Semipalmated Sandpiper

The Semipalmated Sandpiper, Calidris pusilla, is a diminutive shorebird, a member of the family Scolopacidae. Its name is derived from the Latin 'pusilla', meaning 'very small', aptly describing its stature. This species exhibits a grey-brown plumage on its dorsal side, while its ventral side is predominantly white. The head and neck are suffused with a lighter grey-brown hue.

Identification Tips

Adult Semipalmated Sandpipers are recognized by their black legs and a short, stout, straight dark bill. With a wingspan of 35 to 37 centimeters, they are one of the smaller members of the sandpiper family. Distinguishing them from other 'peeps' or 'stints', particularly the Western Sandpiper, can be challenging due to their similar size and coloration.

Habitat

These birds breed in the southern tundra regions of Canada and Alaska, preferring areas in close proximity to water. Their nesting sites are on the ground, often lined with grass and other materials.

Distribution

The Semipalmated Sandpiper is a long-distance migrant, wintering along the coastal regions of South America, with some individuals reaching the southern United States and the Caribbean. They are known to migrate in large flocks, sometimes numbering in the hundreds of thousands.

Behaviour

During migration, Semipalmated Sandpipers congregate in significant numbers at key stopover habitats, such as the Bay of Fundy and Delaware Bay. They are highly dependent on these few critical areas for feeding and resting.

Song & Calls

The call of the Semipalmated Sandpiper is a soft, plaintive 'churp', often heard during its migratory flights or while foraging on mudflats.

Breeding

The female lays a clutch of 4 eggs, with both parents sharing incubation duties. Shortly after hatching, the female departs, leaving the male to care for the young, who are precocial and begin feeding themselves almost immediately.

Diet and Feeding

Semipalmated Sandpipers forage on mudflats, using both sight and tactile sensations with their bills to locate prey. Their diet consists of aquatic insects, larvae, spiders, snails, worms, and crustaceans. During spring migration, they rely heavily on horseshoe crab eggs. Females may also consume small mammal bones to supplement their calcium intake during egg laying.

Conservation status

The IUCN Red List currently classifies the Semipalmated Sandpiper as Near Threatened. Their reliance on a limited number of stopover sites makes them vulnerable to habitat loss and environmental changes. Conservation efforts are focused on protecting these critical areas, such as Mary's Point and Johnson's Mills along Shepody Bay, where the Nature Conservancy of Canada operates an information center to educate the public about these shorebirds.