating how environmental variation influences population dynamics, but we have only rudimentary understanding of interacts with the magnitude and predictability to affect dynamics persistence. We developed stochastic individual-based model, which phenotypes could respond temporally fluctuating cue fitness depended on match between phenotype randomly trait optimum, assess absolute dynamic consequences under different levels stochasticity...

Widespread population extirpations and the consequent loss of ecological, genetic, life-history diversity can lead to extinction evolutionarily significant units (ESUs) species. We attempted systematically enumerate extinct Pacific salmon populations characterize lost life history, genetic types among six species (Chinook [Oncorhynchus tshawytscha], sockeye [O. nerka], coho kisutch], chum keta], pink gorbuscha] steelhead trout mykiss]) from western contiguous United States. estimated that,...

Abstract We review the evidence for fisheries‐induced evolution in anadromous salmonids. Salmon are exposed to a variety of fishing gears and intensities as immature or maturing individuals. evaluate that is causing evolutionary changes traits including body size, migration timing age maturation, we discuss implications fisheries conservation. Few studies have fully evaluated ingredients evolution: selection intensity, genetic variability, correlation among under selection, response...

Seasonal timing of life-history events is often under strong natural selection. The Clock gene a central component an endogenous circadian clock that senses changes in photoperiod (day length) and mediates seasonal behaviours. Among Pacific salmonids ( Oncorhynchus spp.), migration breeding influenced by photoperiod. To expand study 42 North American Chinook salmon tshawytscha ) populations, we tested whether duplicated genes contribute to population differences reproductive timing....

The Ryman–Laikre (R-L) effect is an increase in inbreeding and a reduction total effective population size (NeT) combined captive–wild system, which arises when few captive parents produce large numbers of offspring. To facilitate evaluation the R-L for scenarios that are relevant to marine stock enhancement aquaculture, we extended original formula explicitly account several key factors determine NeT, including wild adults, ratio Ne/N (β), productivity breeders, removal individuals from...

Hatcheries are vital to many salmon fisheries, with inherent risks and rewards. While hatcheries can increase the returns of adult fish, demographic evolutionary consequences for natural populations interacting hatchery fish on spawning grounds remain unclear. This study examined impacts stray hatchery-origin pink population productivity resilience. We explored temporal assortative mating dynamics using a quantitative genetic model that assumed only difference between hatchery-...

Information developed during recently completed evaluations of the status seven species anadromous Pacific salmonids ( Oncorhynchus spp.) in Northwest was used to characterize patterns intraspecific diversity along three major axes: ecology, life history and biochemical genetics. Within study area, species’ ranges, therefore number distinct ecological regions inhabited differ considerably, with pink chum salmon limited northern areas chinook steelhead distributed over widest geographic...

Heritabilities of growth, precocious maturation and smolting were measured in 75 families juvenile steelhead or rainbow trout Oncorhynchus mykiss , progeny within between line matings (crosses) wild, anadromous resident (lake) originally derived from the same stock 70 years earlier. The tagged yearling combined by common freshwater rearing containers graded into three categories: mature, smolt (undifferentiated) at age 2 years. male maturity, growth moderate to high, genetic correlation was...

Abstract One of the most challenging problems in evolutionary biology is linking evolution phenotype with underlying genotype, because phenotypes are encoded by many genes that interact each other and environment. Further, correlated selection on one can affect other. This challenge especially important fishes, their response to harvest, global warming conservation actions among least understood aspects management. Here, we discuss two major genetic approaches studying complex traits,...

Life history traits of wild animals can be strongly influenced, both phenotypically and evolutionarily, by hunting fishing. However, few studies have quantified fishery selection over long time periods. We used 57 years catch escapement data to document the magnitude trends in gillnet on age size at maturity a commercially biologically important sockeye salmon stock. Overall, has caught larger fish than escaped spawn, but varied time, becoming weaker less consistent recently. Selection...

Whole genome duplication has been implicated in evolutionary innovation and rapid diversification. In salmonid fishes, however, whole significantly pre-dates major transitions across the family, re-diploidization a gradual process between genomes that have remained essentially collinear. Nevertheless, pairs of duplicated chromosome arms diverged at different rates from each other, suggesting retention regions through occasional pairing homeologous chromosomes may played an role species...

Captive breeding has the potential to rebuild depressed populations. However, associated genetic changes may decrease restoration success and negatively affect adaptive of entire population. Thus, approaches that minimize risks should be tested in a comparative framework over multiple generations. Genetic diversity two captive-reared lines species conservation interest, Chinook salmon (Oncorhynchus tshawytscha), was surveyed across three generations using genome-wide approaches. divergence...

Populations of the tree-hole mosquitoes Aedes geniculatus and A. triseriatus were cultured at different food levels larval densities to determine fitness consequences variation in these factors for each species. A composite index four correlates calculated population. Response-surface regression analysis indices indicated that two species have fundamentally responses density: The interaction quadratic effects had a strong influence on but little impact geniculatus. In both species, was most...

In 1976 chinook salmon (Oncorhynchus tshawytscha) gametes from the Chickamin and Unuk rivers in southeastern Alaska were transplanted 250 km to establish hatchery runs at Little Port Walter (LPW), Baranof Island. From 1977 1989, 1 862 058 marked smolts 12 broods released LPW. Homing straying estimated adult recoveries 25 locations British Columbia between 1981 1989. Of 22 198 LPW fish recovered over this period, 21 934 (98.8%) collected 264 elsewhere, 38.3% within 7 of LPW; 64.4% No...

We measured the additive genetic variance within populations and composite additive, dominance, epistatic effects contributing to differentiation of photoperiodic response between two southern (ancestral) each four progressively more northern (derived) pitcher-plant mosquito, Wyeomyia smithii. Critical photoperiod its but not heritability increased with latitude. Directional selection on critical during northward divergence W. smithii has therefore eroded underlying this trait. Joint scaling...

Abstract Parallel crosses between each of two southern (ancestral) and one northern (derived) population the pitcher-plant mosquito, Wyeomyia smithii, were made to determine genetic components divergence in critical photoperiod, a phenological trait that measures adaptation seasonality along climatic gradient. Joint scaling tests used analyze means variances first- second-generation hybrids order whether nonadditive variance, especially epistatic contributed photoperiod. In both crosses,...

Supplementing natural fish populations with artificially propagated (hatchery) is a common practice. In evaluating supplementation, it important to assess the relative fitness of both hatchery-produced and naturally produced when they spawn together in wild evaluate how absolute population changes after many generations supplementation. We evaluated coho salmon (Oncorhynchus kisutch) Minter Creek, Washington, USA. also long-term smolt production this stream several decades intensive hatchery...

Abstract Rainbow trout (Oncorhynchus mykiss) exhibit remarkable life history diversity throughout their native range, and among the most evident is variation in migratory propensity. Although some populations ecotypes will remain resident freshwater habitats history, others have ability to undertake tremendous marine migrations. Those that migrate undergo a suite of behavioral, morphological, physiological adaptations process called smoltification. We describe quantitative genetic analysis...