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USGS2016

Cooperative Fish and Wildlife Research Units Program—2015 Year In Review

Summary The Cooperative Fish and Wildlife Research Unit (CRU) Program had its 80th anniversary in 2015. We did not have a party, but those of us who work directly for the Unit program on a daily basis celebrate the privilege we feel in being part of one of the greatest conservation institutions in history. Our mission is our hallmark: meeting the actionable science needs of our cooperators, providing them technical guidance and assistance in interpreting and applying new advances in science, and developing the future workforce through graduate education and mentoring. Our success in accomplishing our mission is due principally to the caliber of the scientists and students they recruit, and the tremendous support from our cooperators. The National Cooperators Coalition has been active in fostering support and I am very excited about their energy. A Special Session at the 2015 North American Wildlife and Natural Resources Conference was dedicated to the Unit program, and a vision for our future was presented at this most prestigious conservation policy forum. We compiled a directory of expertise within the Unit program organized within thematic science areas as identified by our cooperators. We intend for this directory to facilitate our transboundary initiatives where two or more Units in collaboration will be the catalyst that binds agencies and organizations together on landscape scale conservation science. We are co-sponsoring a workshop at the 2016 North American conference, along with the Association of Fish and Wildlife Agencies, the American Fisheries Society, and The Wildlife Society to jump-start a dialogue on and identify issues associated with the widening gap between science and management. The CRU is viewed by our cooperators as being the standard for delivering actionable science in conservation, and the exception to the emerging trend. This is testament to the legacy of the Unit Program and the foundation it is built upon. In this Year in Review report, you will find details on staffing, vacancies, research funding, and other pertinent information. You will also see snapshots of Unit projects with information on how results have been or are being applied by cooperators. That is the essence of what we do: science that matter.

Circular↗

USGS1986

Archaeology and public perception of a trans-scientific problem; disposal of toxic wastes in the unsaturated zone

Predicting the effects of toxic-waste disposal on the environment over periods of millenia to hundreds of millenia is a transscientific problem; that is, one not fully addressed by quantitative scientific and engineering endeavors. Archaeology is a pertinent adjunct to such predictions in several ways. First, and foremost, archaeological records demonstrate that delicate, as well as durable, objects buried in thick unsaturated zones of arid and semiarid environments may survive intact for millenia to tens of millenia. This successful preservation of Late Paleolithic to Iron Age artifacts provides independent support for the tentative favorable conclusions of earth scientists regarding the general utility of thick unsaturated zones for toxic-waste isolation. By analogy with the archaeological record, solidified toxic wastes of low solubility that are buried in arid unsaturated zones should remain isolated from the environment indefinitely; modern man presumably should be able to improve upon the techniques used by his ancestors to isolate and preserve their sacred and utilitarian objects. Second, archaeological evidence pertinent to the fate of objects buried in unsaturated zones-although qualitative in nature and subject to the limitations of arguments by analogy-is meaningful to the public and to the courts who, with some scientists and engineers, are reluctant to rely exclusively on computer-generated predictions of the effects of buried toxic wastes on the environment. Third, the archaeological record issues a warning that our descendants may intrude into our waste disposal sites and that we must therefore take special measures to minimize such entry and, if it occurs, to warn of the dangers by a variety of symbols. And fourth, archaeology provides a record of durable natural and manmade materials that may prove to be suitable for encapsulation of our wastes and from which we can construct warning markers that will last for millenia. For these four reasons, archaeologists must join with earth scientists, and other scientists and engineers, in addressing the likely fate of solidfied toxic wastes buried in the thick (200-600 m) unsaturated zones of arid and semiarid regions. Indeed, the input of archaeology might be crucial to public acceptance of even the most carefully chosen and technically sound waste repository.

Circular↗

USGS1954

Southern California Water Bulletin for 1953: General review of the water resources of Southern California for the water year of 1952-53 with special reference to the surface runoff for the water year of 1951-52

This WATER BULLETTIN is one of a series issued annually since June 1944. Its main purpose is to present a brief analysis of those phases of the local water supply associated with the work of the Geological Survey. The first part of this review deals with the water resources for the water year ending September 30, 1953. It contains a brief analysis of the annual precipitation, the provisional runoff at a few stations, the changes in water reserves both in surface reservoirs and underground, and the imported waters. It concludes by pointing out the deficiences in the local water reserves. This bulletin has been prepared by the Surface Water Branch; the section on ground-water conditions was prepared chiefly from information supplied by the Ground Hater Branch.

California↗

USGS2007

Antarctica: A Keystone in a Changing World--Online Proceedings for the Tenth International Symposium on Antarctic Earth Sciences. Santa Barbara, California, U.S.A.--August 26 to September 1, 2007

Overview: The International Symposium on Antarctic Earth Sciences (ISAES) is held once every four years to provide an international forum for presenting research results and new ideas and for planning future Antarctic geoscience research projects. This Tenth ISAES coincides with the International Polar Year (IPY; 50th Anniversary of the International Geophysical Year) and has been structured to showcase the great breadth of geoscience research being done in Antarctic regions by more than more than 100 institutions located in over 30 countries. The science program of the Symposium encompasses six broad themes that cover key topics on evolution and interactions of the geosphere, cryosphere and biosphere and their cross-linkages with past and historic paleoclimates. Emphasis is also on deciphering the climate records in ice cores, geologic cores, rock outcrops and those inferred from climate models. New technologies for the coming decades of geoscience data collection are also highlighted. Ten keynote presentations at the symposium outline the foundation for the research sessions of the symposium and the structure of the Online Proceedings and Proceedings Book for the Tenth ISAES. The ISAES is traditionally a cornerstone meeting for the Scientific Committee on Antarctic Research (SCAR). In recognition of the Tenth ISAES being held in the U.S. for the first time in 30 years and during IPY, the publication of the symposium proceedings is being handled as a special collaborative effort of the U.S. National Science Foundation, the U.S. Geological Survey, The National Academies Polar Research Board and The National Academies Press. The National Academies Polar Research Board oversees the activities of SCAR in the U.S. Special attention has been directed at publication formats for the symposium, to expedite the open and wide sharing of mature and preliminary research results presented in talks and posters at the Tenth ISAES. All symposium presentations are documented by a short Summary printed in the Symposium Program Booklet and either a short research paper or an extended abstract. The research papers and extended abstracts are compiled in this Online Proceedings and are replicated on a DVD-ROM that is placed in the back of the Tenth ISAES Proceedings Book. The Proceedings Book has printed versions of the keynote talks and an overview paper of the symposium. The short research papers and extended abstracts have been handled differently. Research papers present mature research results and syntheses. They have been peer-reviewed using standard journal procedures. Following revisions and acceptances by co-editors, the papers have been formatted for publication and proofread by authors. Each paper has been assigned a Digital Object Identification (DOI) number and separate html link, and posted online (as part of this USGS Open-File Report series) to ensure open and wide access to the research results. Extended abstracts focus on preliminary research results and have not been peer reviewed. They have had only minimal editorial review and revision. Authors have formatted and proofread their papers. Extended abstracts were not given DOI numbers and are included together in a separate chapter of this online Proceedings. USGS publications staff and Stanford-student editorial assistants indexed and compiled the PDF versions of the short research papers and extended abstracts for inclusion in this online Proceedings. USGS staff created the master DVD-ROM that contains a replica of the Online Proceedings for the Tenth ISAES, and provided the DVD-ROM copies that are included in the Tenth ISAES Proceedings Book published by The National Academies Press in the U.S. A team of more than 25 co-editors coordinated with the numerous authors and peer reviewers in handling the many research papers and extended abstracts that are included herein. Handling the large volume of short papers and extended abstracts, getting most of them onli

Open-File Report↗

USGS2004

An Inventory of Aquatic Macroinvertebrates and Calculation of Selected Biotic Indices for the U.S. Army Atterbury Reserve Forces Training Area near Edinburgh, Indiana, September 2000 - August 2002

An investigation was conducted to establish an inventory of aquatic macroinvertebrates in the streams at the U.S. Army Atterbury Reserve Forces Training Area near Edinburgh, Indiana. The data used to develop this inventory were collected during two sampling efforts in September 2000 and July and August 2002. The inventory identified 173 distinct taxa within the study-area streams. Although no rare or endangered species were found, one identified species, Cordulegaster maculata Selys (a twin-spotted spiketail dragonfly), is recognized by the Indiana Department of Natural Resources as being rare enough to warrant special concern. Biotic indices (indicators of water-quality conditions) were calculated from the macroinvertebrate data. Ephemeroptera, Plecoptera, Trichoptera Richness Index values calculated for 23 samples collected from 16 sites ranged from 5 to 15, with more than 75 percent of the values falling within the range of 7 to 11. Hilsenhoff Biotic Index scores and Invertebrate Community Index scores calculated for samples collected at three sites indicate that water quality at these sites ranged from good to poor. The one site with a poor water-quality index score had a small drainage area. The small drainage area and dry conditions during the sampling period may have contributed to the poor scores calculated for this site.

Indiana↗

USGS2015

Dam removal, connectivity, and aquatic resources in the St. Regis River Watershed, New York

The decommissioning and planned removal of the Hogansburg Dam on the St. Regis River in New York has stimulated interest in the potential effects of that barrier removal on the St. Regis watershed. There will be immediate and systemic effects of the Hogansburg Dam removal, which may include inundation of habitats below the dam or dewatering of habitats above the dam, possibly affecting local fish assemblages and (or) local native mussel assemblages; and expansion of stream network connectivity, which has the potential to open a large area of the watershed to migratory aquatic species. Information was collected about biota, water quality, sediment distribution, riverbed dimensions in the vicinity of the dam, and habitat characteristics of headwater sample sites. Complete fish assemblages were collected, but species of special concern associated with the connectivity changes included, American Eel, Atlantic Salmon, Brook Trout, Eastern Sand Darter, and Lake Sturgeon. Freshwater mussels in the vicinity of the dam also were examined and may be at risk of exposure (without a rescue plan) after dam removal. Reservoir sediment will be transported downstream and will alter aquatic habitat as it moves through the system. The dam removal will open more than 440 kilometers of stream habitat to migratory species, allowing them to more easily complete their life cycles. Fish assemblages above the dam may be altered by migrating fishes, but resident Brook Trout are not expected to be adversely affected.

New York↗

USGS2018

A review of literature for gray and harbor seals

Climate change is impacting marine species, causing shifts in occurrence, distribution, and phenology, which can ultimately effect ecosystem structure and functioning (Parmesan & Yohe 2003; Burrows et al. 2011). The study of the timing of recurring biological events throughout an organism’s life is known as phenology (Parmesan & Yohe 2003). The way organisms respond to climate change through altered timing offers insight into their sensitivity and adaptability (Parmesan & Yohe 2003). To gain an understanding of pinniped vulnerability to climate change, specifically through changes in phenology, a comprehensive literature search was conducted using several online databases (e.g., Web of Science, Google Scholar and PubMed). Combinations of relevant terms were searched in order to find studies pertaining to the life history of two regionally important pinniped species: the gray seal (Halichoerus grypus) and the harbor seal (Phoca vitulina). Although special attention was given to studies conducted in the Northwestern Atlantic region, publications giving information on populations in other parts of the world provided important proxy information. Keyword searches were conducted in Web of Science and Google Scholar and represent the published literature through 2017. The remainder of the publications found were cited in the literature returned from the two searches. This document provides an annotated bibliography organized by species (gray and harbor seals) and region, with topical sections for important attributes (e.g. foraging). The focus of this search was for the Gulf of Maine region, but other relevant information yielded by the literature search is presented in order of approximate distance from the focal area.

Report↗

USGS1996

Water quality of the lower Columbia River Basin: Analysis of current and historical water-quality data through 1994

The lower Columbia River Basin includes the river basins draining into the Columbia River below Bonneville Dam—the largest of which is the Willamette River. This report presents the results of a study by the U.S. Geological Survey, done in cooperation with the Lower Columbia River Bi-State Water- Quality Program, to describe the water-quality conditions in the lower Columbia River Basin by interpreting historical data collected and data collected in 1994. Historical water-quality data spanning more than 50 years and comprising more than 200 parameters were collated for interpretation in this report. The U.S. Geological Survey, the Oregon Department of Environmental Quality, and the Washington Department of Ecology collected water-quality data at 10 sites in the lower Columbia River Basin from January to December of 1994. Water-quality constituents measured in 1994 were screened against U.S. Environmental Protection Agency (EPA) and State guidelines. Arsenic, a human carcinogen, was detected in 15 of 16 samples in the lower Columbia River, but was not detected in any of the sampled tributaries. All 15 arsenic detections had concentrations that exceeded both the EPA ambient water-quality criteria for the protection of human health and the EPA human-health advisories for drinking water. Chromium was detected at all four Columbia River sites—most frequently in the Columbia River at Hayden Island. None of the chromium concentrations detected, however, exceeded water-quality criteria or guidelines. Measurements of suspended trace-element concentrations (trace-element concentrations associated with the suspended-sediment fraction) showed that the suspended form is the dominant transport phase for aluminum, iron, and manganese, whereas the dissolved form is the dominant transport phase for arsenic, barium, chromium, and copper. On the basis of tributary loads during summer low-flow months, sources of suspended silver, nickel, aluminum, and antimony exist in the lower Columbia River Basin, whereas the sources of suspended zinc and arsenic exist outside of the lower basin. Twenty organic compounds were detected of the 47 compounds analyzed for this study. None of the organic compounds measured exceeded EPA’s ambient water-quality criteria or drinking-water guidelines. The Willamette River at Portland had the largest number of detections, and all 20 compounds were detected at one time or another at that site. The largest concentrations of the agricultural pesticides, atrazine, metolachlor, and simazine were detected in the Willamette River, where they were detected in 93, 86, 93 percent, respectively, of the samples collected. The highest concentrations of atrazine in the Willamette River were associated with the spring application and fall runoff periods. Both historical and current data showed that the highest water temperatures in the lower Columbia River Basin are present during August. For water years 1977–81 in the Columbia River at Bradwood (river mile 38.9), 75 percent of the daily mean water temperatures during August exceeded 20 degrees Celsius, a “special condition” criterion for the State of Washington. The special condition criterion was exceeded at four sites on the lower Columbia River during July and August, 1994—a period coinciding with season-high air temperatures and low streamflow. Trend tests using data from 1974 to 1994 showed significant (r < 0.05) upward trends for water temperature at the Columbia River at Warrendale and the Willamette River at Portland. Concentrations of dissolved oxygen and total dissolved gas were above saturation levels during high stormflows in the lower Columbia River and the Willamette River during 1994. The high concentrations of total dissolved gas in the Columbia River exceeded Oregon and Washington State standards of 110 percent of saturation and were caused by spilling water at the Columbia River dams. Aquatic life in the lower Columbia River Basin was not subjected to low dissolved-oxygen concentrations. Comparison of dissolved-oxygen concentrations in the Willamette River from 1949–58 to 1972–94 showed a significant increase in dissolved-oxygen concentrations during the low-streamflow months of summer. Trend tests showed significant (r < 0.05) downward trends from 1973 to 1994 for three constituents at the Columbia River at Warrendale: phosphorus in unfiltered water, total dissolved solids, and specific conductance. These trends may be a consequence of more conservative agricultural practices in the area upstream from Warrendale.

Oregon↗

USGS2006

Narrow-headed garter snake (Thamnophis rufipunctatus)

The narrow-headed garter snake is a harmless, nonvenomous snake that is distinguished by its elongated, triangular-shaped head and the red or dark spots on its olive to tan body. Today, the narrow-headed garter snake is a species of special concern in the United States because of its decline over much of its historic range. Arizona's Oak Creek has historically contained the largest population of narrow-headed garter snakes in the United States. The U.S. Geological Survey (USGS) and the Arizona Game and Fish Department jointly funded research by USGS scientists in Oak Creek to shed light on the factors causing declining population numbers. The research resulted in better understanding of the snake's habitat needs, winter and summer range, and dietary habits. Based on the research findings, the U.S. Forest Service has developed recommendations that visitors and local residents can adopt to help slow the decline of the narrow-headed garter snake in Oak Creek.

Fact Sheet↗

USGS2006

Georgia's Stream-Water-Quality Monitoring Network, 2006

The USGS stream-water-quality monitoring network for Georgia is an aggregation of smaller networks and individual monitoring stations that have been established in cooperation with Federal, State, and local agencies. These networks collectively provide data from 130 sites, 62 of which are monitored continuously in real time using specialized equipment that transmits these data via satellite to a centralized location for processing and storage. These data are made available on the Web in near real time at http://waterdata.usgs.gov/ga/nwis/ Ninety-eight stations are sampled periodically for a more extensive suite of chemical and biological constituents that require laboratory analysis. Both the continuous and the periodic water-quality data are archived and maintained in the USGS National Water Information System and are available to cooperators, water-resource managers, and the public. The map at right shows the USGS stream-water-quality monitoring network for Georgia and major watersheds. The network represents an aggregation of smaller networks and individual monitoring stations that collectively provide data from 130 sites.

Georgia↗

USGS1978

Ponding-test procedure for assessing the infiltration capacity of storm-water basins, Nassau County, New York

A procedure to obtain field data for assessing performance of storm-water basins having high infiltration rates is described. The basin selected is divided into test plots, and treated municipal water from a fire hydrant is ponded to the desired depth so that infiltration rates and flow patterns in the unsaturated zone can be determined by standard methods. The study was made at a storm-water basin excavated in glacial outwash deposits in Nassau County, Long Island, N.Y. in 1971-72. The types of interpretations and evaluations that can be made from test data are described, and applications of the procedure as well as guidelines for developing a similar testing program are given. Observations of special significance were: (1) Infiltration rate of the basin at low water stage is about 1.5 feet per hour but increases with increased water level; (2) flow through the unsaturated zone is essentially vertical; (3) infiltration rate is controlled by a surface stratum --in this case a gravelly, sandy loam; and (4) the position of the water table has little effect on infiltration rate provided it is below the lower boundary of the controlling zone. These observations can be used in evaluating a storm-water basin's suitability for supplemental recharge with treated wastewater, in comparing procedures for increasing a basin's infiltration capacity, or in the design of new storm-water basin systems.

Water Supply Paper↗

USGS2015

GIS-Based Identification of Areas with Mineral Resource Potential for Six Selected Deposit Groups, Bureau of Land Management Central Yukon Planning Area, Alaska

This study, covering the Bureau of Land Management (BLM) Central Yukon Planning Area (CYPA), Alaska, was prepared to aid BLM mineral resource management planning. Estimated mineral resource potential and certainty are mapped for six selected mineral deposit groups: (1) rare earth element (REE) deposits associated with peralkaline to carbonatitic intrusive igneous rocks, (2) placer and paleoplacer gold, (3) platinum group element (PGE) deposits associated with mafic and ultramafic intrusive igneous rocks, (4) carbonate-hosted copper deposits, (5) sandstone uranium deposits, and (6) tin-tungsten-molybdenum-fluorspar deposits associated with specialized granites. These six deposit groups include most of the strategic and critical elements of greatest interest in current exploration. This study has used a data-driven, geographic information system (GIS)-based method for evaluating the mineral resource potential across the large region of the CYPA. This method systematically and simultaneously analyzes geoscience data from multiple geospatially referenced datasets and uses individual subwatersheds (12-digit hydrologic unit codes or HUCs) as the spatial unit of classification. The final map output indicates an estimated potential (high, medium, low) for a given mineral deposit group and indicates the certainty (high, medium, low) of that estimate for any given subwatershed (HUC). Accompanying tables describe the data layers used in each analysis, the values assigned for specific analysis parameters, and the relative weighting of each data layer that contributes to the estimated potential and certainty determinations. Core datasets used include the U.S. Geological Survey (USGS) Alaska Geochemical Database (AGDB2), the Alaska Division of Geologic and Geophysical Surveys Web-based geochemical database, data from an anticipated USGS geologic map of Alaska, and the USGS Alaska Resource Data File. Map plates accompanying this report illustrate the mineral prospectivity for the six deposit groups across the CYPA and estimates of mineral resource potential. There are numerous areas, some of them large, rated with high potential for one or more of the selected deposit groups within the CYPA.

Alaska↗

USGS1923

The occurrence of ground water in the United States, with a discussion of principles

The writer has planned and partly prepared a series of six papers on ground water in the United States. These papers are to deal with (1) occurrence, (2) origin, discharge, and quantity, (3) movement and head, (4) quality, (5) recovery and use, and (6) ground-water provinces. The present paper is the first of the series. The writer is indebted to many colaborers for assistance in preparing this paper, especially to the following members of the United States Geological Survey: M. R. Campbell, who read the entire paper; E. W. Shaw, C. E. Van Orstrand, A. F. Melcher, and C. K. Wentworth, who examined Chapter I; W. C. Alden, who examined Chapters II and IV with special reference to their statements regarding glacial geology; E. S. Larsen, who examined a part of Chapter II; G. W. Stosfi, who examined Chapter III; T. W. Stanton, who examined Chapter IV; L. W. Stephenson, who examined the parts of Chapter IV that relate to the Coastal Plain; C. W. Cooke, who furnished many unpublished data on the geology of the Coastal Plain; Miss M. G. Wilmarth, who gave valuable help in compiling the geologic sections; D. G. Thompson and Miss Norah E. Dowell, who furnished original data on the mechanical composition and porosity of various sedimentary materials; B. H. Lane, who made valuable criticisms of the text; and Martin Solem, who had charge of the preparation of the illustrations.

Water Supply Paper↗

USGS2014

Arthropod community structure on bark of koa ( Acacia koa ) and ʻōhiʻā ( Metrosideros polymorpha ) at Hakalau Forest National Wildlife Refuge, Hawaiʻi Island, Hawaiʻi

The arthropod community associated with tree bark contains a wide variety of taxa but is poorly described, particularly in Hawaiʽi. Our overall goals were to evaluate the abundance of arthropods available to foraging birds and how variation in bark substrates may contribute to arthropod distributions in native forests. Our study aimed to identify this fauna on the dominant canopy-forming trees koa ( Acacia koa ) and ʽōhiʽa ( Metrosideros polymorpha ) within wet montane forest at Hakalau Forest National Wildlife Refuge, Hawaiʽi Island. At two sites roughly similar in elevation and habitat structure, we deployed three trap types designed to intercept arthropods moving along bark within tree canopies: a bole trap based on a pre-existing design and two traps specially designed for this study. Bole traps were placed on koa and ʽōhiʽa while branch traps were established on large and small branches of ʽōhiʽa. In total, 15 arthropod orders were identified, with Collembola most abundant (number/trap-day) generally followed by Isopoda and Araneae. Differences in abundance were found in some instances, but overall, few differences were detected between tree species or sites. Relative abundances of arthropod groups were also generally similar between trees and sites and among different parts of ʽōhiʽa. These results indicate that bark-dwelling arthropod communities are similar on koa and ʽōhiʽa, and birds should not develop strong preferences for gleaning arthropods from the bark of either species of tree based on prey availability.

Hawai'i↗

USGS2006

Metallogeny of the Great Basin: Crustal evolution, fluid flow, and ore deposits

The Great Basin physiographic province in the Western United States contains a diverse assortment of world-class ore deposits. It currently (2006) is the world’s second leading producer of gold, contains large silver and base metal (Cu, Zn, Pb, Mo, W) deposits, a variety of other important metallic (Fe, Ni, Be, REE’s, Hg, PGE) and industrial mineral (diatomite, barite, perlite, kaolinite, gallium) resources, as well as petroleum and geothermal energy resources. Ore deposits are most numerous and largest in size in linear mineral belts with complex geology. U.S. Geological Survey (USGS) scientists are in the final year of a research project initiated in the fall of 2001 to increase understanding of relations between crustal evolution, fluid flow, and ore deposits in the Great Basin. Because of its substantial past and current mineral production, this region has been the focus of numerous investigations over the past century and is the site of ongoing research by industry, academia, and state agencies. A variety of geoinformatic tools was used to organize, reinterpret, and display, in space and time, the large amounts of geologic, geophysical, geochemical, and hydrologic information deemed pertinent to this problem. This information, in combination with concentrated research on (1) critical aspects of the geologic history, (2) an area in northern Nevada that encompasses the major mineral belts, and (3) important mining districts and deposits, is producing new insights about the interplay between key tectonic events, hydrothermal fluid flow, and ore genesis in mineral belts. The results suggest that the Archean to Holocene history of the Great Basin was punctuated by several tectonic events that caused fluids of different origins (sea water, basinal brine, meteoric water, metamorphic water, magmatic water) to move through the crust. Basement faults reactivated during these events localized deformation, sedimentation, magmatism, and hydrothermal fluid flow in overlying rocks to form mineral belts that contain ore deposits of different types and ages that are locally superimposed (demonstrating inheritance). Fluid flow in these systems also was influenced by the distribution of permeable lithologies and paleotopographic highs and lows. Hydrothermal fluids evolved from their initial chemistries towards compositions that reflect the ƒ O 2 and ƒ S 2 buffering capacity of, and the ligands and metals present in, the rocks (±older mineralization) through which they moved. In northern Nevada, where gold deposits are relatively common, carbonaceous, pyritic strata buffered fluids of diverse origins to H 2 S-rich compositions so they could transport gold repeatedly over Paleozoic-Cenozoic time (convergent evolution). Ore formed where metal-laden fluids encountered effective physicochemical traps. Maps of Neogene basin fill and erosion surfaces identify areas where preexisting ore deposits have been progressively exposed or concealed. Comparisons with analogous terrains and deposit types in other parts of the world provide global context. The initial findings and some of the databases, geologic maps, sections, reconstructions, hydrogeologic models, topical syntheses, regional overviews, short courses, field guides, and deposit comparisons produced by project staff and associated managers, contractors, and collaborators have been presented in numerous abstracts, symposia, USGS publications, and professional journals over the last 5 years (see the extensive bibliography). Notable among these was the 2005 Geological Society of Nevada symposium in Reno, Nevada, and the 2005 Geological Society of America annual meeting in Salt Lake City, Utah, where project results were presented to audiences from around the nation and world. The final results of the project will be submitted for publication in 2007 to appropriate USGS and professional journals. A special issue of GEOSPHERE, scheduled for publication in 2007, will be devoted to the results of this project and related work. This special issue will reach an international audience and be available worldwide on the internet. Much of the research for this project has concentrated on areas that will receive the focused attention of the mining industry in the future. As such, the data and interpretations generated by this project have direct use for land-use managers in Federal, State, and local agencies. Improved hydrogeologic models developed by this project will considerably enhance ongoing and future water resource investigations in the region. The increased understanding of when, where, and how hydrothermal systems produce significant economic deposits has direct uses for mineral exploration and for future USGS mineral resource assessments in the Great Basin and other parts of the world.

Great Basin↗

USGS1985

Mineral potential of felsic plutonic rocks in the north-central Arabian Shield, Kingdom of Saudi Arabia

Fourteen plutons of Late Proterozoie age potentially favorable for rare-element mineralization have been identified in a geochemical and petrographic assessment of felsic plutonic rocks in the north-central Arabian Shield (lat 23°00'-25°00' N., long 40°00'-45°00' E.). The plutons are highly fractionated, leucocratic granitoids assigned to a major magmatic pulse that spanned the later stages of the Hijaz orogeny (about 610 Ma to about 550 Ma). Most of the targeted plutons are small or not deeply eroded. Two rock types are dominant: subsolvus, muscovite-bearing monzogranite or syenogranite; and hypersolvus, mieroeline perthite granite commonly containing sodic pyriboles. Enrichment in varied suites of the granitophile elements (Sn-W-NbTa-Zr-Y-Th-U) is characteristic. The plutons occupy the central part of a broad arcuate belt of geochemically specialized plutons that conforms generally to the eastern limit of exposed Proterozoic basement. The muscovite-bearing monzogranites containing anomalous tin and tungsten in rock and (or) wadi sediment samples occur generally east of long 42°30' E. Two of these, Jabal Minya and Jabal Khinzir, are recommended for immediate follow-up studies. Of the alkali granites, most of which occur in the area west of long 42°30' E., the composite plutons of Jabal Hadb ad Dayahin and Jabal Tuqfah have the highest potential for rare-element mineralization and warrant prompt systematic investigation. Evaluation of isolated one- or two-element anomalies should be coordinated with current high-density geochemical prospecting programs of the Riofinex Geological Mission.

Open-File Report↗

USGS2022

Standard operating protocol for mark and recapture monitoring of Brook Floater in streams

The Brook Floater ( Alasmidonta varicosa ) is a small (<100 mm) freshwater mussel (Family: Unionidae) found in streams of the eastern United States (U.S.) (Nedeau 2008). While there has been limited effort to document the status of Brook Floater across its range, there is evidence of Brook Floater range contraction and declining local abundances over recent decades (Wicklow et al. 2017, NatureServe 2021). Brook Floater is a Species of Greatest Conservation Need (SGCN) in 15 states (94% of range); listed as endangered, threatened, or special concern in nearly every state and province where it still occurs; and has been extirpated from two states (Rhode Island and Delaware). Brook Floater was petitioned for Federal listing under the U.S. Endangered Species Act; however, the listing was determined not to be warranted (U.S. FWS 2019), although it remains a Regional SGCN of very high concern in U.S. Fish & Wildlife Service (U.S. FWS) Regions 5 (Terwilliger 2015) and 4 (SEAFWA-WDC 2019) and is an At-Risk Species in U.S. FWS Region 5. A critical component of understanding population declines is site-specific information about population density and demographics (e.g., growth, age structure) to assess population viability. This information had previously only been collected for a few populations of Brook Floater (e.g., Massachusetts Division of Fisheries & Wildlife, North Carolina Wildlife Resources Commission) and methods to collect these data varied from state to state, thus limiting comparisons across the range. In 2016, a competitive State Wildlife Grant (SWG) was awarded to develop a standardized monitoring technique that will aid in understanding differences in population viability across its range and assess changes in populations through time. The protocol described in this report was subsequently developed and tested by Massachusetts and Maine (2 sites in each state) and revised based on field experiences. Data collected using this protocol will allow for state managers to make informed decisions about management actions for Brook Floater. Monitoring approaches are ideally designed to meet management objectives. Management objectives are specific, quantifiable outcomes that reflect the values of the decision makers and relate directly to the management decisions (Conroy and Peterson 2013). Lack of well-defined objectives hinders success of conservation and management actions because there are undefined metrics to determine when the objectives have been met (Yoccoz et al. 2001, Nichols and Thompson 2006). While monitoring to understand a system (i.e., status and trends; Reynolds et al. 2016) provides baseline information for developing management recommendations in the future, Nichols and Thompson (2006) criticize status and trends monitoring because of time lags associated with conservation and the costs and resource availability needed for surveillance, among other reasons. State partners in the Brook Floater SWG have a variety of different monitoring objectives (e.g., abundance/density, survival, recruitment) that depend on the population sizes and demographics. There are many approaches for estimating population parameters such as density, age structure, recruitment, and growth rates. For example, presence/absence (i.e., multistate models), counts (i.e., multi-state models or Dail-Madsen model; Dail and Madsen 2011), and capture mark-recapture (CMR; e.g. Cormack-Jolly-Seber models; Lindberg and Rexstad 2002) are all approaches for assessing population status and viability.

Cooperator Science Series↗

USGS2002

Loss of sagebrush ecosystems and declining bird populations in the Intermountain West: Priority research issues and information needs

Sagebrush lands in the Intermountain West are declining rapidly in quality and extent. Consequently, populations of many bird species dependent on these ecosystems also are declining. The greater sage-grouse has been petitioned for listing as a threatened and endangered species, and other species of sagebrush-obligate birds have special conservation status in most states. We identified the primary issues and information needs during a multi-agency workshop, conducted in response to concerns by management agencies related to declining bird population trends in sagebrush habitats. Priority needs were to (1) obtain a better understanding of bird response to habitat and landscape features, (2) develop monitoring designs to sample habitats and bird populations, (3) determine the effects of land use on sagebrush habitats and dependent bird species, and (4) identify linkages between breeding and wintering ranges. This agenda will identify causes and mechanisms of population declines in birds dependent on sagebrush ecosystems and will lead to better management of the ecosystems upon which they depend.

Fact Sheet↗