Breeding Biology of Wilson\u27s Plovers (Charadrius Wilsonia): Reproductive Success, Habitat Use, and Sex Roles

Understanding reproductive success rates and how a breeding pair achieves nest success is vital information needed for management of declining populations. Wilson’s Plover, a species of concern in most of the southeastern United States, has low hatching success on Cumberland Island National Seashore, a largely undeveloped island. However fledging success is high and an estimate of chicks produced per pair is near levels recommended by shorebird management plans. Wilson’s Plovers have strict incubation sex-roles tied to daylight. The female incubates most of the day while the male incubates most of the night. This division of labor has consequences for foraging opportunities, as male and female plovers are restricted to forage during day and night, respectively. This, in turn, has consequences for foraging success. Male Wilson’s Plovers spend more energy chasing prey during the day and are less successful than females foraging at night. Incubation consistency by each sex affects nest success with higher attendance and fewer movements associated with hatching. The primary cause of nest failure was predation. Weather also contributed to nest failure, but with annual variation dependent on large storms. Predator encounters were equal between night and day, but predator identity varied. Coyotes and raccoons were documented only taking nests at night while crows only depredated nests during the day. Understanding patterns of reproductive success in healthy habitats, and the behavioral ecology of adults of both sexes facilitates the development of sensible management plans