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The U.S. Geological Survey has been a provider of remotely sensed information for decades. As the availability and use of satellite data has grown, USGS has placed increasing emphasis on expanding the knowledge about the science of remote sensing and on making remotely sensed data more accessible. USGS encourages widespread...

Accurate measurement of coral reef community metabolism is a necessity for process monitoring and in situ experimentation on coral reef health. Traditional methodologies used for these measurements are effective but limited by location and scale constraints. We present field trial results for a new benthic chamber system called the Submersible...

Old-growth forests of Engelmann spruce (Picea engelmannii Parry ex. Engelm.) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) dominate much of the landscape of the Rocky Mountains. We characterized the structure, biomass and production of 18 old-growth (200-450-year-old) spruce/fir forests in Rocky Mountain National Park, Colorado, as well as the stand-level...

Submarine-flank deposits of Hawaiian volcanoes are widely recognized to have formed largely by gravitationally driven volcano spreading and associated landsliding. Observations from submersibles show that prominent benches at middepths on flanks of Mauna Loa and Kilauea consist of volcaniclastic debris derived by landsliding from nearby shallow submarine and subaerial flanks...

Arsenic compounds have been used extensively in agriculture in the US for applications ranging from cotton herbicides to animal feed supplements. Roxarsone (3-nitro-4-hydroxyphenylarsonic acid), in particular, is used widely in poultry production to control coccidial intestinal parasites. It is excreted unchanged in the manure and introduced into the environment when...

Geographical variation of organochlorine pesticides (OCPs) was studied in blood samples from 90 adult female polar bear (Ursus maritimus) from Svalbard, Franz Josef Land, Kara Sea, East-Siberian Sea and Chukchi Sea. In all regions, oxychlordane was the dominant OCP. Regional differences in mean levels of HCB, oxychlordane, trans-nonachlor, ??-HCH, ??-HCH...

In 1999, 1 Gt (1.1 billion st) of coal was produced in the United States. Of this total, 37% was produced in Wyoming, Montana and North Dakota. Coals of Tertiary age from these states typically have low ash contents. Most of these coals have sulfur contents that are in compliance...

We conducted a 30-d manipulative experiment in Valley Creek, Minnesota, to examine interspecific interactions between juvenile brown trout Salmo trutta and adult slimy sculpin Cottus cognatus. We measured the instantaneous growth of each species in the presence and absence of the other in 1-m2 enclosures. We tested single-species (three slimy...

Landsat-7 and Landsat-5 have orbits that are offset from each other by 8 days. During the time that the sensors on both satellites are operational, there is an opportunity for conducting analyses that incorporate multiple intra-annual high spatial resolution data sets for characterizing the Earth's land surface. In the current...

Low salinity plumes of coastal origin are occasionally found far offshore, where they display a distinct color signature detectable by satellites. The impact of such plumes on carbon fixation and phytoplankton community structure in vertical profiles and on basin wide scales is poorly understood. On a research cruise in June 1999, ocean-color satellite-images (Sea-viewing Wide Field-of-view Sensor, SeaWiFS) were used in locating a Mississippi River plume in the eastern Gulf of Mexico. Profiles sampled...

We have constructed a composite image of the fault systems of the M 6.7 San Fernando (1971) and Northridge (1994), California, earthquakes, using industry reflection and oil test well data in the upper few kilometers of the crust, relocated aftershocks in the seismogenic crust, and LARSE II (Los Angeles Region...

We compared 62 specimens, 48-126.5 mm standard length, of Acanthurus bahianus from the northeastern Gulf of Mexico with 95 specimens from other localities to determine if the distinguishing characters in the original description of the Gulf of Mexico endemic surgeonfish Acanthurus randalli were valid. No color pattern or meristic differences were found, and the...

Mixed-species flocks of native and introduced birds were studied for four years in an upper elevation Hawaiian rain forest. Those flocks were characterized by strong seasonality, large size, low species richness, high intraspecific abundance, a lack of migrants, and a general lack of territoriality or any sort of dominance hierarchy....

Computer simulations involving general circulation models, a hydrologic modeling system, and a ground water flow model indicate potential impacts of selected climate change projections on ground water levels in the Lansing, Michigan, area. General circulation models developed by the Canadian Climate Centre and the Hadley Centre generated meteorology estimates for...

I sampled movements and amount of area used by boreal toads (Bufo boreas) between June and October for 3 yr. Females were found farther from the breeding site than were males, and mean home ranges, as calculated by the adaptive kernel method, were four times larger for females than for males. Temperature and snow accumulation were comparable...

Advancements in ancient DNA analyses now permit comparative molecular and morphological studies of extinct animal dung commonly preserved in caves of semiarid regions. These new techniques are showcased using a unique dung deposit preserved in a late glacial vizcacha (Lagidium sp.) midden from a limestone cave in southwestern Argentina (38.5° S)....

Avian fruit consumption may ensure plant reproductive success when frugivores show consistent preference patterns and effectively remove and disperse seeds. In this study we examined avian fruit preferences and their seed-removal services at five study sites in north-central Puerto Rico. At each site, we documented the diet of seven common...

We evaluated the partitioning and toxicity of cadmium (Cd) and copper (Cu) spiked into formulated sediments containing two types of organic matter (OM), i.e., cellulose and humus. Amendments of cellulose up to 12.5% total organic carbon (TOC) did not affect partitioning of Cd or Cu between sediment and pore water...

Low-temperature calcite and opal record the past seepage of water into open fractures and lithophysal cavities in the unsaturated zone at Yucca Mountain, Nevada, site of a proposed high-level radioactive waste repository. Systematic measurements of calcite and opal coatings in the Exploratory Studies Facility (ESF) tunnel at the proposed repository...

We examined whether surgically-implanted radio transmitters with percutaneous antennas affected behavior of Lesser Canada Geese (Branta canadensis parvipes) in Anchorage, Alaska. We implanted either a 26-g VHF radio transmitter or a larger VHF radio that was the same mass (35 g) and shape as a satellite transmitter in the coelom...

The importance of interspecific competition as a mechanism regulating population abundance in offshore marine communities is largely unknown. We evaluated offshore competition between Asian pink salmon and Bristol Bay (Alaska) sockeye salmon, which intermingle in the North Pacific Ocean and Bering Sea, using the unique biennial abundance cycle of Asian...

The southernmost major breeding area of Canvasbacks (Aythya valisineria) is located at the Ruby Lake National Wildlife Refuge, Nevada, in the high desert of the western Great Basin. We determined winter distributions, recovery rates, and survival for Canvasbacks banded in Nevada from March to November, 1968–2000. Winter recovery distributions did...

The reproductive biology of female Dungeness crabs was studied with crab-pot and dive-transect sampling in five bays within or near Glacier Bay National Park and Preserve, southeastern Alaska, in April and September yearly from 1992 to 1998. A large percentage of nonovigerous, mature females was found in April, a time...

Since twice as much C is sequestered in soils as is contained in the atmosphere, the factors controlling the decomposition rate of soil C are important to the assessment of the effects of climatic change. The formation of chemically resistant humic substances might be an important process controlling recycling of CO2 to the atmosphere. Our objectives were to measure the rate of formation and loss of humic substances during...

The United States (U.S.) Climate Division data set is commonly used in applied climatic studies in the United States. The divisional averages are calculated by including all available stations within a division at any given time. The averages are therefore vulnerable to shifts in average station location or elevation over...