Non-invasive estimation of minimum population sizes and MHC variability in the Andean condor

ALCAIDE, M.; CADAHÍA, L.; LAMBERTUCCI, S. A.; NEGRO, J. J.

THE CONDOR

Cooper Ornithological Society

Lugar: Oklahoma, USA; Año: 2010 vol. 112 p. 470 - 478

0010-5422

Estimating abundance indices of threatened species is crucial to preserve biodiversity. During the last decades, non-invasive genetic sampling has proven to be a straightforward and relatively inexpensive approach compared to capture-mark-recapture analyses. In particular, molted feathers have become extremely popular for the monitoring of bird populations. Diagnostic molecular markers such as microsatellites, however, are still not available for many avian species of conservation concern. Highly polymorphic MHC genes, on the other hand, have become reasonably accessible during the last few years. The suitability of MHC profiles as individual DNA fingerprints to assist individual identification was tested in a scavenger species difficult to monitor through traditional approaches, the Andean Condor (Vultur gryphus). To achieve this aim, we isolated polymorphic and putatively functional MHC class I (exon 3, 6 alleles) and MHC class II B genes (exon 2, 11 alleles). Single Strand Conformational Polymorphism (SSCP) and direct sequencing analyses of MHC variation, combined with molecular sexing and age class inferred from feather color, allowed us to identify 80 different individuals from 110 molted feathers collected at roosts sites. Inferred sex and age ratios were concordant with previous studies relying on direct observations. The number of adult males doubled that of adult females and sex ratios were inverted in the case of juveniles. Besides providing valuable data regarding genetic variation at functionally important genes related to pathogen resistance, we demonstrate additional potentials of polymorphic MHC loci beyond their well-known role in evolutionary ecology. Non-invasive estimation of minimum population sizes and MHC variability in the Andean condor.