Western Sandpiper
Calidris mauri

Physical Description 

• • Small birds, rather chunky in shape
  • Black legs, long thin black bill, and black eyes
  • Rusty-brown and black feathers on back, with white bellies
  • Females have longer bills than males

Range 

• • Their breeding habitat is northern Alaska and eastern Siberia
  • They migrate across most of western Canada and the United States
  • They spend the winters on the coastlines of the US and Mexico, and, rarely, in the interior of Mexico

Habitat

• • Sandpipers nest on the ground near dry vegetation
  • They forage for food in tidal estuaries, coastal lagoons, shorelines, ponds, river deltas, and saltmarshes
  • They always forage for food in very shallow water, often only a few inches deep

Diet

• • When we see them in La Jolla Shores, they are eating aquatic invertebrates, such as crustaceans, molluscs, plankton, and marine worms
  • Sandpipers also slurp the frothy “biofilm,” a mixture of diatoms, microbes, organic detritus, and sediment
  • Females have longer beaks, so they hunt by probing in the sand. Males hunt visually, by pecking and gleaning. Males are often hunting in more dry, shallow sand

Predators 

• • Red foxes, arctic foxes, long-tailed jaeger birds

Interesting Facts 

• • The male sandpipers make the nests and perform elaborate courtship displays for the females. Although the female looks like she is ignoring the male for several days, eventually she chooses the nest she approves of. All mating is monogamous, and about half of the same pairs nest together year after year.
  • Both the male and the female will sit on the egg to keep it warm and both will help defend the nest. The female will leave before the chick hatches, however, leaving chick-rearing to the male.
  • Western sandpipers are one of the most abundant shorebirds in North America with a population in the millions.

Sources: AllAboutBirds.org; Birds of North America.org; AnimalDiversity.org 

Photo: Thomas A. Blackman