Further notes on age of first breeding, plumage and biometrics of kelp gulls in South Africa

摘要

Adult kelp gulls Lams dominicanus vetula were caughtat the nest in the Eastern Cape region of South Africa,in October and November 2006 using a 'walk-in' trap. Inall, 13 previously ringed birds were re-trapped and aknown-aged colour-ringed bird was observed at a nestwith chicks. Two birds found breeding at the age ofthree years old were a year younger than the documented age of first breeding for this species. Plumage and soft part colouration used to age kelp gulls wasfound to be unreliable owing to individual variation.Biometric measurements were taken and fell largelywithin the published ranges for the species.