Publications

The Southeast Deserts Bioregion (desert bioregion) occupies the southeastern 27% of California (11,028,300 ha, 110,283 km2 or 27,251,610 ac) (Miles and Goudy 1997) (Map 18.1). The desert bioregion is within the basin and range geomorphic province of western North America, and includes two ecoregional provinces comprised of five ecological sections. The American Semi-Desert and Desert...

The Cosumnes River watershed requires a 57–64 percent reduction in loads to meet the new Delta methylmercury (MeHg) total maximum daily load allocation, established by the Central Valley Regional Water Quality Control Board. Because there are no large point sources of MeHg in the watershed, the focus of MeHg load reductions will fall upon non-point sources, particularly the expansive...

Striking faunal turnover across Asia and Australasia, most famously along the eastern edge of the Sunda Shelf or ‘Wallace's Line’, has been a focus of biogeographic research for over 150 years. Here, we investigate the origins of a highly threatened endemic lizard fauna (four species) on Christmas Island. Despite occurring less 350 km south of the Sunda Shelf, this fauna mostly comprises...

Great horned owls (Bubo virginianus) are widespread throughout North, Central, and parts of South America (Artuso et al. 2013). Across this range, great horned owls are generalists, occupying a diverse range of habitats including deciduous and coniferous forests, wetlands, and agricultural landscapes. Within these habitats, great horned owls are generally found near upland or short...

Context Transportation and wildlife agencies may consider the need for barrier structures and safe wildlife road-crossings to maintain the long-term viability of wildlife populations. In order to prioritize these efforts, it is important to identify species that are most at risk of extirpation from road-related impacts. Purpose Our goal was to identify reptiles and amphibians in...

No abstract available.

During surveys for Thamnophis gigas (Giant Gartersnake), I observed an adult T. sirtalis fitchi with unusual coloration— a yellow-cream background color with some typical red coloration laterally, but with very minimal amounts of the dark slate-black (along the sides of the yellow dorsal stripe and on top of the head) that normally predominates in this subspecies (Fig. 1; LACM [Natural...

No abstract available.

Forster’s terns (Sterna forsteri), historically one of the most numerous colonial-breeding waterbirds in South San Francisco Bay, California, have had recent decreases in the number of nesting colonies and overall breeding population size. The South Bay Salt Pond (SBSP) Restoration Project aims to restore 50–90 percent of former salt evaporation ponds to tidal marsh habitat in South San...

In the current context of environmental changes, it is easy to see how extrinsic factors, such as shifts in sea surface temperature, food availability and accumulation of pollutants, can impact the health of marine mammals. However, intrinsic factors, including the genetic constitution of an individual, are also largely responsible for shaping health, particularly in terms of immune...

The arroyo southwestern toad is a specialized and federally endangered amphibian endemic to the coastal plains and mountains of central and southern California and northwestern Baja California. It is largely unknown how long these toads live in natural systems, how their population demographics vary across occupied drainages, and how hydrology affects age structure. We used...

Worldwide, scientists have headstarted threatened and endangered reptiles to augment depleted populations. Not all efforts have been successful. For the threatened Agassiz's desert tortoise (Gopherus agassizii), one challenge to recovery is poor recruitment of juveniles into adult populations, and this is being addressed through headstart programs. We evaluated 8 cohorts of juvenile...