Dunlin, Calidris alpina
Dunlins are small shorebirds that breed and raise young in tundra and wetland habitats in the Arctic and subarctic regions of North America, Europe, and Asia from May to July.
During the breeding season, Dunlins are commonly found in more specific habitats like coastal tundra and wetlands, where the surroundings are characterized by open, grassy areas with freshwater ponds. Their primary diet consists of insects, insect larvae, small crustaceans, and aquatic invertebrates, which are abundant during this time.
They forage by probing their bills into the mud and sand of shallow water, picking out their prey with quick, precise movements. In addition to their primary diet items, they may also feed on small mollusks and plant matter. Dunlin bills curve slightly downward, allowing them to access prey hidden in the substrate of their wetland habitats.
Courtship in Dunlins involves elaborate aerial displays by the males, including fluttering flights and vocalizations. They form monogamous pairs during this period.
Nest building is done on the ground in grassy or mossy areas of the tundra. The nests are constructed using grasses, leaves, and twigs.
Females lay a clutch of four eggs, which are incubated primarily by the female. The male remains nearby to defend the nest. Upon hatching, the adults provide care to the chicks, feeding them a diet of small invertebrates.
As the chicks develop, they learn to forage under the guidance of the adults, refining their hunting skills. Vulnerabilities during this stage include predation by avian predators and exposure to harsh weather conditions.
Dunlin chicks fledge and gain independence, but they continue to receive guidance from the adults in finding suitable foraging areas and prey. Their diet expands as they gain experience.
Migration for Dunlins occurs in late summer and early fall. They follow specific flyways, migrating from their Arctic breeding grounds to wintering regions in coastal areas, estuaries, and mudflats in countries such as the United States, Mexico, and various parts of South America.
During the winter, Dunlins can be found in habitats like mudflats and coastal marshes. Their diet during this season consists of small crustaceans, worms, and mollusks, which are available in abundance.
Dunlins typically leave their wintering grounds and begin their northward migration in the spring, returning to their breeding areas in the Arctic and subarctic regions to commence another breeding season.