Pilot Study for Aging Classification Criteria of Fledged Juvenile Eastern White-winged Doves

Abstract

Abstract Nineteen eastern white-winged doves Zenaida asiatica asiatica were hatched and raised in captivity and used to develop an aging key that 1) quickly identifies juveniles based on a series of morphological features, and 2) provides estimates of juvenile age based on primary feather replacement. Birds were photographed every three days from 17 to 170 d posthatch to determine sequence of primary flight feather replacement; persistence of juvenile secondary coverts; and development of blue eye ring, black neck bars, and leg color. Eleven birds exhibited adult features such as absence of buffy-tipped primary coverts, blue eye-ring color, complete black neck bar, and red leg color at day 170 posthatch; two birds had these features as early as day 122. Replacement of primary feathers was variable among individuals beyond day 35 beginning with the third primary. Primary feather (primary notation P1–P10) replacement occurred gradually. By day 170, 2 of 17 birds had replaced all primary feathers, 3 birds had fully molted P9 but not P10, 8 birds had begun molting P9 but not P10, and 4 birds did not molt either P9 or P10. Increased variability in primary feather replacement occurred as juveniles progressed toward adulthood; this precluded accurate age estimates of older juveniles based exclusively on primary replacement. The present study provides a better understanding of the molting process that wildlife managers, biologists, and researchers can use at hunter check stations or during trapping and banding operations to separate age classes, which is necessary to establish hunting frameworks and to assess the population effects of harvest and other mortality factors. This pilot study provides the foundation needed for further investigations into developmental patterns of fledged juvenile white-winged doves and provides an aging key that represents an improvement over previous white-winged dove aging keys or reliance on aging keys of closely related species.