Male reproductive competition in spawning aggregations of cod (Gadus morhua, L.)

@article{Bekkevold2002MaleRC,
  title={Male reproductive competition in spawning aggregations of cod (Gadus morhua, L.)},
  author={Dorte Bekkevold and Michael M{\o}ller Hansen and Volker Loeschcke},
  journal={Molecular Ecology},
  year={2002},
  volume={11}
}
Reproductive competition may lead to a large skew in reproductive success among individuals. Very few studies have analysed the paternity contribution of individual males in spawning aggregations of fish species with huge census population sizes. We quantified the variance in male reproductive success in spawning aggregations of cod under experimental conditions over an entire spawning season. Male reproductive success was estimated by microsatellite‐based parentage analysis of offspring… 
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It is hypothesized that energetic costs associated with reproduction, potentially mediated by sperm depletion in dominant individuals, may be responsible for temporal shifts in mating behaviour and reproductive success of male Atlantic Cod.
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Parentage Determination and Effective Population Size Estimation in Mass Spawning Pacific Oyster, Crassostrea gigas, Based on Microsatellite Analysis
TLDR
Seven high polymorphic microsatellite loci were used to determine the pedigrees in a mass spawning of Pacific oyster, Crassostrea gigas, and to estimate the genetic variability between broodstock and offspring, finding the higher inbreeding and lower effective population size should be considered.
Do cod form spawning leks? Evidence from a Newfoundland spawning ground
TLDR
Results add support to the hypothesis that cod employ a lekking mating system by indicating that both males and females were highly mobile while present on the spawning ground.
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