Habitat
Stilt Sandpipers nest in moist meadows and on drier slopes in low arctic and subarctic tundra. In subarctic areas they nest among dwarf birch, dwarf willow, Lapland rosebay, bog rosemary, bearberry, bog blueberry, and mountain cranberry, along with scattered, stunted black spruce. Farther north, they occupy similar habitats but also dry tundra slopes with extensive dwarf willow. Migrants gather mostly in freshwater environments such as marshes, ponds, and rainwater pools, but they also frequent flooded pastures, wet agricultural fields, and impoundments. They rarely forage on sandy beaches or in saltwater habitats such as lagoons or mudflats. On wintering grounds in central South America, Stilt Sandpipers use much the same habitats as on migration, but also saltworks, rice fields, and brackish swamps.
Back to topFood
Stilt Sandpipers eat mostly aquatic invertebrates such as beetles, snails, and insect larvae. They also eat plant matter such as seeds. Most of their foraging is tactile: they use the sensitive bill to probe for prey in mud as they wade slowly through water, often up to their bellies. They also sometimes hunt visually, picking prey from water, at or near the surface. Because they forage mostly by touch, Stilt Sandpipers often feed at night. Prey items include many sorts of beetles and their larvae, especially diving beetles, and adult and larval flies, craneflies, midges, mosquitoes, water bugs, water boatmen, small snails, and small frogs. They eat seeds of knotweed, river hemp, and many composite flowering plants (family Asteracaeae).
Back to topNesting
Nest Placement
The male makes several scrapes in the tundra from which the female selects the nest site, usually a natural depression or flat spot near dwarf birches or willows, and sometimes near water.
Nest Description
The nest is a simple depression lined with willow and birch leaves, grasses, sedges, cotton grass, horsetail, mosses, and lichens. Nests average about 4.1 inches across and 1.2 inches tall.
Nesting Facts
| Clutch Size: | 2-5 eggs |
| Egg Description: | Light green to olive green, with dark brown spotting. |
| Condition at Hatching: | Active and covered with down. |
Behavior
Male Stilt Sandpipers arrive on breeding grounds ahead of females, and they commence courtship displays as soon as females arrive. They chase females (sometimes several males in pursuit), then fly beyond the female, raise the wings in a V over the head, then fall toward earth, singing and rocking side to side before landing, then often raising one or both wings while standing. This display and song also serve to mark a breeding territory. Established pairs may dispense with courtship and territorial displays altogether; in fact, one research project saw no activity of adults at all until researchers noticed that an old nest had new eggs! Stilt Sandpipers are monogamous in their mating system, and some may mate for life. Male and female spend most of their time close by each other during the early part of the nesting season, until the female completes egg-laying. Males occasionally fly at and drive away other males (or other shorebird species) from the territory, or else use a threat display, holding one wing up. Territoriality wanes as soon as eggs are laid. The size of a territory varies tremendously, from 2.5 acres to much larger, but males seldom patrol or defend a large area and mostly ignore other birds once females have laid eggs. Adults share incubation duties, and both parents tend and defend young chicks, though males do most of this work and may even tend chicks from other pairs. During and after the nesting season, Stilt Sandpipers feed together in flocks. migrants and wintering birds also forage together with little evidence of aggression, unlike many other shorebird species. They rest and roost together or mixed with other shorebirds, often yellowlegs and dowitchers.
Back to topConservation
Stilt Sandpiper populations may be declining, but the extent of the decline is not known. Populations carefully studied from the 1960s to the present in northern Canada have apparently suffered from proliferation of nesting Snow Geese, which degrade the species’ nesting habitat. Density of breeding pairs there declined by almost 90% over a 30-year period. Partners in Flight estimates a global breeding population of 1.2 million birds and rates the species a 12 out of 20 on the Continental Concern Scale, indicating a species of low conservation concern. Petroleum and gas development in breeding areas and development of wetlands in wintering areas reduce habitat available to this species. Stilt Sandpipers are hunted in the Caribbean and South America. As for many species of birds that nest in the arctic and subarctic regions, changes in habitats and prey availability that result from climate change likely represent the chief conservation threats to Stilt Sandpiper.
Back to topCredits
Andres, B. A., P. A. Smith, R. I. G. Morrison, C. L. Gratto-Trevor, S. C. Brown, and C. A. Friis (2012). Population estimates of North American shorebirds, 2012. Wader Study Group Bulletin 119:178–194.
Klima, Joanna and Joseph R. Jehl Jr. (2012). Stilt Sandpiper (Calidris himantopus), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
Partners in Flight (2017). Avian Conservation Assessment Database. 2017.
Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.