Behavioural and genetic analyses of mate choice and reproductive success in two Chinook salmon populations
Canadian Journal of Fisheries and Aquatic Sciences
Sexual selection is recognized as an important evolutionary force in salmon. However, relatively little is known about variation in sexual selection pressures across salmon populations or the potential role of natural selection as a driver of adaptive mating patterns. Here, we examine mating behaviour and correlates of reproductive success in Chinook salmon (Oncorhynchus tshawytscha) from the Quinsam and Little Qualicum rivers in British Columbia, Canada - two populations for which we have previously found evidence of natural selection operating on major histocompatibility complex (MHC) genes. In both populations, males courted females and exhibited dominance behaviour towards other males, and the frequency of each behaviour was positively associated with reproductive success. Males were more aggressive towards females with whom they would produce offspring of low or high MHC class II diversity, and the offspring of males from the Quinsam River exhibited higher diversity at the MHC class I than expected. We discuss our results in relation to local natural selection pressures on the MHC and the potential for MHC-dependent mate choice.
Evans, Melissa L.; Neff, Bryan D.; and Heath, Daniel D.. (2013). Behavioural and genetic analyses of mate choice and reproductive success in two Chinook salmon populations. Canadian Journal of Fisheries and Aquatic Sciences, 70 (2), 263-270.