Plumage development and moult in the European Quail Coturnix c. coturnix: criteria for age determination

Abstract

Sequence, rate and duration of moult were studied in captive bred European Quail Coturnix coturnix coturnix. The founder population originated from southwest France. The study was conducted between 1986 and 1989 on birds aged from 1 day to 2 years, exposed to a seasonal photoperiod corresponding to latitude 16°N during autumn and winter and latitude 48°N during the remainder of the year. Under these conditions, adult quail showed two annual moults with only the post‐breeding one being complete. The pre‐breeding moult essentially involved the throat feathers. Large interindividual variation was observed in the duration, timing and development of the post‐breeding moult: 60% of the studied birds suspended moult when they developed migratory restlessness and then finished renewing their feathers during the winter. The post‐juvenile moult was also suspended when 7–9 weeks old (3–6 primaries and 1–10 secondaries renewed). After this suspension, the length of which was related to the hatching date, the moult continued up to p7. The three outer primaries were kept for the first year and were replaced only during the post‐breeding moult. Based on the examination of wing patterns, our study provides reliable criteria for discriminating between age classes. The numbers of primaries and secondaries simultaneously in growth or renewed were different between the age classes. The secondaries of adults were renewed later in the moult stage than were the secondaries of juveniles. These criteria provide field researchers with a guide that enables them to age quail with reasonable accuracy.