This species is distinctive in all plumages within the context of regularly-occurring North American shorebirds, especially during the breeding season when its underparts are extensively spotted with black. Its behaviour and, to a lesser extent, habitat choice (especially during the breeding season) are also distinctive in B.C.
Although it has not been recorded from B.C., the Common Sandpiper of Eurasia is a regular migrant through the Bering Sea islands of Alaska and has the potential to occur as a vagrant farther south along the Pacific coast of North America. It is similar to non-breeding and juvenile Spotted Sandpiper in all plumages (including breeding plumage) and can be very difficult to separate from that species without close observation. A juvenal-plumaged Common Sandpiper is the most likely plumage to be detected in B.C., and it is differentiated from similarly-plumaged Spotted Sandpiper by the following characteristics: 1) the relatively longer tail of Common Sandpiper, extending noticeably past the tips of the primaries during rest (tail tip extending only slightly past the end of the primaries in Spotted Sandpiper), 2) narrow but noticeable dark speckling along the entire edges of the tertials in Common Sandpiper (tertial edges mostly unmarked or sparsely spotted in Spotted Sandpiper), 3) more pronounced pale and speckled fringes to the scapular feathers of Common Sandpiper that contrast little with the pattern of the upperwing coverts (scapulars with few markings in Spotted Sandpiper, contrasting noticeably with the distinctly-marked upperwing coverts), and 4) the bolder and more extensive white wing stripe and white trailing edge to the secondaries of Common Sandpiper (less distinct and extensive in Spotted Sandpiper). Other minor, supporting characteristics include the duller, greener legs of Common Sandpiper (averaging brighter and often yellowish-tinged in Spotted Sandpiper) and the slightly browner upperparts of Common Sandpiper that contrast more noticeably with the white underparts (upperparts greyer and less contrasting in Spotted Sandpiper).
Source: Hayman et al. (1986); Paulson (1993)
| The most commonly heard call is the alarm call, which is given throughout the year from both perched and flying birds. This call is described as loud weet weet or peet peet peet, often extended into a prolonged tweet-weet tweet-weet-weet tweet-weet-weet-weet in flight. On the breeding grounds, both sexes give a similar prolonged series of weet notes in flight that functions as a song. Both sexes also give a sharp, loud spink or spink-spink alarm call near the nest or chicks. Other calls include a variety of softer wheet, peet-peet, kerrwee, and tootawee notes that are used as contact calls between the adults and chicks. The calls are similar to those of the Solitary Sandpiper, but are somewhat lower-pitched. Source: Oring et al. (1997) |
Courtship
The majority of courtship activities are performed by the female, who initiates courtship by acting aggressively towards the male (chasing him from her territory, etc.) before switching over to more reproductive-associated behaviours. The courtship displays include ground-based territorial singing, ritualized nest-building, aerial flight display, and a ground courtship display. During the aerial flight display, the female arches upwards and holds her wings steady and pointed downwards for several seconds, causing her to rise sharply in the air. Many females are polyandrous, and will begin to court additional males (either near her initial territory or elsewhere) shortly after laying a clutch.
Nest
Nest building is initiated during the courtship activities and often begins within minutes (at most, a day) of the male and female encountering each other. Both sexes construct several shallow scrapes in the ground and, once the pair bond is firmly established and insects are suitably abundant, finish one or two nests within the territory for the reception of eggs. The nest is a simple, shallow depression in the ground that is lined with grasses, forbs, twigs, wood chips, or needles from within the immediate vicinity of the nest; occasionally, nests are unlined. The nest is 11-13 cm across. Most nests are somewhat concealed by overhanging vegetation, logs, etc.
Eggs
Clutches of (1) 4 (6) eggs are laid between late April and early July (mostly in June), and the incubation period is (19) 20-22 (24) days. The female produces only one clutch per year with any given male, but may mate with several males over the course of the season and thus produce multiple (two or more) clutches. The male does the majority of the incubation, although the female will also assist on occasion (particularly with later clutches). The colour of the smooth, slightly glossy eggs ranges from off-white to pale buff (occasionally very pale greenish) with irregular dark purplish-brown or reddish-brown and pale grayish or purplish blotches and spotting. The last eggs have usually hatched in B.C. by late July.
Young
The young are fully precocial upon hatching and leave the nest immediately (although they will remain longer in the nest during bad weather, and may sometimes return during their first night). The young are attended by the male for approximately four weeks after hatching, although the female occasionally assists with some of the parental duties. The down-covered chicks are greyish-brown on the crown and upperparts and whitish on the throat and underparts (tinged grey on the sides of the neck and sides of the chest). There is a very narrow blackish line through the eye, extending from the base of the bill to the back of the ear coverts, and a similar dark streak runs from the centre of the crown down the nape and onto the back. The wing pads, sides of the back, rump, and long down of the tail have very narrow, broken blackish-grey bars. The down of the rump is long and protrudes as a wispy tuft. The chicks molt into their juvenal plumage at 16-18 days of age, and are capable of sustained flight at 18 days. Dates for chicks in B.C. range from mid-May to late August.
Source: Campbell et al. (1990b); Baicich and Harrison (1997); Oring et al. (1997)
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The Spotted Sandpiper typically forages on the ground in open habitats and consumes a variety of invertebrates (insects and their larvae, spiders, crustaceans) as well as, occasionally, small fish and tadpoles. It characteristically bobs its body when on the ground, especially when alarmed. It forages most often along the water’s edge or within 200 m of a water body, picking prey either from the surface of the ground, the surface of the water, or from low vegetation; regularly wades into shallow water. This species utilizes a variety of stitching, probing, or jabbing motions to capture prey, and has even been observed leaping into the air in pursuit of flying insects. It continually bobs its body while walking or foraging.
Source: Oring et al. (1997)
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