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Seven modulators of mammalian monooxygenase activity were screened for their ability to selectively stimulate or inhibit in vitro monooxygenase activities of hepatic microsomes from mallard ducklings treated with phenobarbital, β-naphthoflavone, 3,3′,4,4′,5-pentachlorobiphenyl or vehicle. Microsomes were assayed fluorometrically for four monooxygenases: benzyloxy-, ethoxy-, methoxy-, and pentoxyresorufin-O-dealkylase, in combination with each of...

Snail Kites (Rostrhamus sociabilis) in Florida were monitored between 1969 and 1994 using a quasi-systematic annual survey. We analyzed data from the annual Snail Kite survey using a generalized linear model where counts were regarded as overdispersed Poisson random variables. This approach allowed us to investigate covariates that might have...

We estimated annual survival of Snail Kites (Rostrhamus sociabilis) in Florida using the Kaplan-Meier estimator with data from 271 radio-tagged birds over a three-year period and capture-recapture (resighting) models with data from 1,319 banded birds over a six-year period. We tested the hypothesis that survival differed among three age classes...

The Christmas Bird Count (CBC) is a valuable source of information about midwinter populations of birds in the continental U.S. and Canada. Analysis of CBC data is complicated by substantial variation among sites and years in effort expended in counting; this feature of the CBC is common to many other...

The sensitivity of the tropics to climate change, particularly the amplitude of glacial-to-interglacial changes in sea surface temperature (SST), is one of the great controversies in paleoclimatology. Here we reassess faunal estimates of ice age SSTs, focusing on the problem of no-analog planktonic foraminiferal assemblages in the equatorial oceans that...

The freshwater marshes of the tidal Patuxent River are well known for their annual fall concentration of migrant soras (Porzana carolina) and were formerly the most famous rail hunting grounds in the Chesapeake Bay region. Because of concern over the apparent long-term decline in number of soras and the decline...

We measured the vocal responses and movements of radio-tagged black rails (Laterallus jamaicensis) (n = 43, 26 males, 17 females) to playback of vocalizations at 2 sites in Florida during the breeding seasons of 1992-95. We used regression coefficients from logistic regression equations to model the probability of a...

Estimates of annual survival rates of neotropical birds have proven controversial. Traditionally, tropical birds were thought to have high survival rates for their size, but analyses of a multispecies assemblage from Panama by Karr et al. (1990) provided a counterexample to that view. One criticism of that study has...

To characterize risk, it is necessary to quantify the linkages and interactions between chemical, physical and biological stressors and endpoints in the conceptual framework for ecological risk assessment (ERA). This can present challenges in a multiple stressor analysis, and it will not always be possible to...

The North American Breeding Bird Survey (BBS) was started in 1966, and provides information on population change and distribution for most of the birds in North America. The geographic extent of the survey, and the logistical compromises needed to survey such a large area, present many challenges for estimation...

Count survey data are commonly used for estimating temporal and spatial patterns of population change. Since count surveys are not censuses, counts can be influenced by 'nuisance factors' related to the probability of detecting animals but unrelated to the actual population size. The effects of systematic changes in...

A regional frequency analysis was conducted to estimate the depth-duration frequency of precipitation for 12 durations in Oklahoma (15, 30, and 60 minutes; 1, 2, 3, 6, 12, and 24 hours; and 1, 3, and 7 days). Seven selected frequencies, expressed as recurrence intervals, were investigated (2, 5, 10, 25,...

The U.S. Air Defense Artillery Center and Fort Bliss Municipal Solid Waste Landfill Facility (MSWLF) is located about 10 miles northeast of downtown El Paso, Texas. The landfill is built on the Hueco Bolson, a deposit that yields water to five public-supply wells within 1.1 miles of the landfill boundary...

The White River Basin drains 11,349 square miles of central and southern Indiana and is one of 59 Study Units selected for water-quality assessment as part of the U.S. Geological Survey's National WaterQuality Assessment Program. Defining the environmental setting of the basin and identifying the natural factors and human influences...

The Digital Mapping Techniques '99 (DMT'99) workshop was attended by 91 technical experts from 42 agencies, universities, and private companies, including representatives from 30 state geological surveys (see Appendix A). This workshop was similar in nature to the first two meetings, held in June, 1997, in Lawrence, Kansas (Soller, 1997), and...

Magnetotelluric data delineate distinct layers and lateral variations above the pre-Tertiary basement. On Pahute Mesa, three resistivity layers associated with the volcanic rocks are defined: a moderately resistive surface layer, an underlying conductive layer, and a deep resistive layer. Considerable geologic information can be derived from the conductive layer which...

Understanding patterns of historical erosion and deposition in San Francisco Bay is crucial in managing such issues as locating deposits of sediment-associated contaminants, and the restoration of wetland areas. These problems were addressed by quantitatively examining historical hydrographic surveys. The data from five hydrographic surveys, made from 1867 to 1990,...

Two glaciodeltaic outwash terraces in southern Rensselaer and northern Columbia Counties, known locally as the Schodack and Kinderhook terraces, consist of ice-contact and outwash sand and gravel and together form a regional, unconfined, stratified-drift aquifer with a combined area of 18.75 square miles. The hydrogeology of these aquifers is summarized...

Yucca Mountain, in southern Nevada, is being investigated by the U.S. Department of Energy as a potential site for a repository for high-level radioactive waste. This report documents the results of surface-based geologic, pneumatic, hydrologic, and geochemical studies conducted during 1992 to 1996 by the U.S. Geological Survey in the...

The maps presented in this report (depth to Coastal Plain unconformity, Quaternary sediment thickness, paleochannel thickness, and modern sand thickness) are helpful for determining sand-resource availability for beach nourishment programs and understanding the influence that the inner-shelf framework of southern Long Island has on coastal processes and evolution. The maps...

The confined aquifers of the New Jersey Coastal Plain are sands that range in thickness from 50 to 600 feet and are separated by confining units. The confining units are composed of silts and clays that range in thickness from 500 to 1,000 feet. The aquifers are recharged by precipitation...

The alluvial aquifer near Carrollton, Kentucky, lies in a valley eroded by glacial meltwater that was later part filled with outwash sand and gravel deposits. The aquifer is unconfined, and ground water flows from the adjacent bedrock-valley wall toward the Ohio River and ground-water withdrawal wells. Ground-water-level and Ohio River...

PHREEQC version 2 is a computer program written in the C programming language that is designed to perform a wide variety of low-temperature aqueous geochemical calculations. PHREEQC is based on an ion-association aqueous model and has capabilities for (1) speciation and saturation-index calculations; (2) batch-reaction and one-dimensional (1D) transport calculations...

The lower Boise River, between Lucky Peak Dam and the mouth of the river near Parma, Idaho, is adversely affected by various land- and water-use activities. To assess the biotic integrity of the river and the effects of environmental perturbations on aquatic community structure, and to provide a baseline from...

The computer program WTAQ calculates hydraulic-head drawdowns in a confined or water-table aquifer that result from pumping at a well of finite or infinitesimal diameter. The program is based on an analytical model of axial-symmetric ground-water flow in a homogeneous and anisotropic aquifer. The program allows for well-bore storage and...