Patterns And Inlfuencing Factor Of Extra-Pair Copulations In The Yellow-rumped Flycatcher

Extra-pair copulations, is an important part of the Birds’ mixed reproductive strategies.The author conducted a study on the extra-pair copulations behavior in the Yellow-rumpedFlycatcher inside artificial nest box during March to July in2011and2012at Zuo JiaNatural Reserve Jilin province. The study including：the ratio and pattern of the extra-paircopulations, the sexual selection in extra-pair copulations is influenced by phenotypic traitsand genetic diversity or not and if nest spacing is an influencing factors of extra-paircopulations in the Yellow-rumped Flycatcher. In the study, we collected totalparent-offspring blood samples from31broods. including160offspring. we identifyextra-pair paternity by PCR amplification and microsatellite marker methods, and the resultof molecular experiment was analyzed through Cervus3.0software, Kingroup.V2softwareand SPSS17.0software. The results showed that the mating system of the Yellow-rumpedFlycatcher is critical monogamy and the rate of extra-pair copulations is high.21of31broods (67.7%) had extra-pair nestling, with38of160(23.8%) a result of extra-pairfertilizations. in the broods with extra-pair,32.8%nestlings was extra-pair fertilizations,every average broods had1.80±1.06(n=21) extra-pair nestling, variation range from1to5; every female mating with1.33±0.48(n=21) extra-pair mate, variation range from1to2;every extra-pair male mate with1.72±0.61（n=13）extra-pair mate, variation range from1to3.The result of the study on mechanism of the copulations in Yellow-rumped Flycatchershowed: the genetic similarity between extra-pairs are lower than society pairs; There wereno significant differences on genetic heterozygosity and body condition between Extra-pairmales and the social males they cuckolded. There were no significant differences on geneticheterozygosity and fitness between the EPY and WPY.The result of the study on influencing factor of extra-pair copulations in the Yellow-rumpedFlycatcher showed: There is not notability correlation between the extra-pair copulations andthe phenotypic trait such as body condition, part of the ornaments, and the reproductiveparameters such as Breeding time, clutch size, hatching period, hatching rate. The extra-pairsof Yellow-rumped Flycatcher may not be the nearest one, showed that the mate choice inYellow-rumped Flycatcher has selective...