This week’s featured bird is the Spotted Sandpiper of the Shorebirds family. Many sandpipers breed only in the most northern parts of North America, but Spotted Sandpipers spend their summers across most of the continent.
Spotted Sandpiper (Actitis macularius)
Spotted Sandpipers are medium-sized shorebirds that have long tails and short necks. Their bills are slightly shorter their heads and they look like they are always leaning forward. Breeding adults have brown back, orange bills with a black tip, and yellow legs. True to their name, they have dark spots on their white bellies. They also have a white stripe above their eyes and on their wings during flight.. Nonbreeding “Spotties” (as they are sometimes called) have the brown backs but lack the bold belly spots. The sides of their breast are brown and more of a pinkish bill.
Summer (breeding): Canada to Alaska, Northern United States Migration: Southwest to Southeast United State Winter: Southern United States, Mexico, Caribbean Island, most of South America Year Round: Pacific Northwest Coast
Rocky shores, streams, lakes, ponds, mudflats. Typically found in fresh water environments. One of the most widespread sandpipers in North America
Invertebrates, insects, and small fish. They forage by probing at the mud of sand and lunging at moving prey.
Spotted Sandpipers have interesting breeding and nesting behaviors. In most bird species males are more aggressive and display courtship behaviors while females take care of the young. Spotted Sandpipers reverse these roles. Females will attract males by swooping flights where she makes a weet-weet call, or by strutting on the ground. They are usually monogamus, but some females may practice a breeding strategy called polyandry, where she may have up to four mates per season. She will leave the male to incubate and care for the eggs. Females also arrive earlier than males to choose a breeding site which she will defend. The nest, which is scraped out on the ground and lines with natural materials, is usually started by the female but finished by the male.
Spotted Sandpipers can have between 1 and 5 broods per year with a clutch size of 3-5 eggs. The male will incubate the eggs for 20-24 days. The chicks are precocial, so they leave the nest within hours of hatching able to walk and feed themselves. The young are usually tended to by the male and will take their first flights within 17-20 days of hatching.
Weet-weet call during breeding; a high whistled twii twii, a single peet
- Although male Spotties have 10 times more testosterone than females, female’s testosterone increases seven-fold during breeding, making the females more aggressive.
- A female can store sperm in her body for up to a month, so a male tending to her egg may not necessarily be the father of the chicks he’s caring for.
- Spotted Sandpipers are almost always doing a teetering motion, although scientists are not sure what purpose it serves.
- In flight, Spotties skim low over the water with a rapid burst of fastwingbeats, then have stiff short glides.
- Spotted Sandpipers are not usually seen in flocks. They are usually solitary.