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At least 829 records · Page 46Linked to original sources

Vascular Plant and Vertebrate Inventory of Saguaro National Park, Tucson Mountain District

This report summarizes the results of the first comprehensive inventory of plants and vertebrates at the Tucson Mountain District (TMD) of Saguaro National Park, Arizona. From 2001 to 2003 we surveyed for vascular plants and vertebrates (amphibians, reptiles, birds, and mammals) at the district to document the presence of species within its boundaries. Park staff also carried out extensive infrared-triggered camera work for medium and large mammals from 2002-2005 and results from that effort are reported here. Our spatial sampling design for all taxa employed a combination of random and nonrandom survey sites. Survey effort was greatest for medium and large mammals and herpetofauna. Because we used repeatable study designs and standardized field methods, these inventories can serve as the first step in a biological monitoring program for the district. We also provide an overview of previous survey efforts in the district. We use data from our inventory and other surveys to compile species lists and to assess inventory completeness. The survey effort for herpetofauna, birds, and medium and large mammals was the most comprehensive ever undertaken in the district. We recorded a total of 320 plant and vertebrate species, including 21 species not previously found in the district (Table 1). Based on a review of our inventory and past research at the district, there have been a total of 723 species of plants and vertebrates found there. We believe inventories for most taxonomic groups are nearly complete. Based on our surveys, we believe the native plant and vertebrate community compositions of the district are relatively intact, though some species loss has occurred and threats are increasing, particularly to herpetofauna and larger mammals. Of particular note is the relatively small number of non-native species and their low abundance in the district, which is in contrast to many nearby natural areas. Rapidly expanding development on the west, north, and east sides of the district is cause for concern that the park continue its commitment to environmental restoration, which is largely responsible for reducing the threats posed by non-native plants. With continued maintenance of natural processes and the ecological structure of the park's biodiversity, the park will become an increasingly important place to both the general public and the scientific community. This report supersedes results reported in Powell et al. (2002, 2003).

Open-File Report↗

Activity center selection by northern spotted owls

The federally threatened northern spotted owl ( Strix occidentalis caurina ) has been intensively studied across its range, and habitat needs for the species have influenced forest management in northwestern North America for decades. Dense forest canopies are often reported in the scientific literature and agency management plans as an important habitat attribute for spotted owls, though the means of measuring forest canopy and interpreting species requirements vary across studies and more importantly, among management plans. We used light detection and ranging (lidar) measurements of canopy cover, canopy surface heterogeneity, and upper canopy surface connectivity, and an index of the presence of a competitive invasive species, the barred owl ( S. varia ), in multinomial discrete choice models using a Bayesian framework to evaluate selection of forest cover types by spotted owls in Oregon, USA, 2008–2015. We designated yearly activity centers based on the most biologically significant observation during the nesting season (Mar–Aug), generally centered on the nest tree. Spotted owls selected activity centers with more canopy cover and higher heterogeneity of the canopy surface within 100 m than was available within their territories. The average proportion of canopy cover within 100 m of a spotted owl activity center was 0.79 ± 0.12 (SD; range = 0.34–0.99). The presence of barred owls did not explain variability in selection of spotted owl activity centers, but barred owls might not affect third‐order habitat selection within territories, or our index was too spatially coarse to detect these effects on spotted owl resource selection. We demonstrate that lidar provides researchers and managers with a tool that can accurately measure forest canopies over large areas, and assist in mapping spotted owl habitat.

Oregon↗

Identifying new invasive plants in the face of climate change: A focus on sleeper species

Sleeper populations are established populations of introduced species whose population growth is limited by one or more abiotic or biotic conditions. Sleeper populations pose an invasion risk if a change in those limiting conditions, such as climate change, enables population growth and invasion. With thousands of established introduced species, it is critical that we identify and prioritize potential sleepers. Here, we identified introduced plants established in the northeastern United States with high impacts and the potential to expand with climate change. Of 1795 introduced plants established in one or more northeastern states, we focused on 118 taxa regulated by one or more states outside the Northeast plus 61 taxa recorded as invasive globally and under consideration for regulation in the Northeast. We used the environmental impact classification for alien taxa framework to quantify negative ecological and socioeconomic impacts reported in the scientific literature for these 169 taxa. We compared mean minimum winter temperature and annual precipitation where the species were abundant with current and future climate in the Northeast to evaluate whether climate change could increase risk. We identified 49 plants with ecological impacts linked to loss of native diversity and 94 plants with socioeconomic impacts. 81 species showed an increase in climatic suitability for abundant populations with climate change. Using ecological impact, increased climate suitability, and presence in fewer than 20 Northeastern counties, we highlight 18 species as high priorities for potential management in the Northeast. This approach can inform climate-smart, proactive management of sleeper populations before they become invasive.

Biological Invasions↗

Social and biological perspectives to investigate and address illegal shooting of raptors

Humans have shot raptors for centuries. However, in many countries these actions have been illegal since the mid-twentieth century. Despite this history, there is not a comprehensive understanding of the characteristics of this activity, its frequency, and why it occurs. We used literature review and principles drawn from ecology, sociology, and criminology to understand this problem. First, we review literature on raptor shooting globally to explore documented motivations for shooting and we describe the history of raptor shooting in the United States of America (USA). Then, to illustrate the contemporary frequency and geographic breadth of the shooting of raptors, we systematically compile records from scientific and media reports from across the USA. Finally, we outline a transdisciplinary framework to meet the challenge of understanding and managing illegal shooting of raptors. Our framework encompasses six best practices: (1) understand the biology of the problem, (2) build professional networks and partnerships, (3) leverage engagement and public support, (4) apply insights from study of human-wildlife interactions, (5) draw lessons from criminology, and (6) use implementation science to evaluate outcomes. We illustrate application of these best practices with a case study from an Illegal Shooting Working Group recently formed in Boise, Idaho, USA. There is growing recognition that illegal shooting of raptors is a pressing conservation challenge. Solving this challenge can be facilitated by inclusion of information from multiple fields of study; the approach we outline provides one potential mechanism to address this issue.

Global Ecology and Conservation↗

Comparative mobility of sulfonamides and bromide tracer in three soils

In animal agriculture, sulfonamides are one of the routinely used groups of antimicrobials for therapeutic and sub-therapeutic purposes. It is observed that, the animals when administered the antimicrobials, often do not completely metabolize them; and excrete the partially metabolized forms into the environment. Due to the continued use of antimicrobials and disposal of untreated waste, widespread occurrence of partially metabolized antimicrobials in aquatic and terrestrial environments has been reported in various scientific journals. In this research, the mobility of two sulfonamides - sulfamethazine (SMN), sulfathiazole (STZ) and a conservative bromide tracer was investigated in three soils collected from regions in the United States with large number of concentrated animal-feed operations. Results of a series of column studies indicate that the mobility of these two sulfonamides was dependent on pH, soil charge density, and contact time. At low pH and high charge density, substantial retention of sulfonamides was observed in all three soils investigated, due to the increased fraction of cationic and neutral forms of the sulfonamides. Conversely, enhanced mobility was observed at high pH, where the sulfonamides are predominantly in the anionic form. The results indicate that when both SMN and STZ are predominantly in anionic forms, their mobility approximates the mobility of a conservative bromide tracer. This observation is consistent for the mobility of both SMN and STZ individually, and also in the presence of several other antimicrobials in all three soils investigated. Higher contact time indicates lower mobility due to increased interaction with soil material.

Journal of Environmental Management↗

Piscicides and invertebrates: after 70 years, does anyone really know?

The piscicides rotenone and antimycin have been used for more than 70 years to manage fish populations by eliminating undesirable fish species. The effects of piscicides on aquatic invertebrate assemblages are considered negligible by some and significant by others. This difference of opinion has created contentious situations and delayed native fish restoration projects. We review the scientific evidence and report that short-term (< 3 months) impacts of piscicides to invertebrate assemblages varied from minor to substantial and long-term (> 1 year) impacts are largely unknown. Recovery of invertebrate assemblages following treatments ranged from a few months for abundances of common taxa to several years for rarer taxa. Variation in reported effects was primarily due to natural variation among species and habitats and a lack of adequate pre- and post-treatment sampling which prevents determining the true impacts to invertebrate assemblages. The factors most likely to influence impacts and recovery of aquatic invertebrate assemblages following piscicide treatments are: (1) concentration, duration, and breadth of the piscicide treatment; (2) invertebrate morphology and life history characteristics, including surface area to volume ratios, type of respiration organs, generation time, and propensity to disperse; (3) refugia presence; and (4) distance from colonization sources.

Fisheries↗

A selected bibliography of remote sensing applications to soil science

The bibliography contains approximately 200 references dealing with the application of remote sensing technology to the identification and analysis of soils. The scientific papers and reports listed describe procedures and methods used in data collection and include specific applications of those data to soil studies. Most citations discuss current work from 1970 to 1978 and all references are categorized according to the type of remotely sensed data used and their application.

Report↗

Abstracts of the 11th Annual U.S. Geological Survey, Central Region, 1999 Poster Review; Collected Abstracts of Selected Poster Papers Presented at Scientific Meetings

In 1999, the U.S. Geological Survey Central Region had a poster review where USGS scientists showcased posters that had been presented at scientific meetings. This report contains abstracts for selected posters that were presented at this review. Science topics were from several USGS teams with a broad range of topics.

Open-File Report↗

The Loma Prieta, California, earthquake of October 17, 1989: Aftershocks and postseismic effects

While the damaging effects of the earthquake represent a significant social setback and economic loss, the geophysical effects have produced a wealth of data that have provided important insights into the structure and mechanics of the San Andreas Fault system. Generally, the period after a large earthquake is vitally important to monitor. During this part of the seismic cycle, the primary fault and the surrounding faults, rock bodies, and crustal fluids rapidly readjust in response to the earthquake's sudden movement. Geophysical measurements made at this time can provide unique information about fundamental properties of the fault zone, including its state of stress and the geometry and frictional/rheological properties of the faults within it. Because postseismic readjustments are rapid compared with corresponding changes occurring in the preseismic period, the amount and rate of information that is available during the postseismic period is relatively high. From a geophysical viewpoint, the occurrence of the Loma Prieta earthquake in a section of the San Andreas fault zone that is surrounded by multiple and extensive geophysical monitoring networks has produced nothing less than a scientific bonanza. The reports assembled in this chapter collectively examine available geophysical observations made before and after the earthquake and model the earthquake's principal postseismic effects. The chapter covers four broad categories of postseismic effect: (1) aftershocks; (2) postseismic fault movements; (3) postseismic surface deformation; and (4) changes in electrical conductivity and crustal fluids.

California↗

Base of the upper layer of the phase-three Elkhorn-Loup groundwater-flow model, north-central Nebraska

The Elkhorn and Loup Rivers in Nebraska provide water for irrigation, recreation, hydropower produc­tion, aquatic life, and municipal water systems for the Omaha and Lincoln metropolitan areas. Groundwater is another important resource in the region and is extracted primarily for agricultural irrigation. Water managers of the area are interested in balancing and sustaining the long-term uses of these essential surface-water and groundwater resources. Thus, a cooperative study was established in 2006 to compile reliable data describing hydrogeologic properties and water-budget components and to improve the understanding of stream-aquifer interactions in the Elkhorn and Loup River Basins. A groundwater-flow model was constructed as part of the first two phases of that study as a tool for under­standing the effect of groundwater pumpage on stream base flow and the effects of management strategies on hydrologically connected groundwater and surface-water supplies. The third phase of the study was implemented to gain additional geologic knowledge and update the ELM with enhanced water-budget information and refined discretization of the model grid and stress periods. As part of that effort, the ELM is being reconstructed to include two vertical model layers, whereas phase-one and phase-two simulations represented the aquifer system using one vertical model layer. This report presents a map of and methods for developing the elevation of the base of the upper model layer for the phase-three ELM. Digital geospatial data of elevation contours and geologic log sites used to esti­mate elevation contours are available as part of this report.

Nebraska↗

Characterization of streamflow, water quality, and instantaneous dissolved solids, selenium, and uranium loads in selected reaches of the Arkansas River, southeastern Colorado, 2009-2010

As a result of continued water-quality concerns in the Arkansas River, including metal contamination from historical mining practices, potential effects associated with storage and movement of water, point- and nonpoint-source contamination, population growth, storm-water flows, and future changes in land and water use, the Arkansas River Basin Regional Resource Planning Group (RRPG) developed a strategy to address these issues. As such, a cooperative strategic approach to address the multiple water-quality concerns within selected reaches of the Arkansas River was developed to (1) identify stream reaches where stream-aquifer interactions have a pronounced effect on water quality and (or) where reactive transport, and physical and (or) chemical alteration of flow during conveyance, is occurring, (2) quantify loading from point sources, and (3) determine source areas and mass loading for selected constituents. (To see the complete abstract, open Report PDF.)

Colorado↗

Hydrologic and hydraulic analyses of Great Meadow wetland, Acadia National Park, Maine

The U.S. Geological Survey completed hydrologic and hydraulic analyses of Cromwell Brook and the Sieur de Monts tributary in Acadia National Park, Maine, to better understand causes of flooding in complex hydrologic and hydraulic environments, like those in the Great Meadow wetland and Sieur de Monts Spring area. Regional regression equations were used to compute peak flows with from 2 to 100-year recurrence intervals at seven locations. Light detection and ranging data were adjusted for bias caused by dense vegetation in the Great Meadow wetland; and then combined with local ground surveys used to define the underwater topography and hydraulic structures in the study area. Hydraulic modeling was used to evaluate flood response in the study area to a variety of hydrologic and hydraulic scenarios. Hydraulic modeling indicates that enlarging the culvert at Park Loop Road could help mitigate flooding near the Sieur de Monts Nature Center that is caused by streamflows with large recurrence intervals; however, hydraulic modeling also indicates that the Park Loop Road culvert does not aggravate flooding near the Nature Center caused by the more frequent high intensity rainstorms. That flooding is likely associated with overland flow resulting from (1) quick runoff from the steep Dorr Mountain hitting the lower gradient Great Meadow wetland area and (2) poor drainage aggravated by beaver dams holding water in the wetland. Rapid geomorphic assessment data collected in June 2015 and again in April 2016 indicate that Cromwell Brook has evidence of aggradation, degradation, and channel widening throughout the drainage basin. Two of five reference cross sections developed for this report also indicate channel aggradation.

Maine↗

Elevated road segment (ERS) passage design may provide enhanced connectivity for amphibians, reptiles, and small mammals

Introduction: Designs for safe and effective road crossing structures for small animals are typically under-road microtunnels and culverts which have varying levels of effectiveness reported in the scientific literature. Many species, particularly migratory amphibians, may have limited ability to find and use passages if they are too far apart, resulting in substantial barrier effects. Methods: We designed a novel open elevated passage (elevated road segment: ERS), similar to a low terrestrial bridge, that could theoretically be built to any length based upon species needs and movement characteristics. A 30 m length prototype ERS was installed along a forest road with a history of amphibian road mortality in Sierra National Forest, Fresno County, CA, USA. From 2018 to 2021, we monitored small animal activity under the ERS in relation to surrounding roadside and forest habitats using active infrared cameras. Results: We documented a total of 8,815 unique use events, using species specific independence criteria, across 22 species of amphibians (3), reptiles (4), and small mammals (15). Poisson regression modeling of taxonomic group activity under the ERS, roadside and forest, showed that amphibian activity was highest in the forest habitat, no differences were observed for reptiles, and small mammal activity was highest under the ERS. However, mean activity estimates under the ERS were equal to or greater than the open roadside habitat for all 22 species, suggesting that adding cover objects, such as downed logs and vegetation may further enhance passage use. Discussion: Overall, results showed that the design of the ERS crossing has potential to provide high connectivity for a wide range of amphibian, reptile, and small mammal species while reducing road mortality. ERS systems can also be used in areas with challenging terrain and other hydrological and environmental constraints. Incorporating current road ecology science, we provide supplemental ERS concept designs for secondary roads, primary roads and highways to help increase the options available for road mitigation planning for small animals.

California↗

Functional traits and ecological affinities of riparian plants along the Colorado River in Grand Canyon

Trait-based approaches to vegetation analyses are becoming more prevalent in studies of riparian vegetation dynamics, including responses to flow regulation, groundwater pumping, and climate change. These analyses require species trait data compiled from the literature and floras or original field measurements. Gathering such data makes trait-based research time intensive at best and impracticable in some cases. To support trait-based analysis of vegetation along the Colorado River through Grand Canyon, a data set of 20 biological traits and ecological affinities for 179 species occurring in that study area was compiled. This diverse flora shares species with many riparian areas in the western USA and includes species that occur across a wide moisture gradient. Data were compiled from published scientific papers, unpublished reports, plant fact sheets, existing trait databases, regional floras, and plant guides. Data for ordinal environmental tolerances were more readily available than were quantitative traits. More publicly available data are needed for traits of both common and rare southwestern U.S. plant species to facilitate comprehensive, trait-based research. The trait data set is free to use and can be downloaded from ScienceBase: https://www.sciencebase.gov/catalog/item/58af41dee4b01ccd54f9f2ff and https://dx.doi.org/10.5066/F7QV3JN1

Arizona↗

Pesticides in surface waters: distribution, trends, and governing factors

Pesticde use in agriculture and non-agriculture settings has increased dramatically over the last several decades. Concern about adverse effects on the environment and human health has spurred an enormous amount of research into their environmental behavior and fate. Pesticides in Surface Waters presents a comprehensive summary of this research. This book evaluates published studies that focus on measuring pesticide concentration. The studies chosen include peer reviewed scientific literature, government reports, laboratory studies, and those using microcosms and artificial streams and ponds. The authors used this information to develop their overview of pesticide contamination of surface waters. The exhaustive compilation of data along with the fundamental science make this book essential for those involved in pesticide use, environmental protection, water quality, and human or ecological risk assessment. Pesticides in Surface Waters covers the results of actual studies, sources of pesticides to surface water, fate and transport, and environmental significance. Hundreds of data-packed tables, maps, charts, and drawings illustrate the key points, making research and application easy and cost effective.

Book↗

Multichannel seismic reflection surveys over the Antarctic continental margin relevant to petroleum resource studies

More than 100,000 km of marine multichannel seismic profiles have been acquired over the continental margin of Antarctica since 1976 by scientific research programs of Australia, Brazil, France, Italy, Japan, Norway, Poland, United Kingdom, United States, U.S.S.R. and West Germany. Although scientific results are reported for most of these data, they also are relevant to petroleum resource assessment. Because of the one or two orders of magnitude greater cost of standard land survey techniques in Antarctica compared with marine techniques in areas of open water, there will likely be no great amount of coverage on the interior of the Antarctic ice sheet. Despite this, several countries are experimenting in a research mode using land systems, and deep crustal reflection sur eys at carefully selected interior sites will probably be made soon.

Book chapter↗

Waterfowl Management Handbook

The North American Waterfowl Management Plan, the Service's most recent mandate for management of migratory waterfowl, and recent legislation such as the Farm Bill all underscore the need for a single source of information about the management of waterfowl and their habitat. Much of this information exists in scientific papers, unpublished reports, or has never been recorded, and thus is not readily accessible by waterfowl managers. A prototype handbook was developed in 1987 and critiqued by 38 reviewers who provided suggestions on style and substance as well as topics for inclusion. The assistance of these reviewers, who included Federal and State wildlife managers, Federal and State biologists, and scientists in the United States and Canada, is most gratefully acknowledged. This product differs from most Fish and Wildlife Leaflets. It will be issued as a series of chapters over the next several years, each with a unique number, designed to be inserted in an accompanying looseleaf binder.

Fish and Wildlife Leaflet↗

Analysis of water quality in the Blue River watershed, Colorado, 1984 through 2007

Water quality of streams, reservoirs, and groundwater in the Blue River watershed in the central Rocky Mountains of Colorado has been affected by local geologic conditions, historical hard-rock metal mining, and recent urban development. With these considerations, the U.S. Geological Survey, in cooperation with the Summit Water Quality Committee, conducted a study to compile historical water-quality data and assess water-quality conditions in the watershed. To assess water-quality conditions, stream data were primarily analyzed from October 1995 through December 2006, groundwater data from May 1996 through September 2004, and reservoir data from May 1984 through November 2007. Stream data for the Snake River, upper Blue River, and Tenmile Creek subwatersheds upstream from Dillon Reservoir and the lower Blue River watershed downstream from Dillon Reservoir were analyzed separately. (The complete abstract is provided in the report)

Colorado↗