Chapter 12: Bird communities: effects of fragmentation, disturbance, and sea level rise on population viability
[Excerpt from Introduction] "The San Francisco Bay Estuary supports a large and diverse bird community. More than 50% of most Pacific flyway diving duck populations are found in the Estuary during the winter months (Trost 2002; U.S. Fish and Wildlife Service 2002). San Francisco Bay has been designated as a site of international importance for shorebirds (Western Hemisphere Shorebird Reserve Network), supporting millions of individuals (Morrison et al. 2001; Takekawa et al. 2001; Warnock et al. 2002), including species that use tidal marsh habitats. In total, the Bay’s tidal marshes support at least 113 bird species that represent 31 families (Takekawa et al., in press)..."
This datasets summarizes small mammal trapping efforts that USGS San Francisco Bay Estuary Field Station has led, co-led, or supervised, to detect and monitor the endangered salt marsh harvest mouse (Reithrodontomys raviventris) in the northern reaches of San Francisco Bay from 1998-2014. As the salt marsh harvest mouse is listed as endangered under the Endangered Species Act, sensitive location information can be made available upon request by contacting the dataset point of contact. These data support the following publication: Marcot, B.G., Woo, I., Thorne, K.M., Freeman, C.M., and Guntenspergen, G.R., 2020. Habitat of the endangered salt marsh harvest mouse (Reithrodontomys raviventris) in San Francisco Bay....
Habitat biogeochemistry was assessed by measuring 26 variables in sediments and porewater related to mercury content, organic matter, sediment characteristics, and microbial rates of sulfate reduction, iron reduction, and methanogenesis. Thirty-six composite surface (0-2 cm) sediment cores were collected in each of three wetlands in the spring and summer of 2005 and 2006.
Diet composition can be influenced by age- and sex-related factors including an individual’s morphology, social status, and acquired skills; however, specialization may only be necessary when competition is intensified by high population densities or increased energetic demands. The western sandpiper is a small (22-35 grams) migratory shorebird that exhibits female-biased sexual size dimorphism with a 5 percent greater body size and a 15 percent longer bill in females compared to males. It is considered a generalist with a diverse diet that includes benthic invertebrates and biofilm – a thin layer of microphytobenthos, bacteria, and detritus encased in a polysaccharide-rich matrix of extracellular polymeric substances...
Sediment biogeochemistry and subsequent mercury biomagnification in wetland food webs of the San Francisco Bay, CA
Methylmercury (MeHg) is a globally pervasive contaminant that biomagnifies in food webs and can reach toxic concentrations in consumers at higher trophic levels, including wildlife and humans. The production of MeHg, and its subsequent entry and biomagnification in food webs, is governed by a complex suite of biogeochemical, physical, and ecological processes, resulting in variation in the distribution of MeHg among regions and individuals. To better understand spatial variation in MeHg bioaccumulation within a species, we evaluated the effects of habitat biogeochemistry, food web structure, and diet composition in the wetland-obligate California black rail (Laterallus jamaicensis coturniculus) at three wetlands...
Mercury concentrations and stable isotope ratios for California black rails and their invertebrate prey from wetlands of the San Francisco Bay, CA
Methylmercury concentrations and stable isotope ratios were measured from back feathers of California black rails (Laterallus jamaicensis coturniculus) and six taxa of their invertebrate prey (Amphipoda, Arachnida, Coleoptera, Diptera, Gastropoda, and Hemiptera). Samples were collected from three wetlands in the spring and summer of 2005 and 2006.