Within-population variation in mating system and parental care patterns in the Sanderling (Calidris alba) in northeast Greenland

Abstract

ABSTRACT Sandpipers and allies (Scolopacidae) show an astounding diversity in mating and parental care strategies. Comparative studies have tried to interpret this variation in terms of phylogenetic constraints and ecological shaping factors. In such analyses, mating and parental care systems are necessarily discretely classified at the species level. The few available descriptive studies on breeding strategies of the Sanderling (Calidris alba) came to variable conclusions, which, in turn, were inconsistently used in these comparative studies. We provide empirical data on mating and parental care patterns in Sanderlings studied during six summers in northeast Greenland. In 135 clutches, we determined parental care from incubation profiles using temperature loggers and confirmed that both uniparental incubation by both sexes and biparental incubation (45 and 90 clutches, respectively) occurred. We used microsatellite-based parentage analyses to describe the degree of extrapair mating. In 48 completely assa...