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We determined the effects of a commonly used mosquito (Culicidae) larvicide (California Golden Bear Oil??, also GB-1111) on body mass and survival of mallard (Anas platyrhynchos) ducklings and on target and nontarget invertebrates. Field studies conducted on natural ponds located in salt marshes in south San Francisco Bay indicated that...

We present structural and stratigraphic evidence from a paleoseismic site near Wrightwood, California, for 14 large earthquakes that occurred on the southern San Andreas fault during the past 1500 years. In a network of 38 trenches and creek-bank exposures, we have exposed a composite section of interbedded debris flow deposits...

* What is a Bryophyte? * Bryophytes are the small green plants commonly known as mosses, liverworts and hornworts. Compared to plants, they have primitive tissues for conducting food and water, and they lack a protective outer surface to maintain water balance. Most bryophytes, because they lack tissues such as roots,...

The Hayward fault, a major branch of the right-lateral San Andreas fault system, traverses the densely populated eastern San Francisco Bay region, California. We conducted a paleoseismic investigation to better understand the Hayward fault's past earthquake behavior. The site is near the south end of Tyson's Lagoon, a sag pond...

Paleoseismic investigations across the Mission Creek strand of the San Andreas fault at Thousand Palms Oasis indicate that four and probably five surface-rupturing earthquakes occurred during the past 1200 years. Calendar age estimates for these earthquakes are based on a chronological model that incorporates radiocarbon dates from 18 in situ burn layers...

The expansion of urbanization introduces air pollution to wildlife areas. Some metal contaminants occurring in concentrations too small to have any measurable impact on adult birds may seriously affect embryos that are more sensitive to contaminants than the adult. Chromium, manganese, and lead are toxic and can be passed from...

Sublethal burdens of lead impair behaviors critical to survival in a variety of animals. In a test arena, I measured refuge-seeking behaviors of adult, male, lined shore crabs from lead-free and lead-contaminated sites. The body sizes of the test groups did not differ although the mean total body lead burdens...

Lead pellets from a skeet range impart Pb to the local soil, plants, and animals. Concentrations and distributions of Pb in the various media were studied at the now-abandoned skeet range bordering a cordgrass marsh at the Naval Weapons Station Seal Beach in Southern California. The concentrations of Pb in...

This study examined furcula (wishbone) shape relative to flight requirements. The furculae from 53 museum specimens in eight orders were measured: 1) three-dimensional shape (SR) as indicated by the ratio of the direct distance between the synostosis interclavicularis and the ligamentous attachment of one of its clavicles to the actual...

Located in the Woodville Karst Plain stretching south from Tallahassee to the Gulf of Mexico, Florida's Wakulla Springs is one of the largest and deepest freshwater Springs in the world. It is also a gateway into one of the longest underwater cave system in the United States, a system that...

Information on the rates of land-use and land-cover change is important in addressing issues ranging from the health of aquatic resources to climate change. Unfortunately, there is a paucity of information on land-use and land-cover change except at very local levels. We describe a strategy for estimating land-cover change across...

Blood films from 46 fish crows (Corvus ossifragus Wilson) and 42 American crows (Corvus brachyrhynchos Brehm) from Florida, U.S.A., were examined for blood parasites. Haemoproteus picae Coatney and Roudabush, Haemoproteus danilewskii Kruse, Trypanosoma avium (Danilewsky), and microfilariae of an unidentified filarioid were identified from both species of crows. An unidentified species of Haemoproteus and <span...

We used a supplemental-feeding experiment, the doubly labeled water technique, and a model-selection approach based upon the Akaike Information Criterion to examine effects of food availability on energy expenditure rates of Black-legged Kittiwakes (Rissa tridactyla) raising young. Energy expenditure rates of supplementally fed females (n = 14) and males (n...

We constructed alternative spatial models at two scales to predict Brown-headed Cowbird (Molothrus ater) parasitism rates from land cover maps. The local-scale models tested competing hypotheses about the relationship between cowbird parasitism and distance of host nests from a forest edge (forest-nonforest boundary). The landscape models tested competing hypotheses about...

The introduction and extensive expansion of WNV in the US in the last three years is having a dramatic impact on native wildlife. The disease continues to cause significant mortality in a variety of bird species throughout the eastern US, particularly in American crow and blue jay populations. As the...

Invertebrates are important food sources for lesser prairie-chicken (Tympanuchus pallidicinctus) adults and broods. We compared invertebrate biomass in areas used and not used by lesser prairie-chicken adults and broods. We used radiotelemetry to determine use and non-use areas in sand sagebrush (Artemisia filifolia) prairie in southwestern Kansas and sampled invertebrate...

We here report 359 species in 103 genera from Yellowstone National Park. We found 71.3% of the total number of species in Picea engelmannii forests and 57.4% of the total number in Pseudotsuga menziesii stands. This compares to 42.3% of the species in Pinus contorta and 37.0% of the species...

Foraging intensity and faecal inputs are important determinants of plant community response to herbivory. We used captive adult lesser snow geese (Anser caerulescens caerulescens), which feed on both above- and below-ground plant tissues, to manipulate foraging intensity and faecal inputs to plots in a sedge meadow in spring, 1996. We...

Floristic quality assessment is potentially an important tool for conservation efforts in the northern Great Plains of North America, but it has received little rigorous evaluation. Floristic quality assessments rely on coefficients assigned to each plant species of a region’s flora based on the conservatism of each species relative to...

Information on the habitat requirements and effects of habitat management on wetland birds were summarized from information in more than 500 published and unpublished papers. A range map is provided to indicate the relative densities of the species in North America, based on Breeding Bird Survey (BBS) data. Although the...

Interest by land-management and regulatory agencies in using biological indicators to detect wetland degradation, coupled with ongoing use of this approach to assess water quality in streams, led to the desire to develop and evaluate an Index of Biotic Integrity (IBI) for wetlands that could be used to categorize the...

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Review of: Epiphytic lichen diversity and its dependence on chemical site factors in differently elevated dieback-affected spruce stands of the Harz Mountains. (Dissertationes Botanicae, Band 354). Volker Hesse. 2002. 191 pages, 66 figures, 49 tables, 23x14cm, 390 g. ISBN 978-3-443-64266-2....

Applications of transport time scales are pervasive in biological, hydrologic, and geochemical studies yet these times scales are not consistently defined and applied with rigor in the literature. We compare three transport time scales (flushing time, age, and residence time) commonly used to measure the retention of water or scalar...