The Pectoral Sandpiper is a medium-sized shorebird. It looks a lot like a Least Sandpiper but is about twice the size. It winters in South America and mostly passes through the eastern half of the U.S. on its way to and from its breeding grounds in the Arctic. Small numbers of this species migrate through Western Washington in April and May and then again in August and September.
A Pectoral Sandpiper or two often stop in the Edmonds marsh. The bird in the photos was on the beach near Shell Creek one September. But this sandpiper favors grassy marshes and wet fields. It is referred to as one of the “grasspipers” and was once known as the Grass Snipe.
Diet of the Pectoral Sandpiper seems to be mostly insects. On its tundra breeding grounds it feeds on flies and fly larvae, as well as beetles. It also eats amphipods, spiders, and some seeds. In migration its diet can include small crabs, other crustaceans, and other aquatic invertebrates. It forages by picking items from the surface of the ground or by probing in shallow water or mud.
The Pectoral Sandpiper got its current name from the male’s inflatable throat sac. He expands and contracts this feathered balloon during courtship display flights. He accompanies this display with a series of hollow hoots that have been described as one of the most unusual sounds of summer on the Arctic tundra. Both the male and female will take several mates. The male takes no part in caring for the eggs or young birds. The female builds her nest on the ground in grassy tundra. Sometimes it is near water but often it is at a dry upland site. The nest is nothing more than a shallow depression with a cup-shaped lining of leaves and grass. The female incubates her four eggs for about three weeks. The young leave the nest soon after hatching. The female tends her young while they feed themselves. Their age at first flight is about 21 days.
The oldest known Pectoral Sandpiper was 5 years and 11 months of age when it was found in El Salvador in 1983. It had been banded in 1978 in Kansas.
The Pectoral Sandpiper was abundant in the 19th Century, but market hunting greatly reduced its numbers. More recent migration surveys have shown a population decline since the 1980s. The most recent estimate of this shorebird’s population is 1.6 million. It was placed on the 2014 State of the Birds Watch List because it is at risk of becoming threatened or endangered in the absence of conservation efforts. Conservation activities began three years ago with the first World Shorebirds Day, celebrated each September 6th. Global shorebird counting activities take place between Sept. 2-6.
You can hear the call of a Pectoral Sandpiper at this link: http://www.xeno-canto.org/113150.
— 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.