|
Vol. 50 No. 5, 2011
Determining the Sex of Reed Parrotbills Paradoxornis heudei from Biometrics and Variations in the Estimated Sex Ratio, Chongming Dongtan Nature Reserve, China
Anthony Boulord1,2, Xiao-Ting Yang2, Tian-Hou Wang2,*, Xiao-Ming Wang2, and Frédéric Jiguet1
1Muséum National d'Histoire Naturelle, UMR 7204 MNHN-CNRS-UPMC, CRBPO, CP 51, 55 Rue Buffon, Paris 75005, France
2CShanghai
Key Laboratory of Urbanization and Ecological Restoration, School of
Life Sciences, East China Normal Univ., 3663 N Zhongshan Rd, Shanghai
200062, China
Anthony Boulord, Xiao-Ting Yang, Tian-Hou Wang, Xiao-Ming Wang, and Frédéric Jiguet (2011) Differences in gender morphology of the near-threatened Reed Parrotbill Paradoxornis heudei
were analyzed to obtain equations discriminating individuals according
to sex. Results were used to define sex ratios during the breeding
period in both harvested and unharvested reedbeds. We caught 281
individuals and sexed them from biological criteria and by subsequent
observations of display behavior. A discriminant analysis was performed
on biometrics from 100 adults for which the sex was confirmed by a
genetic analysis, and then the predictive accuracy was tested with the
remaining individuals. The sex ratio of birds captured and its changes
during the nesting period were investigated in both harvested and
unharvested reedbeds. All tested parameters significantly differed
between sexes in adult Reed Parrotbills. Bill measurements displayed
the greatest sexual dimorphism. A discriminant function using bill
height and culmen length was derived which was found to correctly
identify the gender of 100% of tested individuals. This function will
be useful for rapidly sexing individuals in the field. The species
evidenced a balanced sex ratio in both harvested and unharvested areas.
This study provides supplementary evidence that the Reed Parrotbill
shares the same social system as the Vinous-throated Parrotbill P. webbianus and shows that harvesting activities do not seem to influence the sex ratio during the nesting period.
Key words: Reed Parrotbill, Biometric measurements, Sexual size dimorphism, Sex ratio.
*Correspondence: Tel: 886-21-62233021. Fax: 886-21-62861965. E-mail:thwang@bio.ecnu.edu.cn
|
