Western Sandpiper

Calidris mauri

HOW TO IDENTIFY:

* Length: 5.25 inches
* Very small shorebird
* Short, thin, dark bill thinner at tip than at base and often with a slight droop
* Dark legs
* Thin, white wing stripe
* Black line on rump extends onto tail
* Sexes similar

Adult alternate:

* Rufous scapulars, crown and ear coverts
* Black back feathers and wing coverts with white edges
* Much black streaking and spotting on breast
* Black chevrons on flanks
* White underparts
* Indistinct white supercilium

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:

* Rufous scapulars
* Black-based back feathers and wing coverts with white and gray edges
* Faint, partial gray breast band
* White underparts
* Indistinct gray crown and pale supercilium

Similar species:

The Western 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 told from the similar Semipalmated Sandpiper 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 have rufous in the throat in alternate plumage, and lack the rufous scapulars in juvenile plumage. In basic plumage, they are very similar.