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: 3743
Killer whale predation on sea otters linking oceanic and nearshore ecosystems Killer whale predation on sea otters linking oceanic and nearshore ecosystems
After nearly a century of recovery from overhunting, sea otter populations are in abrupt decline over large areas of western Alaska. Increased killer whale predation is the likely cause of these declines. Elevated sea urchin density and the consequent deforestation of kelp beds in the nearshore community demonstrate that the otter's keystone role has been reduced or eliminated. This...
Authors
J. A. Estes, M. T. Tinker, T. M. Williams, D.F. Doak
Dietary protein and chlorogenic acid effect on baculoviral disease of noctuid (Lepidoptera: noctuidae) larvae Dietary protein and chlorogenic acid effect on baculoviral disease of noctuid (Lepidoptera: noctuidae) larvae
Insecticidal pathogens such as baculoviruses are currently under intensive development as biorational agents for the control of lepidopteran pests. However, because the efficacy of these orally infective viruses is influenced by host diet, our ability to use baculoviruses effectively in an integrated pest management program requires understanding the influence of dietary components on...
Authors
Kelli Hoover, Susan A. Alaniz, Julie L. Yee, David M. Rocke, Bruce Hammock, Sean Duffey
Smoke-induced seed germination in California chaparral Smoke-induced seed germination in California chaparral
The California chaparral community has a rich flora of species with different mechanisms for cuing germination to postfire conditions. Heat shock triggers germination of certain species but has no stimulatory effect on a great many other postfire species that are chemically stimulated by combustion products. Previous reports have shown that charred wood will induce germination, and here...
Authors
Jon E. Keeley, C. J. Fotheringham
Attacks on sea otters by killer whales Attacks on sea otters by killer whales
Few references to attacks on sea otters, Enhydra lutris, by killer whales, Orcinus orca, exist in the literature. In an extensive review of predatory and non-predatory interactions between killer whales and other marine mammals, Jefferson et al. (1991) cited only one reference (Nikolaev 1965) in which killer whales aggressively pursued sea otters. In another review of attacks on marine...
Authors
Brian B. Hatfield, Dennis Marks, M. Tim Tinker, Kellie Nolan, Joshua Peirce
C4 photosynthetic modifications in the evolutionary transition from land to water in aquatic grasses C4 photosynthetic modifications in the evolutionary transition from land to water in aquatic grasses
Cladistic analysis supports the conclusion that the Orcuttieae tribe of C4 grasses reflect evolution from a terrestrial ancestry into seasonal pools. All nine species in the tribe exhibit adaptations to the aquatic environment, evident in the structural characteristics of the juvenile foliage, which persist submerged for 1–3 months prior to metamorphosis to the terrestrial foliage...
Authors
Jon E. Keeley
Human influences on trophic cascades along rocky shores Human influences on trophic cascades along rocky shores
A three-trophic-level interaction among American Black Oystercatchers (Haematopus bachmani), limpets (Lottia spp.), and erect fleshy algae in rocky intertidal communities of central and southern California was documented via manipulative and “natural” experiments. Removal of the territorial limpet (Lottia gigantea) initially caused large increases in the percent cover of erect fleshy...
Authors
D. R. Lindberg, James A. Estes, Kenneth I. Warheit
Diel acid fluctuations in C4 amphibious grasses Diel acid fluctuations in C4 amphibious grasses
Orcuttieae is a small tribe of C4 grasses endemic to seasonal pools in the southwestern U.S., comprising the basal genus Neostapfia, Tuctoria, and the most derived group, Orcuttia. Growth is initiated underwater, and when pools dry, species undergo a metamorphosis replacing aquatic foliage with terrestrial foliage. O. californica and O. viscida exhibit CAM-like diel fluctuations in...
Authors
Jon E. Keeley
Study design and interpretation of mammalian carnivore density estimates Study design and interpretation of mammalian carnivore density estimates
Ecological theory and wildlife management often depend on reliable comparison and interpretation of population density estimates. A synthesis of 1,772 mammalian carnivore population estimates (713 unique to reference, species, site, and size of study area) from 74 species revealed global patterns among aspects of study and interpretive design that undermine the reliability and usefulness...
Authors
K.S. Smallwood, C. Schonewald
Use of restored riparian habitat by the endangered least Bell's vireo (Vireo bellii pusillus) Use of restored riparian habitat by the endangered least Bell's vireo (Vireo bellii pusillus)
A primary objective of riparian restoration in California is the creation of habitat for endangered species. Four restoration sites in San Diego County were monitored between 1989 and 1993 and evaluated for their suitability as nesting habitat for Vireo bellii pusillus (Least Bell's Vireo), a state and federally endangered obligate riparian breeder. Vegetation structure at each site was...
Authors
B.E. Kus
Efforts to monitor and protect tidewater gobies at Gaviota Creek during a stream bank stabilization project Efforts to monitor and protect tidewater gobies at Gaviota Creek during a stream bank stabilization project
No abstract available at this time
Authors
K. D. Lafferty
Metal and trace element burdens in two shorebird species at two sympatric wintering sites in southern California Metal and trace element burdens in two shorebird species at two sympatric wintering sites in southern California
In January and November, 1994, ten willets (Catoptrophorus semipalmatus) and ten black-bellied plovers (Pluvialis squatarola) were collected at a south-facing sandy beach at the North Island Naval Air Station (NASNI) and ten willets and three plovers were collected at the Tijuana Slough National Wildlife Refuge (TSNWR), 16 km to the southeast. Concentrations of 19 inorganic analytes were
Authors
Clifford A. Hui