Publications

We developed and tested a new protocol for sampling populations of the desert tortoise, Gopherus agassizii, a state- and federally listed species, in areas where population densities are very low, historical data are sparse, and anthropogenic uses may threaten the well-being of tortoise populations and habitat. We conducted a 3-year (2002–2004) survey in Jawbone-Butterbredt Area of Critical Enviro

No abstract available.

The perception is that today’s large fires are an ecological catastrophe because they burn vast areas with high intensities and severities. However, little is known of the ecological impacts of large fires on both historical and contemporary landscapes. The present paper presents a review of the current knowledge of the effects of large fires in the United States by important ecosystems written by

Water temperature influences many aspects of a salmon’s life cycle, including egg development, juvenile appetite and growth, migration, and distribution. Coho salmon (Oncorhynchus kisutch), like most salmonids, need cool water for rearing, and they typically reside in a stream for a minimum of one year after hatching. Historically, coho were found throughout most of the 67-mile (108-kilometer) mai

The California clapper rail (Rallus longirostris obsoletus) lives in remnant tidal marshes of San Francisco Bay, where less than 20 percent of the historic tidal wetlands remain. Listed as an endangered species in 1970 by the Fish and Wildlife Service (FWS), this enigmatic bird faces a myriad of threats, including habitat loss due to urban encroachment, sea-level rise caused by climate change, alt

For most large U.S. parks and wilderness areas, enabling legislation and management policy call for preservation of these protected areas unimpaired in perpetuity. Central to the notions of protection, preservation, and unimpairment has been the concept of maintaining “naturalness,” a condition imagined by many to persist over time in the absence of human intervention. As will be discussed below i

Parasites can have strong impacts but are thought to contribute little biomass to ecosystems. We quantified the biomass of free-living and parasitic species in three estuaries on the Pacific coast of California and Baja California. Here we show that parasites have substantial biomass in these ecosystems. We found that parasite biomass exceeded that of top predators. The biomass of trematodes was p

No abstract available.

We used satellite telemetry to determine the at-sea distribution of 32 adult (non-breeders and failed breeders) Grey-faced Petrels, Pterodroma macroptera gouldi, during July-October in 2006 and 2007. Adults captured at breeding colonies on the Ruamaahua (Aldermen) Islands ranged across the southwestern Pacific Ocean and Tasman Sea between 20-49°S and 142°E and 1300 W Petrels were located almost ex

We evaluated the impact of fire severity and related spatial and vegetative parameters on small mammal populations in 2 yr- to 15 yr-old burns in Yosemite National Park, California, USA. We also developed habitat models that would predict small mammal responses to fires of differing severity. We hypothesized that fire severity would influence the abundances of small mammals through changes in vege

Because sea otters (Enhydra lutris) exert a wide array of direct and indirect effects on coastal marine ecosystems throughout their geographic range, we investigated the potential influence of sea otters on the ecology of Bald Eagles (Haliaeetus leucocephalus) in the Aleutian Islands, Alaska, USA. We studied the diets, productivity, and density of breeding Bald Eagles on four islands during 1993–1

Small, rare and wide-ranging pelagic birds are difficult to locate and observe at sea; little is therefore known regarding individual movements and habitat affinities among many of the world's storm-petrels (Family Hydrobatidae). We re-located 57 of 70 radio-marked Ashy Storm-Petrels Oceanodroma homochroa captured at three colonies in the California Channel Islands: Scorpion Rocks (2004, 2005), Sa