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Publications

These publications showcase the significant science conducted in our Science Centers.

Filter Total Items: 16733

The role of ridge subduction in determining the geochemistry and Nd–Sr–Pb isotopic evolution of the Kodiak batholith in southern Alaska The role of ridge subduction in determining the geochemistry and Nd–Sr–Pb isotopic evolution of the Kodiak batholith in southern Alaska

The Paleocene Kodiak batholith, part of the Sanak–Baranof belt of Tertiary near-trench intrusive rocks, forms an elongate body (~ 150 km long) that transects Kodiak Island from SW to NE. The batholith consists of three zones (Southern, Central, and Northern) of kyanite-, muscovite-, and garnet-bearing biotite tonalite and granodiorite and less abundant granite that intruded an...
Authors
Robert A. Ayuso, Peter J. Haeussler, Dwight Bradley, David W. Farris, Nora K. Foley, Gregory A. Wandless

Selected achievements, science directions, and new opportunities for the WEBB small watershed research program Selected achievements, science directions, and new opportunities for the WEBB small watershed research program

Over nearly two decades, the Water, Energy, and Biogeochemical Budgets (WEBB) small watershed research program of the U.S. Geological Survey (USGS) has documented how water and solute fluxes, nutrient, carbon, and mercury dynamics, and weathering and sediment transport respond to natural and humancaused drivers, including climate, climate change, and atmospheric deposition. Together with...
Authors
Pierre D. Glynn, Matthew C. Larsen, Earl A. Greene, Heather L. Buss, David W. Clow, Randall J. Hunt, M. Alisa Mast, Sheila F. Murphy, Norman E. Peters, Stephen D. Sebestyen, James B. Shanley, John F. Walker

Analysis of vegetation changes in Rock Creek Park, 1991-2007 Analysis of vegetation changes in Rock Creek Park, 1991-2007

Vegetation data collected at Rock Creek Park every 4 years during 1991-2007 were analyzed for differences among 3 regions within the park and among years. The variables measured and analyzed were percentage of twigs browsed, percentage of canopy cover, species richness of herbaceous plants, number of tree seedlings in each of 7 height classes, tree seedling stocking rate for low deer...
Authors
Jeff S. Hatfield, Cairn Krafft

Genetic structure in the Anaxyrus boreas species group (anura, Bufonidae): an evaluation of the Southern Rocky Mountain population Genetic structure in the Anaxyrus boreas species group (anura, Bufonidae): an evaluation of the Southern Rocky Mountain population

The Anaxyrus boreas species group is comprised of four species endemic to the western United States: A. boreas, A. canorus, A. exsul, and A. nelsoni. Disjunct populations of the widespread western toad Anaxyrus boreas from Colorado and southern Wyoming, the southern rocky mountain population (SRMP), were previously candidates for listing under the United States Endangered Species Act...
Authors
John F. Switzer, Robin L. Johnson, Barbara A. Lubinski, Tim L. King

Habitat assessment for giant pandas in the Qinling Mountain region of China Habitat assessment for giant pandas in the Qinling Mountain region of China

Because habitat loss and fragmentation threaten giant pandas (Ailuropoda melanoleuca), habitat protection and restoration are important conservation measures for this endangered species. However, distribution and value of potential habitat to giant pandas on a regional scale are not fully known. Therefore, we identified and ranked giant panda habitat in Foping Nature Reserve, Guanyinshan...
Authors
Tian-Tian Feng, Frank T. van Manen, Na-Xun Zhao, Ming Li, Fu-Wen Wei

Trend estimation in populations with imperfect detection Trend estimation in populations with imperfect detection

1. Trends of animal populations are of great interest in ecology but cannot be directly observed owing to imperfect detection. Binomial mixture models use replicated counts to estimate abundance, corrected for detection, in demographically closed populations. Here, we extend these models to open populations and illustrate them using sand lizard Lacerta agilis counts from the national...
Authors
Marc Kery, Robert M. Dorazio, Leo Soldaat, Arco Van Strien, Annie Zuiderwijk, J. Andrew Royle

White-nose Syndrome management: Report on structured decision making initiative White-nose Syndrome management: Report on structured decision making initiative

This report describes an analysis undertaken to assist state and federal natural resources managers in addressing the following question: What management measures should be taken this year within a given area to control the spread and minimize the effects of white-nose syndrome (WNS) on hibernating bats at the individual and population levels? The answer depends upon specific...
Authors
Jennifer A. Szymanski, Michael C. Runge, Mary J. Parkin, Mike Armstrong

Identifying baldcypress-water tupelo regeneration classes in forested wetlands of the Atchafalaya Basin, Louisiana Identifying baldcypress-water tupelo regeneration classes in forested wetlands of the Atchafalaya Basin, Louisiana

Baldcypress-water tupelo (cypress-tupelo) swamps are critically important coastal forested wetlands found throughout the southeastern U.S. The long-term survival and sustainability of these swamp forests is unknown due to large-scale changes in hydrologic regimes that prevent natural regeneration following logging or mortality. We used NWI wetland maps and remotely sensed hydrologic data...
Authors
Stephen P. Faulkner, Prajwol Bhattarai, Yvonne C. Allen, John A. Barras, Glenn C. Constant

Avifauna of the Pongos Basin, Amazonas Department, Peru Avifauna of the Pongos Basin, Amazonas Department, Peru

We provide an inventory of the avifauna of the Pongos Basin, northern Amazonas Department, Peru based on museum specimens collected during expeditions spanning >60 years within the 20th century. Four hundred and thirty-eight species representing 52 families are reported. Differences between lowland and higher elevation avifaunas were apparent. Species accounts with overviews of specimen...
Authors
Daniel M. Brooks, John P. O’Neill, Mercedes S. Foster, Todd Mark, Nico Dauphine, Irma J. Franke

Effect of distance-related heterogeneity on population size estimates from point counts Effect of distance-related heterogeneity on population size estimates from point counts

Point counts are used widely to index bird populations. Variation in the proportion of birds counted is a known source of error, and for robust inference it has been advocated that counts be converted to estimates of absolute population size. We used simulation to assess nine methods for the conduct and analysis of point counts when the data included distance-related heterogeneity of...
Authors
Murray G. Efford, Deanna K. Dawson

A saltwater flotation technique to identify unincubated eggs A saltwater flotation technique to identify unincubated eggs

Field studies on nesting birds sometimes involve questions related to nest initiation dates, length of the incubation period, or changes in parental incubation behavior during various stages of incubation. Some of this information can be best assessed when a nest is discovered before the eggs have undergone any incubation, and this has traditionally been assessed by floating eggs in...
Authors
C.A. Devney, S. L. Kondrad, K.R. Stebbins, K.D. Brittingham, D. J. Hoffman, G. H. Heinz

Dietary toxicity and tissue accumulation of methylmercury in American kestrels Dietary toxicity and tissue accumulation of methylmercury in American kestrels

American kestrels (Falco sparverius) were fed meat diets containing 0, 3, 6, or 12 ppm (dry weight) methylmercury chloride. Birds fed the 12-ppm diet started to show signs of neurotoxicity after 26 days and all died in 39?49 days. One male kestrel fed the 6-ppm diet died after 75 days of exposure and several others showed signs of neurotoxicity after 45 days. None of the birds fed the 3...
Authors
Richard S. Bennett, John B. French, Ronald Rossmann, Romona J. Haebler
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