Courtesy Kenn Kaufman
The Purple Sandpiper breeds around the Arctic Circle in an uneven distribution. In the Canadian Arctic, it ranges from Banks Island in the west to the eastern end of Baffin Island in the east. In North America, populations winter from Newfoundland to South Carolina.
A legend for the range map to the right can be found here
Breeding Purple Sandpipers use a variety of habitats on the arctic tundra: gravel beds, the edges of frozen ground, and heath meadows. During migration and winter, this sandpiper uses rocky shoreline almost exclusively, especially where the tidal action is strong, winds are light, and temperatures are cool to cold.
Walking, hopping, and clambering over rocks and tundra, the Purple Sandpiper picks prey items from various surfaces. The breeding diet consists of springtails (flightless insects that live in the soil), flies, aphids, spiders, marine worms, seeds, and berries. The winter diet shifts to include mussels, crustaceans, and beetles.
Purple Sandpipers form long-term monogamous pairs that re-form each breeding season. As snow begins to melt on the tundra, males arrive to establish territories with flight displays, aggressive sparring. chasing, and “fencing,” or running parallel to each other. Courtship includes flight displays, and close chasing. Purple Sandpipers locate nests in tundra with moderate to dense cover. Leaves, sedges, and heather form the base of the nest, which is often lined with down.
For about three weeks, Purple Sandpipers share the incubation of four light greenish eggs, variably marked with dark brown and grey. Their eggs are hardy and can survive without incubation for about a day. Upon hatching, chicks are able to walk, feed themselves, and preen; after a few days, they no longer need brooding, and the females usually depart at this time. Males tend to the young for approximately three weeks, until the juvenile Purple Sandpipers can fly well and form flocks for foraging and migration.
Migration in Purple Sandpipers varies with population. On Greenland, this species appears resident, but other populations migrate between 60 and 2,200 miles. Their large, dense flocks depart the latest among fall shorebirds. Southbound Purple Sandpipers depart after molting and according to age and sex: females leave first, then males, and finally juveniles. This pattern is reversed in the spring.