Arrival Time from Spring Migration in Male Pied Flycatchers: Individual Consistency and Familial Resemblance

Abstract

The timing of arrival from spring migration was studied in 4 years for male Pied Flycatchers (Ficedula hypoleuca) in central Spain. Heritability and repeatability analyses were performed at several levels of familial resemblance and male age in order to determine whether arrival times are consistent within individuals between years and are similar between relatives. Oldest males arrived earlier. Arrival time explained much of the variation in laying time and number of young fledged. Age-independent variation in wing length also affected arrival date, the males with longest wings settling earlier. Arrival times were not repeatable within individuals across years and were not similar between relatives (parents-sons, full-sibs). Although genetic variation may exist in departure dates of long-distance migrant birds, the close connection of an early arrival to high reproductive success may have depleted genetic variation in arrival time. In addition, environmental variation probably is too high to detect significant heritability in arrival times without very large sample sizes.