Banded snowy plover chick in depression with oyster shell. Credit: SFBBO
Banded snowy plover chick in depression with oyster shell. Credit: SFBBO

The San Francisco Bay Bird Observatory (SFBBO), USFWS Don Edwards San Francisco Bay National Wildlife Refuge (Refuge), California Department of Fish and Wildlife (CDFW), Hayward Area Recreation and Park District (HARD), East Bay Regional Park District (EBRPD), USFWS Bay Delta Fish and Wildlife Office, USDA-Wildlife Services, and Vollmar Natural Lands Consulting form the Western Snowy Plover (Charadrius nivosus nivosus; Snowy Plover) Recovery Unit 3 working group. The goal of this collaboration is to survey managed ponds and other habitats for Snowy Plovers, track breeding success, and contribute to the management and recovery of this species in the San Francisco Bay. During the 2022 breeding season, SFBBO monitored Snowy Plover population size, nesting and fledging success, the use of experimental habitat enhancement sites, and potential predators.

As part of the Pacific Coast breeding season window survey (May 16-22), we counted 263 adult Snowy Plovers in the San Francisco Bay. Over the course of the breeding season (March-September), SFBBO staff determined and documented the fates of 209 Snowy Plover nests in Recovery Unit 3, with 207 located in the South Bay and two located in San Pablo Bay. EBPRD documented the fate of three Snowy Plover nests at Hayward Shoreline. Vollmar Consulting Biologists documented the fate of two nests at Montezuma Wetlands in Suisun Bay near the Sacramento-San Joaquin Delta. Of the total nests, 48% were depredated, 3% abandoned, 2% unknown, 1% flooded, and 1% failed to hatch. Apparent nest success (defined as the percentage of nests that successfully hatched at least one egg out of the total nests monitored) was 45%.

Associated File(s)
Download Document PDF - western_snowy_plover_monitoring_in_the_san_francisco_bay_annual_report_2021.pdf (4.97 MB)