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The three principal New Madrid mainshocks of 1811-1812 were followed by extensive aftershock sequences that included numerous felt events. Although no instrumental data are available for either the mainshocks or the aftershocks, available historical accounts do provide information that can be used to estimate magnitudes and locations for the large...

The Broad-winged Hawk (Buteo platypterus) breeds in eastern and central Canada and the United States, and winters in Central America and northern and central South America. Birders and ornithologists count migrating Broad-winged Hawks at dozens of traditional watch sites throughout the northeastern United States. We modeled counts of migrating...

The fragmentation of North American forests by agriculture and other human activities may negatively impact the demographic processes of birds through increases in nest predation and brood parasitism. In fact, the effects of fragmentation on demographic processes are thought to be a major underlying cause of long-term population declines of...

Leveling surveys of a 193‐km circuit across Medicine Lake volcano (MLV) in 1954 and 1989 show that the summit area subsided by as much as 302 ± 30 mm (−8.6 ± 0.9 mm/yr) with respect to a datum point near Bartle, California, 40 km to the southwest. This result corrects...

Exploration ventures in frontier areas have high risks. Before committing to them, firms prepare regional resource assessments to evaluate the potential payoffs. With no historical basis for directly estimating size distribution of undiscovered accumulations, reservoir attribute probability distributions can be assessed subjectively and used to project...

Calving caribou (Rangifer tarandus) of the Central Arctic herd, Alaska, have avoided the infrastructure associated with the complex of petroleum development areas from Prudhoe Bay to Kuparuk (Cameron et al. 1992, Nellemann and Cameron 1998, and Section 4 of this document). Calving females of the Porcupine caribou herd may similarly...

Crater Lake was surveyed nearly to its shoreline by high-resolution multibeam echo sounding in order to define its geologic history and provide an accurate base map for research and monitoring surveys. The bathymetry and acoustic backscatter reveal the character of landforms and lead to a chronology for the concurrent filling...

Sea otters are the only fully marine otter. They share a common ancestry with the Old World land otters, but their route of dispersal to the New World is uncertain. The historic range of the species is along the northern Pacific Ocean rim, between central Baja California and the islands...

Polar bears (Ursus maritimus) of the southern Beaufort Sea population, distributed from approximately Icy Cape, west of Point Barrow, to Pearce Point, east of Paulatuk in Canada, are harvested by hunters from both countries. In Canada, quotas to control polar bear hunting have been in place, with periodic modifications, since...

Since the Twelfth Working Meeting of the IUCN/SSC Polar Bear Specialist Group in 1997, a number of changes in the management of polar bears have occurred in Alaska. On October 16, 2000, the governments of the United States and the Russian Federation signed the “Agreement on the Conservation and Management...

The relationships between wetland water conditions and breeding numbers of Mallard (Anas platyrhynchos), Northern Pintail (A. acuta), Blue-winged Teal (A. discors), and Northern Shoveler (A. clypeata) during May of 1992-1995, were examined on twelve study areas in the eastern Prairie Pothole Region. Data were collected on...

From the mid-1970s through the mid-1980s, use of calving and summer habitats by Central Arctic herd caribou (Rangifer tarandus granti) declined near petroleum development infrastructure on Alaska's arctic coastal plain (Cameron et al. 1979; Cameron and Whitten 1980, Smith and Cameron 1983. Whitten and Cameron 1983a, 1985: Dau and Cameron...

Various aspects of population structure and dynamics of Eleutherodactylus coqui in two forest reserves (Maricao and Guilarte) of the central mountain range of Puerto Rico were determined between July 1997 and June 1998. Adult density ranged from 8–25 animals/100 m2 for the wet season and 3–19 animals/100 m2 for the dry season. Abundance...

Coalbed gas from Middle Pennsylvanian rocks in eastern Kansas is an emerging new energy play. Many of the critical geological parameters that will prove to be the major controls on the production fairways of this potential new resource have yet to be determined. Nevertheless, preliminary analyses indicate that recent leasing...

The composite Boulder batholith, Montana, hosts a variety of mineral deposit types, including important silver-rich polymetallic quartz vein districts in the northern part of the batholith and the giant Butte porphyry copper-molybdenum pre-Main Stage system and crosscutting copper-rich Main Stage vein system in the southern part of the batholith. Previous...

Hafnium isotopic compositions have been determined on a suite of calc-alkaline and high-alumina-olivine tholeiitic lavas from the Lassen region of California and are used, in conjunction with previously published mineralogical, geochemical, and isotopic data, to constrain their petrogenesis. Positive correlation between εHf values and geochemical indices of the modern subduction component...

Research from several regions of the world provides spatially anecdotal evidence to hypothesize which hydrologic and agricultural factors contribute to groundwater vulnerability to nitrate contamination. Analysis of nationally consistent measurements from the U.S. Geological Survey's NAWOA program confirms these hypotheses for a substantial range of agricultural systems. Shallow unconfined aquifers...

The Permian Phosphoria Formation, a petroleum source rock and world-class phosphate deposit, was deposited in an epicratonic successor basin on the western margin of North America. We calculate the seawater circulation in the basin during deposition of the lower ore zone in the Meade Peak Member from the accumulation rates...

We present a new set of contour maps of the seismic structure of North America and the surrounding ocean basins. These maps include the crustal thickness, whole-crustal average P-wave and S-wave velocity, and seismic velocity of the uppermost mantle, that is, Pn and Sn. We found the following: (1) The average thickness...

A sensitive high resolution ion microprobe (SHRIMP) was used in combination with backscattered electron (BSE) and cathodoluminescence (CL) images to determine the age of detrital zircons from sandstones in the Neoproterozoic Middle Run Formation of the eastern Midwest, United States. Eleven samples from seven drill cores of the upper part...

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...

The cause of deeply penetrating ulcers of Atlantic menhaden Brevoortia tyrannus has been the subject of significant research efforts in recent years. These lesions and the associated syndrome termed ulcerative mycosis have been observed along the East Coast of the United States since at least the early 1980s. Although Aphanomyces spp. were isolated from...

Pastures provide substantial habitat for grassland birds of management concern in the Driftless Area of southwestern Wisconsin. The rolling topography in this region is characterized by lowland valleys surrounded by relatively steep and often wooded slopes which are set apart from more expansive treeless uplands. We hypothesized that there would...

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....

Zircon and monazite U-Pb geochronology of rocks in the western Mojave province of the southwest US reveals that the Proterozoic arc exposed there shares an intrusive and deformational history with rocks exposed further east in the Yavapai and Mazatzal belts after approximately 1780 Ma. Consequently, it seems likely that the...