Semipalmated sandpiper Calidris pusilla

Identification Tips:

• Very small shorebird
• Short, thin, dark bill not obviously thinner at tip than at base
• Dark legs
• Thin, white wing stripe
• Black line on rump extends onto tail
• Sexes similar

Adult alternate:

• Black back feathers and wing coverts with gray edges
• Some black streaking on breast
• White underparts
• Indistinct white supercilium, gray crown and cheeks

Adult basic:

• Back and wing coverts gray with narrow black centers
• Faint, partial gray breast band
• White underparts
• Indistinct white supercilium, gray crown and cheeks

Juvenile:

• Black-based back feathers and wing coverts with white and gray edges
• May have faint orangish wash to upperparts and breast
• Faint, partial gray breast band
• White underparts
• Dark crown contrasts with pale supercilium

Similar species:

The Semipalmated Sandpiper is one of a group of very similar small shorebirds called "peeps". The Sanderling is obviously larger with a bolder wing stripe. White-rumped and Baird's Sandpiper are larger and appear especially longer-winged. Least Sandpiper is browner, has yellow legs (unless stained by mud), and a slightly decurved bill. Western Sandiper is most similar and is told in alternate plumage by its rufous upperparts and in juvenile plumage by its rufous scapulars. In basic plumage and in-between plumages note that the Western often has an obviously longer, thinner-tipped bill with a droop at the tip, a more square-shaped head, and sometimes retains a few dark chevrons on the flanks. The juvenile Semipalmated Sandpiper has a darker crown than the basic plumage Western Sandpiper. The very rare Little and Rufous-necked Stints are more rufous in alternate and juvenile plumages, the Semipalmated lacking any rufous coloration. In basic plumage, they are very similar (see Jonsson & Grant, 1984).