Search Results

Stranding networks, in which carcasses are recovered and sent to diagnostic laboratories for necropsy and determination of cause of death, have been developed to monitor the health of marine mammal and bird populations. These programs typically accumulate comprehensive, long-term datasets on causes of death that can be used to identify...

We investigated the utility of a fishery-independent trawl survey for assessing a potential multispecies shark nursery in Georgia's nearshore and inshore waters. A total of 234 subadult sharks from six species were captured during 85 of 216 trawls. Catch rates and size distributions for subadult sharks and the ratio of...

We examined site characteristics and prey abundances where wintering Aythya affinis (Lesser Scaup; hereafter scaup) foraged within three regions of the Indian River Lagoon system in central Florida. We observed that scaup concentrated in the Indian and Banana rivers; however, density of prey items did not differ between foraging sites...

No abstract available....

The concept of learning about natural resources through the practice of management has been around for several decades and by now is associated with the term adaptive management. The objectives of this paper are to offer a framework for adaptive management that includes an operational definition, a description of conditions...

No abstract available...

Reintroduction of endangered Whooping Cranes (Grus americana) in eastern North America has successfully established a migratory population between Wisconsin and Florida. Eighty birds (47 males, 33 females) were released between 2001 and 2006, and all birds were tracked following release with satellite and/or VHF monitoring devices. By the end of...

The US geomagnetism community is supported by NASA, NOAA, USGS, NSF, DOD, and US universities. During the Decade of Geopotential Field Research, inaugurated in 1999 with the launch of the Danish satellite Ørsted on a US rocket, the US community has been involved in satellite mission development and analysis, instrument...

The U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center archives electronic science collections that total over two petabytes in size and over 100,000 rolls of aerial and satellite film. Limited resources, the evolution of missions, and recommendations from advisory committees have led to the development of a...

Sustainable soils are a requirement for maintaining human civilizations (Carter and Dale 1974; Lal 1989). However, as the “most complicated biomaterial on the planet” (Young and Crawford 2004), soils represent...

The ability of an organism to disperse to suitable habitats, especially in modified and fragmented systems, determines individual fitness and overall population viability. The bluehead sucker (Catostomus discobolus), flannelmouth sucker (Catostomus latipinnis), and roundtail chub (Gila robusta) are three species native to the upper Colorado River Basin that now occupy...

Environmental radionuclides—in combination with stable isotopes, geochemistry, and other hydrological techniques—provide a powerful tool, often indispensable, for studying the cycling of water in continental hydrological systems. The use of environmental radionuclides in surface water studies is reviewed in the chapter. The chapter also briefly discusses groundwater and geothermal water taking into consideration the fact...

No abstract available....

Macrolichens collected in Douglas County, Wisconsin in the 1940s, 1970s and 2009 are compared in order to determine floristic changes. Species sensitive to disturbance, land use change, and possibly climate that have changed over these time spans are identified and suggested for further monitoring. The total lichen flora of Douglas...

In the United States, environmentally impaired rivers are subject to regulation under total maximum daily load (TMDL) regulations that specify watershed wide water quality standards. In California, the setting of TMDL standards is accompanied by the development of scientific and management plans directed at achieving specific water quality objectives. The...

I conducted a comparative study of a new jar design (experimental chamber) with a standard egg incubation vessel (McDonald jar). Experimental chambers measured 0.4 m in diameter by 1.3 m in height and had a volume of 200 L. McDonald hatching jars measured 16 cm in diameter by 45 cm...

Miocene flood basalts of the Columbia River Basalt Group inundated eastern Washington, Oregon, and adjacent Idaho between 17 and 6 Ma. Some of the more voluminous flows followed the ancestral Columbia River across the Cascade arc, Puget-Willamette trough, and the Coast Range to the Pacific Ocean. We have used field...

No abstract available....

The lessons learned from CALFED indicate that ingredients important in the long-term resolution of water management issues may not result in short-term “solutions”. The value of this special issue lies in its identification of ingredients that stimulate re-framing of issues, adapting to new knowledge...

Livestock grazing is a common land use across the western United States, but concerns have been raised regarding its potential to affect amphibian populations. We studied the short-term effects of full and partial livestock grazing exclosures on Rana luteiventris (Columbia Spotted Frog) populations using a controlled manipulative field experiment with pre- and...

No abstract available....

No abstract available....

Estuarine food webs are highly variable and complex, making identification of their trophic pathways difficult. Energy for the food web of the San Francisco Estuary is thought to be based largely on in situ phytoplankton production, but little attention has been paid to littoral habitats, where other...

With phase inversion, one can estimate subsurface velocities using the phases of first-arriving waves, which are the frequency-domain equivalents of the traveltimes. Phase inversion is modified to make it suitable for processing traveltimes from near-surface refraction surveys. The modifications include parameterizing the model, correcting the observed phases, and selecting the...

Numerous state and federal agencies are increasingly concerned with the rapid expansion of invasive, noxious weeds across the United States. Herbicides are frequently applied as weed control measures in forest and rangeland ecosystems that frequently overlap with critical habitats of threatened and endangered fish species. However, there is little published...