Measurements
Both Sexes
- Length
- 7.1–7.9 in
18–20 cm - Wingspan
- 14.6–15.7 in
37–40 cm - Weight
- 1.2–1.8 oz
34–50 g
Relative Size
- Slightly smaller than a Killdeer
Other Names
- Chevalier grivelé (French)
- Playero coleador (Spanish)
Cool Facts
- The Spotted Sandpiper is the most widespread breeding sandpiper in North America.
- Female Spotted Sandpipers sometimes practice an unusual breeding strategy called polyandry, where a female mates with up to four males, each of which then cares for a clutch of eggs. One female in Minnesota laid five clutches for three males in a month and a half. This odd arrangement does not happen everywhere and often they are monogamous, with the female pitching in to help a little.
- The female Spotted Sandpiper is the one who establishes and defends the territory. She arrives at the breeding grounds earlier than the male. In other species of migratory birds, where the male establishes the territory, he arrives earlier.
- The male takes the primary role in parental care, incubating the eggs and taking care of the young. One female may lay eggs for up to four different males at a time.
- Despite the gender roles, male Spotted Sandpipers have 10 times the testosterone that females have. However, that’s only in absolute terms. During the breeding season, females see a sevenfold increase in their testosterone levels, perhaps accounting for their aggression and the overall role reversal between male and female.
- The female may store sperm for up to one month. The eggs she lays for one male may be fathered by a different male in a previous mating.
- Its characteristic teetering motion has earned the Spotted Sandpiper many nicknames. Among them are teeter-peep, teeter-bob, jerk or perk bird, teeter-snipe, and tip-tail.
- The function of the teetering motion typical of this species has not been determined. Chicks teeter nearly as soon as they hatch from the egg. The teetering gets faster when the bird is nervous, but stops when the bird is alarmed, aggressive, or courting.
Habitat
Shore-line
Spotted Sandpipers are the most widespread sandpiper in North America, and they are common near most kinds of freshwater, including rivers and streams, as well as near the sea coast. Their range includes water bodies in otherwise arid parts of the continent, and it extends into the mountains, where they may occur upwards of 14,000 feet above sea level. Breeding territories generally need to have a shoreline, a semiopen area where the nest will be, and patches of dense vegetation for sheltering the chicks. Spotted Sandpipers spend the winter along the coasts of North America or on beaches, mangroves, rainforest, and cloud forest up to 6,000 feet elevation in Central and South America.
Food
Small Animals
Spotted Sandpipers eat mostly small invertebrates such as midges, mayflies, flies (particularly their aquatic larvae), grasshoppers, beetles, worms, snails, and small crustaceans. They also eat small fish and may pick at dead fish as well. Spotted Sandpipers are active foragers—in addition to probing into sand or mud with their bills like most sandpipers, they also lunge at moving prey, pick insects off plants, or snap at airborne prey.
Nesting
Nesting Facts
- Clutch Size
- 3–5 eggs
- Number of Broods
- 1-5 broods
- Egg Length
- 1.1–1.4 in
2.9–3.5 cm - Egg Width
- 0.9–1 in
2.2–2.6 cm - Incubation Period
- 19–22 days
- Nestling Period
- 1 days
- Egg Description
- Off-white, pinkish, or pale green speckled with brown.
- Condition at Hatching
- Downy, coordinated, eyes open, and quickly able to begin eating and walking.
Nest Description
Nest building is an important part of courtship. A pair may begin several nests during the process, but those are rarely finished. The actual nest, built after the pair has formed and courtship is over, is a 2–3 inch depression scraped out in the soil and lined with dead grass and woody material. Often it is begun by the female and finished by the male.
Nest Placement
Ground
Either the male or the female may choose a nest location. Nests are always located near the edge of a body of water, usually within about 100 yards of the shore. The nest is typically placed under the shade of a broad-leafed plant. If predators are numerous, the nest is more likely to be under thicker vegetation such as raspberries or nettles. They are not averse to gravel pits, farm ponds, or even wetlands created by mining operations. They will often nest near or within Common Tern colonies when this species is present.
Behavior
Probing
Spotted Sandpipers are active foragers along streambanks and lake edges, walking in meandering paths and suddenly darting at prey—almost constantly bobbing their tail end in a smooth motion. Their flight style is equally distinctive: low over the water with stuttering bursts of fast wingbeats interspersed with very brief glides. Spotted Sandpipers were one of the first bird species described in which the roles of the males and females are reversed. Males are usually smaller, less aggressive and tend the nest and young. Meanwhile, the larger females fight for territories and may be polyandrous, meaning they mate with more than one male. Males that mate with the same female set up smaller territories within her territory and defend them against each other. Males tend to have more of the pituitary hormone prolactin than females. Prolactin promotes parental care, which may explain how the role reversal develops each season. The females perform courtship behavior, usually an elaborate swooping flight with the wings held open while the bird gives its weet-weet song. She may also give a strutting courtship display from the ground. Females that are looking for mates over a wide area may do this up and down considerable lengths of shoreline. Interested males remain on the territory while uninterested males are chased away.
Conservation
Least Concern
Spotted Sandpipers are the most widespread breeding sandpipers in North America and their populations are stable. On a local scale, development and loss of their wetland habitat or compromised water quality (from pesticides, herbicides, or other runoff) can harm their ability to feed and raise young.
Credits
- Oring, L. W., E. M. Gray, and J. M. Reed. 1997. Spotted Sandpiper (Actitis macularia). In The Birds of North America, No. 289 (A. Poole and F. Gill, eds.). The Birds of North America Online, Ithaca, New York.