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Michael L Casazza

Research Wildlife Biologist

Western Ecological Research Center

Office Phone: 530-669-5075
Fax: 707-678-5039
ORCID: 0000-0002-5636-735X

800 Business Park Drive
Dixon , CA 95620

Supervisor: Tom S Kimball
This USGS data release represents geospatial data for the sage-grouse habitat mapping project. This study provides timely and highly useful information about greater sage-grouse over a large area of the Great Basin. USGS researchers and their colleagues created a template for combining landscape-scale occurrence or abundance data with habitat selection data in order to identify areas most critical to sustaining populations of species of conservation concern. The template also identifies those areas where land use changes have minimal impact. To inform greater sage-grouse conservation planning, the researchers developed greater sage-grouse habitat management categories based on habitat selection indices (HSI) and...
[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)..."
California’s Central Valley is a nexus for water resources in the state, draining the Sacramento and San Joaquin River watersheds. Urban centers, agricultural operations, and the environment all compete for limited water, and demand is expected to only increase as the population grows and agriculture intensifies. At the same time, the water supply is projected to decrease as temperatures rise, precipitation patterns change, and the frequency of extreme droughts increases. The Central Valley also provides critical wetland habitats to migratory waterbirds, and wetland managers require information on how to best use water resources to support wildlife objectives, particularly during drought. This project seeks to...
Fragmentation and loss of natural habitat have important consequences for wild populations and can negatively affect long-term viability and resilience to environmental change. Salt marsh obligate species, such as those that occupy the San Francisco Bay Estuary in western North America, occupy already impaired habitats as result of human development and modifications and are highly susceptible to increased habitat loss and fragmentation due to global climate change. We examined the genetic variation of the California Ridgway’s rail ( Rallus obsoletus obsoletus), a state and federally endangered species that occurs within the fragmented salt marsh of the San Francisco Bay Estuary. We genotyped 107 rails across 11...
These data describe the location (terrestrial or aquatic) and activity status (active or inactive) of giant gartersnakes (Thamnophis gigas) by individual and location.
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