The Semipalmated Plover takes its name from the partial webbing between its toes. It is one of the most common of the migrating small plovers. It migrates from the Arctic to the southern tip of South America, with a number of birds wintering on U.S. coasts south of Washington and south of Pennsylvania.
This plover can be seen in the Edmonds Marsh during both northbound and southbound migrations. It is more common on the outer coast than in the inland marine waters. Peak times for this migrant are mid-April through May and then July through September.
Superficially, the Semipalmated Plover resembles the Killdeer that is an Edmonds resident. This plover is overall smaller than a Killdeer and sports a single black breast band instead of the double black bands of the Killdeer.
In migration, the Semipalmated Plover seeks out open habitats such as mudflats, salt marshes, sandy beaches, and lake shores. Sometimes it can be found in flooded or plowed fields with other shorebirds. On its northern breeding grounds it uses gravel bars along sea coasts, rivers or ponds.
Diet varies with the season. During the breeding season, and for those birds that migrate inland, this plover feeds mostly on insects such as flies and their larvae, as well as earthworms. On the coast it eats marine worms, crustaceans and small mollusks. Unlike other shorebirds, plovers find their prey by sight. For that reason they have large eyes. They run a few steps, pause, then run again, pecking at the ground when they see something edible. When it finds a worm, the struggle between bird and worm can look like a tug-of-war.
The male’s courtship display involves flying over its territory in wide circles with slow wingbeats, calling repeatedly. On the ground, the male will crouch with its tail spread, wings open, and feathers fluffed, uttering excited calls. The nest is nothing more than a shallow scrape on bare ground or open gravel or sand. Sometimes it is placed near a large rock or other landmark.
There are typically four eggs that are incubated by both sexes for 23-25 days. The downy young leave the nest soon after hatching. Both parents tend the young birds but they are on their own to find all of their food. The young take their first flight at about 23-31 days of age.
The oldest recorded Semipalmated Plover was at least nine years and two months of age when recaptured during a Massachusetts banding operation. A collective noun for any group of plovers is congregation.
Unrestricted shooting in the late 19th century depleted the Semipalmated Plover population. It rebounded in the 20th century and it is one of the few plover species whose numbers are increasing. This may be due to its versatility and wide-spread coastal distribution in winter. For conservation purposes it is considered a species of least concern.
— By Carol Riddell
Carol Riddell manages the bird education displays, on behalf of Pilchuck Audubon Society and Edmonds Parks & Recreation, at the Olympic Beach Visitor Station.