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Concern for the status of horseshoe crab (Limulus polyphemus) has increased as harvest for conch and eel bait has increased and spawning habitat has decreased. In early 1999 a workshop was held at the behest of the Atlantic States Marine Fisheries Commission to design a statistically valid survey of horseshoe...

For many studies of the population dynamics, growth, and movement of juvenile Atlantic salmon Salmo salar, it is necessary to resample tagged individuals multiple times. However, common sampling techniques such as electrofishing can have negative effects on fish survival and growth, especially when individuals are repeatedly sampled. We describe an alternative...

"Today was another record-breaking day," the evening radio or television declares. High temperatures, low temperatures, floods, drought - take your choice. But how can we put these pronouncements in perspective? What do they really mean?We present two types of information in this article: 1) an analysis of daily air temperature...

More than 5000 km3 of nearly compositionally homogeneous crystal-rich dacite (∼68 wt % SiO2: ∼45% Pl + Kfs + Qtz + Hbl + Bt + Spn + Mag + Ilm + Ap + Zrn + Po) erupted from the Fish Canyon magma body during three phases: (1) the pre-caldera Pagosa Peak...

Isotopes of Be and C were used to reconstruct loess accumulation, hillslope evolution, and agricultural modification in soils of western Iowa. While both elements are derived from additions by the atmosphere (via plants in the case of carbon), the differences in element cycling allow erosional and depositional processes to be...

We measured the daily energy expenditure of free-living Common Loon (Gavia immer) chicks using doubly labeled water (DLW). Average body mass of chicks during the DLW measures were 425, 1,052, and 1,963 g for 10 day-old (n = 5), 21 day-old (n = 6), and 35 day-old (n = 6)...

The ability to predict species occurrences quickly is often crucial for managers and conservation biologists with limited time and funds. We used measured associations with landscape patterns to build accurate predictive habitat models that were quickly and easily applied (i.e., required no additional data collection in the field to make...

Available population and diet data on double-crested cormorant (Phalacrocorax auritus) and smallmouth bass (Micropterus dolomieui) numbers, demographics, and exploitation rates were synthesized to examine the relationship between cormorant and smallmouth bass abundance in the U.S. waters of the eastern basin of Lake Ontario....

We have now entered an era of large-scale attempts to restore ecological functions and biological communities in impaired ecosystems. Our knowledge base of complex ecosystems and interrelated functions is limited, so the outcomes of specific restoration actions are highly uncertain. One approach for exploring that uncertainty and anticipating the range...

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...

The Cretaceous Iles and Williams Fork Formations of the Mesaverde Group contain important reservoir and source rocks for basin-centered gas accumulations in the Piceance Basin of northwestern Colorado. The sandstones in these formations have very low permeability, so low that successful production of gas requires the presence of fractures. To...

By measuring relative earthquake arrival times using waveform cross correlation and locating earthquakes using the double difference technique, we are able to reduce hypocentral errors by 1 to 2 orders of magnitude over routine locations for nearly 8000 events along a 35-km section of the Calaveras Fault. This represents ∼92%...

No abstract available....

Isotopic variations in melting snow are poorly understood. We made weekly measurements at the Central Sierra Snow Laboratory, California, of snow temperature, density, water equivalent and liquid water volume to examine how physical changes within the snowpackgovern meltwater δ18O. Snowpack samples were extracted at 0.1 m intervals from ground level to the top of...

Wildlife biologists and health specialists have been frustrated by a long list of negative findings in their AVM investigations, however studies continue to provide pieces of information to aid the determination of the cause and its source. Available data indicated that AVM may have been present since at least 1990,...

Toxoplasma gondii was found in endemic Hawaiian birds, including 2 nene geese (Nesochen sandvicensis), 1 red-footed booby (Sula sula), and an introduced bird, the Erckels francolin (Francolinus erckelii). All 4 birds died of disseminated toxoplasmosis; the parasite was found in sections of many organs, and the diagnosis was confirmed by immunohistochemical...

A total of 44 amphibian mortality events and 20 morbidity events were reviewed retrospectively. The most common cause of amphibian mortality events was infection by ranaviruses (Family: Iridoviridae). Ranavirus epizootics have abrupt onset and affect late-stage larvae and recent metamorphs. Mortality events due to ranavirus infections affected only widespread and...

Mycoplasmosis is a transmissible upper respiratory tract disease that has affected plans for management and conservation of wild desert and gopher tortoises in the United States. Although impact of mycoplasmosis on populations of desert and gopher tortoises is unknown, increased prevalence of seropositive animals as well as field observations of...

A salient characteristic of river discharge is its temporal variability. The time series of flow at a point on a river can be viewed as the superposition of a smooth seasonal cycle and an irregular, random variation. Viewing the random component in the spectral domain facilitates both its characterization and...

The United States Geological Survey (USGS) was formed in 1879 as the nation's primary natural science and information agency. The mission of the agency is to provide scientific information to a??describe and understand the Earth; minimize loss of life and property from natural disasters; manage water, biological, energy, and mineral...

An important statistical development of the last 30 years has been the advance in regression analysis provided by generalized linear models (GLMs) and generalized additive models (GAMs). Here we introduce a series of papers prepared within the framework of an international workshop entitled: Advances in GLMs/GAMs modeling: from species distribution...

In 1996, the Smithsonian Tropical Research Institute and the Republic of Panama's Environmental Authority, with support from the United States Agency for International Development, undertook a comprehensive program to monitor the ecosystem of the Panama Canal watershed. The goals were to establish baseline indicators for the integrity of forest communities...

The Florida Gap (FI-Gap) project provides an assessment of the degree to which native animal species and natural communities are or are not represented in existing conservation lands. Those species and communities not adequately represented in areas being managed for native species constitute 'gaps' in the existing network of conservation...

A marine sanctuary is an environment where the interests of science and society meet. Land and marine managers need access to the best scientific data available that describe the environment and environmental processes in sanctuaries. The sidescan sonar imagery, bathymetry, sample analyses and other data discussed in the papers in...