Semipalmated sandpipers breed from late May to July. Upon arriving at the breeding grounds, males establish territories from which to display to females arriving about a week later. Males perform aerial displays at 5 to 9 m where they hover and produce "motorboat" calls. These aerial displays are well suited to their relatively open habitat where visibility is high. The male excavates up to 10 to 12 scrapes among sparse vegetation within his territory for females to choose from. The female will then select 2 to 3 of these scrapes (although only one is used) to begin lining with vegetation and other organic matter. Semipalmated sandpipers form monogamous pairs.
Mating System: monogamous
Semipalmated sandpipers breed from May through July. After mating, the male defends the territory while the female lays eggs in the nest. Females typically lay 3 to 4 eggs per brood in 24 to 32 hour intervals. Incubation of the eggs, which is done by both parents, lasts 18 to 22 days. Like all scolopacids, semipalmated sandpipers are precocial at birth and begin actively foraging within hours of hatching. The young fledge 16 to 19 days after hatching. Semipalmated sandpipers reach sexual maturity at 1 year old.
Breeding interval: Semipalmated sandpipers produce one brood per year.
Breeding season: Semipalmated sandpipers breed from May to July.
Range eggs per season: 3 to 4.
Average eggs per season: 4.
Range time to hatching: 18 to 22 days.
Range fledging age: 16 to 19 days.
Average fledging age: 19 days.
Average age at sexual or reproductive maturity (female): 1 years.
Average age at sexual or reproductive maturity (male): 1 years.
Key Reproductive Features: seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate)
Semipalmated sandpipers provide parental care for their young starting with incubation by both parents. Incubation lasts 20 to 22 days. Both parents participate in feeding and protecting the young for up to 11 days. Between 6 to 11 days after the chicks hatch the parents abandon the brood at separate times with the female being the first to leave nearly 91% of the time. Females stay with their young on average 6 days after they are hatched then leave their young to be provided for by their mate. The male continues to make a night scrape for the young for 6 to 8 days after hatching. The male abandons the brood on average 8 days after female, regardless of whether or not chicks have fledged.
Parental Investment: precocial ; male parental care ; female parental care ; pre-fertilization (Provisioning, Protecting: Male, Female); pre-hatching/birth (Provisioning: Male, Female, Protecting: Male, Female); pre-weaning/fledging (Provisioning: Male, Protecting: Male); pre-independence (Provisioning: Male, Protecting: Male)