Pectoral Sandpiper

Bird of the Month: Pectoral Sandpiper

By Andy McCormick

PC: Mick Thompson (Pectoral Sandpiper)

PC: Mick Thompson (Pectoral Sandpiper)

Scientific Name: Calidris melanotos

Length 8.75 in

Wingspan 18 in

Weight 2.6 oz (73 g)

AOU Band code PESA

The Pectoral Sandpiper is uncommon in Western Washington but can usually be seen during fall migration. Adults begin passing through Washington in late July and juveniles show up from mid-August to late October. The juveniles will be in new plumage having completed their prejuvenile (or first prebasic) molt, which results in the change from downy feathers to their basic plumage. The juveniles will have a bright look with sharply defined markings on their feathers. The adults on the other hand will look worn, because they wait until they are on the wintering grounds to molt. 

The Big Bib Look

In both adult and juvenile Pectoral Sandpipers prominent streaking on the breast contrasts sharply with the clear white belly (Alderfer). This chest streaking appears heavy and has been described as looking like corduroy (Dunne). It is present in all plumages and is darker in the male. The Pec is a chunky-looking sandpiper that can appear a bit top-heavy. It has a dark bill with a pale base and yellowish, sometimes greenish-tinged, legs. 

The Pectoral Sandpiper is in the genus Calidris, from the Greek kalidris, used by Aristotle for a speckled waterbird. Its species name melanotos refers to its black-looking back in breeding plumage; from the Greek, melas, black and noton, back. Pectoral refers to this sandpipers chest sacs, which when inflated, are used to increase the resonance in its mating call (Holloway). 

Arctic Breeder

The breeding display of the Pectoral Sandpiper produces one of the most unusual sounds among shorebirds. The male’s inflatable chest sacs produce a hollow-sounding hooting call during flight displays. The Pec breeds along the Bering Sea and the northern arctic coastal plain across Northern Canada to Hudson Bay. 

Its nest is a shallow depression on the tundra usually well-hidden in grass. As is typical for shorebirds, four whitish to olive-colored eggs are deposited. Incubation is by the female only and lasts about three weeks. The young leave the nest soon after hatching and first flight is in another three weeks. Their diet consists primarily of insects. 

20,000 Mile Migration

Migration for the Pectoral Sandpiper is a long distance event. Pecs leave the breeding area quickly in mid-July and move to subarctic wetland staging areas before beginning a migration that takes them from northern Canada, Alaska and Siberia to southern South America, Australia and New Zealand. Some of these birds make a 20,000 mile trip. Most Pectorals keep to Central North America but juveniles will spread east and west to the coasts (Farmer, et al). 

Abundance estimates for Pectoral Sandpipers vary widely and they have proven to be a difficult species to study because the breeding grounds are very far north and the birds disperse widely after breeding. However, numbers in a variety of survey areas have been steady in the decades since the 1970s. There are no specific conservation measures being taken, but the habitat protection work of the Western Hemisphere Shorebird Reserve Network will be beneficial (Farmer, et al).