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Molecular Sexing of the Critically Endangered Slender-Billed Vulture Gyps Tenuirostris and its Conservation Implications


  • Bombay Natural History Society, Hornbill House, Dr. Salim Ali Chowk, S.B. Singh Road, Mumbai 400 001, Maharashtra, India
  • Centre for Wildlife Conservation, Management and Disease Surveillance, Indian Veterinary Research Institute, Izatnagar 243 122, Uttar Pradesh, India
  • Division of Veterinary Biotechnology, Indian Veterinary Research Institute, Izatnagar 243 122, Uttar Pradesh, India
  • School of Science, University of NMIMS (Deemed-to-be University), JVPD Scheme, Vile Parle (West), Mumbai 400 056, Maharashtra, India


The Slender-billed Vulture is probably the most endangered of the three resident Gyps vulture species of the Indian subcontinent, with a population of less than 1,000 individuals in the wild. A Conservation Breeding Programme was initiated by the Bombay Natural History Society (BNHS) to save this species from possible extinction. Sex identification of individuals is important to maintain the right sex ratio to maximize breeding success in the Conservation Breeding Programme. The Slender-billed Vulture is not sexually dimorphic, hence the applicability of polymerase chain reaction based (molecular sexing) methods for sex identification was assessed, and the first ever successful application of W-specific PCR combined with ZW-common PCR for sex identification in Slender-billed Vulture (n=12) was established. The PCR method was validated by comparing results with sex identification based on the study of breeding biology of nesting pairs. The reported molecular sexing method could prove a useful tool in management of Conservation Breeding Programmes, and also in determining the sex of dead birds collected from the wild during ecological studies.


Molecular Sexing, Sex Identification, Slender-Billed Vulture, W-Specific PCR, ZW-Common PCR.

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