Sexing Icelandic Whimbrels Numenius phaeopus islandicus with DNA and biometrics

Whimbrels Numenius phaeopus are waders which exhibit no plumage difference between the sexes but some sexual size dimorphism exists, with females being on average larger than the males. During two breeding seasons in Iceland, 50 Whimbrels of the islandicus subspecies were caught on nests, measured and feather samples collected for DNA sexing. Generalised linear models were used to determine the utility of biometric data to sex the birds. Wing length and body mass were the only components that contributed significantly to the final model, which correctly predicted the sex of 76% of the birds sexed by DNA with at least 95% certainty.