NATURAL HISTORY

WESTERN SNOWY PLOVER } Charadrius alexandrinus nivosus
FAMILY: Charadriidae

DESCRIPTION: The western snowy plover is a very small bird, weighing less than two ounces and growing to be about six inches long. It is pale brown on top and white below, with a white hind neck collar, a dark forehead bar, and dark eye patches and lateral breast patches. Its legs and bill are dark gray or black. In breeding plumage, males usually have black markings on the head and breast, while females' patches are dark brown. In nonbreeding plumage, males and females look similar.

HABITAT: The bird lives in sandy coastal beaches, salt pans, coastal dredged spoils sites, dry salt ponds, salt pond levees and gravel bars. Nests typically occur in flat, open areas with sandy or saline substrates and sparse vegetation.

RANGE: The Pacific Coast snowy plover population ranges along the coasts of Washington, Oregon, California and Mexico, with the largest number of breeding birds occurring south of San Francisco Bay to southern Baja California.

MIGRATION: While some snowy plovers remain in their coastal breeding areas year-round, others migrate south or north for the winter. Most plovers that nest inland migrate to the coast.

BREEDING: The snowy plover nesting season extends from March to September. Breeding takes place primarily on coastal beaches from southern Washington to southern Baja California, beginning earlier in more southerly latitudes. A typical clutch contains three eggs, but two to six eggs are not unusual.

LIFE CYCLE: Snowy plover chicks leave the nest within hours to look for food, but are not able to fly for about four weeks. Fledging of late-season broods may extend into the third week of September. The average lifespan is about three years.

FEEDING: Snowy plovers are primarily visual foragers, feeding on invertebrates found in wet sand and amongst kelp washed up on the shore.

THREATS: Loss of nesting habitat and habitat degradation caused by expanding beach-front development, recreation and sea-level risee; human disturbance; off-leash dogs; encroachment of European beach grass on nesting grounds; pesticides; and predation threaten the species.

POPULATION TREND: In California, numbers increased from 976 breeding plovers in 2000 to 1,680 adult plovers in 2005. In Oregon, 23 of the bird's historic breeding sites had been lost by 1993, but four of are now reoccupied and numbers are growing. In Washington, only three out of five coastal nesting sites remain, but habitat conditions have improved and the number of breeding birds has at least remained steady and may have increased since listing. Overall, the U.S. portion of the Pacific Coast population is estimated to have increased from 1,500 birds in 1993 to approximately 2,300 birds in 2005.

Photo © Mike Baird