Skip to main content
U.S. flag

An official website of the United States government

Publications

Below is a list of WERC's peer-reviewed publications. If you are searching for a specific publication and cannot find it in this list, please contact werc_web@usgs.gov

Filter Total Items: 3618

An individual-based growth and competition model for coastal redwood forest restoration

Thinning treatments to accelerate coastal redwood forest stand development are in wide application, but managers have yet to identify prescriptions that might best promote Sequoia sempervirens (Lamb. ex D. Don) Endl. (redwood) growth. The creation of successful thinning prescriptions would be aided by identifying the underlying mechanisms governing how individual tree growth responds to competitiv
Authors
Phillip J. van Mantgem, Adrian J. Das

Sea otters are recolonizing southern California in fits and starts

After near extinction as a result of the fur trade in the 1700s and 1800s, the southern sea otter slowly reoccupied the core of its range in central California. Range expansion beyond central California is seen as key to full recovery of otters, but the rate of expansion has been sporadic, raising concerns about habitat quality in southern California. To describe the range expansion of sea otters
Authors
Kevin D. Lafferty, M. Tim Tinker

Adaptive nest clustering and density-dependent nest survival in dabbling ducks

Density-dependent population regulation is observed in many taxa, and understanding the mechanisms that generate density dependence is especially important for the conservation of heavily-managed species. In one such system, North American waterfowl, density dependence is often observed at continental scales, and nest predation has long been implicated as a key factor driving this pattern. However
Authors
Kevin M. Ringelman, John M. Eadie, Joshua T. Ackerman

Distribution, abundance, and migration timing of Greater and Lesser Sandhill Cranes wintering in the Sacramento-San Joaquin River Delta region of California

The Sacramento-San Joaquin River Delta region of California (hereafter, Delta region) is an important wintering region for the Central Valley Population of greater sandhill cranes (Grus canadensis tabida) and lesser sandhill cranes (G. c. canadensis), but basic information about the ecology of these birds is lacking to design a biologically sound conservation strategy. During the winters of 2007-0
Authors
Gary L. Ivey, Bruce D. Dugger, Caroline P. Herziger, Michael L. Casazza, Joseph P. Fleskes

Selection of anthropogenic features and vegetation characteristics by nesting Common Ravens in the sagebrush ecosystem

Common Raven (Corvus corax) numbers and distribution are increasing throughout the sagebrush steppe, influencing avian communities in complex ways. Anthropogenic structures are thought to increase raven populations by providing food and nesting subsidies, which is cause for concern because ravens are important nest predators of sensitive species, including Greater Sage-Grouse (Centrocercus urophas
Authors
Kristy B. Howe, Peter S. Coates, David J. Delehanty

Impacts of upper respiratory tract disease on olfactory behavior of the Mojave desert tortoise

Upper respiratory tract disease (URTD) caused by Mycoplasma agassizii is considered a threat to desert tortoise populations that should be addressed as part of the recovery of the species. Clinical signs can be intermittent and include serous or mucoid nasal discharge and respiratory difficulty when nares are occluded. This nasal congestion may result in a loss of the olfactory sense. Turtles are
Authors
Jennifer Germano, Vanessa E. Van Zerr, Todd C. Esque, Ken E. Nussear, Nadine Lamberski

Population declines lead to replicate patterns of internal range structure at the tips of the distribution of the California red-legged frog (Rana draytonii)

Demographic declines and increased isolation of peripheral populations of the threatened California red-legged frog (Rana draytonii) have led to the formation of internal range boundaries at opposite ends of the species’ distribution. While the population genetics of the southern internal boundary has been studied in some detail, similar information is lacking for the northern part of the range. I
Authors
Jonathan Q. Richmond, Adam R. Backlin, Patricia J. Tatarian, Ben G. Solvesky, Robert N. Fisher

Ghost of habitat past: historic habitat affects the contemporary distribution of giant garter snakes in a modified landscape.

Historic habitat conditions can affect contemporary communities and populations, but most studies of historic habitat are based on the reduction in habitat extent or connectivity. Little is known about the effects of historic habitat on contemporary species distributions when historic habitat has been nearly completely removed, but species persist in a highly altered landscape. More than 93% of th
Authors
Brian J. Halstead, Glenn D. Wylie, Michael L. Casazza

Behavioural cues surpass habitat factors in explaining prebreeding resource selection by a migratory diving duck

Prebreeding habitat selection in birds can often be explained in part by habitat characteristics. However, females may also select habitats on the basis of fidelity to areas of previous reproductive success or use by conspecifics. The relative influences of sociobehavioural attributes versus habitat characteristics in habitat selection has been primarily investigated in songbirds, while less is kn
Authors
Shawn T. O'Neil, Jeffrey M. Warren, John Y. Takekawa, Susan E. W. De La Cruz, Kyle A. Cutting, Michael W. Parker, Julie L. Yee

Vocal activity as a low cost and scalable index of seabird colony size

Although wildlife conservation actions have increased globally in number and complexity, the lack of scalable, cost-effective monitoring methods limits adaptive management and the evaluation of conservation efficacy. Automated sensors and computer-aided analyses provide a scalable and increasingly cost-effective tool for conservation monitoring. A key assumption of automated acoustic monitoring of
Authors
Abraham L. Borker, Matthew W. McKown, Joshua T. Ackerman, Collin A. Eagles-Smith, Bernie R. Tershy, Donald A. Croll

Soil compaction vulnerability at Organ Pipe Cactus National Monument, Arizona

Compaction vulnerability of different types of soils by hikers and vehicles is poorly known, particularly for soils of arid and semiarid regions. Engineering analyses have long shown that poorly sorted soils (for example, sandy loams) compact to high densities, whereas well-sorted soils (for example, eolian sand) do not compact, and high gravel content may reduce compaction. Organ Pipe Cactus Nati
Authors
Robert H. Webb, Kenneth E. Nussear, Shinji Carmichael, Todd C. Esque