Western Snowy Plovers (Part II): History and Problems

Part II – History and Problems

The Snowy Plover family goes back a long way. Their oldest fossils, found in Colorado and Belgium, date from about thirty million years ago, but some scientists think they’re at least ten million years older. The family currently is classified into about 67 species (debate continues) and found on all continents and many islands except Antarctica. Nine species breed in the continental U.S. and Canada; six species appear regularly in California, four at Surfrider. The Snowy is the smallest.

The entire world population of Western Snowy Plover (WSP) – about 4,000 birds - breeds exclusively on Pacific coastal beaches: about half in the U.S. from San Francisco southward, a few farther north, the rest in Baja California. After breeding they spread out in a post-breeding dispersal to winter on sandy beaches from Puget Sound south to Central America. There is also an inland race of Snowies numbering about 18,000 birds. Many of them winter with the WSPs in mixed flocks on western beaches. However, some evidence indicates that they might not interbreed, but go separate ways: WSPs to nest sites on coastal beaches; the interior race to inland sandy flats from California to Oklahoma, often adjacent to alkali lakes. If this is true, they are actually two separate species.

Population decline of WSPs was noticed many decades ago. Little was done until Pt. Reyes Bird Observatory (PRBO) became involved and did its first study of WSPs in 1977-80; results suggested that the birds had already disappeared from significant parts of their coastal California breeding range. Further studies were made. In 1993 WSPs were federally listed as threatened, and later listed as a Species of Special Concern by California. PRBO’s 1995 study showed a further 20% population decline since 1980.

In the late 1990’s local Malibu resident Mary Prismon, long-time member of Santa Monica Bay Audubon Society (SMBAS), began censusing the local WSP flocks at Zuma and Surfrider Beaches and reporting the results to PRBO. Her love for the birds enticed other SMBAS members to join her, until counting the birds and looking for bands became a regular part of the chapter’s activities.

In 2000, PRBO announced the first Winter Window Census of the California West Coast, set for mid-January 2001, coinciding with censuses in Washington and Oregon.  Mary asked me to help and, because no one else volunteered, I organized the Los Angeles County portion. I designed a protocol, divided the coastline into short segments, and found qualified volunteers to walk their segments on the same day at the same time. The weather was not good: the monthly high tide coincided with a storm surge. Nevertheless, the entire sandy beach of LA County, about 75 miles, was walked. The results were surprising.