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A natural resource condition assessment for Sequoia and Kings Canyon National Parks: Appendix 14: plants of conservation concern

Sequoia and Kings Canyon National Parks are located in the California Floristic Province, which has been named one of world‘s hotspots of endemic biodiversity (Myers et al. 2000). The California Floristic Province is the largest and most important geographic floristic unit in California and extends from the Klamath Mountains of southwestern Oregon to the northwestern portion of Baja California (Hickman 1993). The Sierra Nevada, one of six regions that make up the California Floristic Province, covers nearly 20% of the land in California yet contains over 50% of its flora. Within the Sierra Nevada, the southern Sierra supports more Sierran endemic and rare plant taxa than the central and northern portions of the region (Shevock 1996). Sequoia and Kings Canyon National Parks (SEKI) encompass roughly 20% of the southern Sierra Nevada region. The parks overlap three floristic subregions (central Sierra Nevada High, southern Sierra Nevada High, and southern Sierra Nevada Foothills), and border the Great Basin Floristic Province. The parks support a rich and diverse vascular flora composed of over 1,560 taxa. Of these, 150 taxa are identified as having special status. The term special status is applied here to include taxa that are state or federally listed, rare in California, or at risk because they have a limited distribution. Only one species from these parks is listed under the state or federal Endangered Species Acts ( Carex tompkinsii , Tompkins‘ sedge, is listed as a rare species under the California Endangered Species Act), and one species is under review for federal endangered listing ( Pinus albicaulis , whitebark pine). However, an absence of threatened and endangered species recognized by Endangered Species Acts is not equivalent to an absence of species at risk. There are 83 plant taxa documented as occurring in SEKI that are considered imperiled or vulnerable in the state by the California Department of Fish and Game‘s California Natural Diversity Database (CNDDB 2010a). There are an additional 66 taxa not formally listed by CNDDB that are recognized as having special status because their distribution is restricted to the Sierra Nevada. Special status plants are distributed throughout the two parks and inhabit a wide range of environments along the length of the elevation gradient that characterizes these parks. Ideally, we would assess the condition (status and trends) of each of the taxa on the SEKI special status plant list, documenting current population sizes, demographic rates and demographic trends. We would also hope to quantify the effects of individual stressors on each species based on existing monitoring and research. However, no data are available for most of the species on the special status plant list. For those few species (12 herbaceous species and two tree species) for which we possess some change over time information, the data are not adequate to make a competent assessment. Note that we have not explored the tree demographic information in any detail, as is covered in the NRCA Intact Forest/Five Needle Pines and Sequoia chapters. In general, we are unable to present an ‗integrity‘ metric for special status species in the parks, since the data to quantify the condition of each species in such a manner is not available. In contrast, the park does possess substantial data describing biodiversity in the parks. Therefore, our analysis focuses on describing the distribution and rarity of special status plants within the parks, with a particular focus on assessing the spatial distribution of species richness. We hope that such information will prove useful to park managers in determining which areas in the parks merit the most attention (for example in developing monitoring protocols). We also assess potential vulnerability of special status species to the stressors chosen by the NRCA working group, using both park data and available literature. As a first step, we spent considerable effort updating and refining the criteria for the special status plant list, as this list defines which taxa are considered in our assessment. Observation data of these species was then compiled from all known sources in order to provide a comprehensive view of where special status plants have been documented and, ultimately, to enable the most informed determinations of areas in the parks that potentially support the highest number of rare and endemic taxa. These ‗hot spot‘ analyses are presented by geographic region, vegetation type and elevation. For these and other analyses presented in this report, we place more focus on summarizing findings for the herbaceous and shrub special status taxa than on special status trees. The trees which qualify as special status are the focus of other NRCA chapters, including Giant Sequoia and Intact Forests/Five-needle Pines. We do, however, present their mapped distributions and provide overviews of research related to the special status tree taxa in the Stressors section of this report.

California↗

Stratigraphic sections of the Phosphoria formation in Idaho

The first of a series of reports giving detailed stratigraphic sections of the Phosphoria formation in the Western phosphate field as measured and described by the Geological Survey will be released as Circulars within the next few months. Because of the needs of industry for many of these data during the 1951 field season, and in view of the unavoidable delays attendant on publication, the tabular data to be included in these Circulars are hereby placed on open file in simple reproduction form (prepared by Ozalid from photographic negatives) and without explanatory text so that immediate use may be made of the data. The tables include data on sections in four states: Montana, Idaho, Wyoming, and Utah; and the tables for each of these states are bound together as individual reports. The tables include name and location of section measured, brief description of geologic setting, acknowledgments for field and analytical work, abstract data on the sections (bed number, rock name, sample number, and thickness), and analytical data on the samples. The analytical data include reports on P 2 O 5 and acid insoluble for all samples and additional analyses, such as Al 2 0 3 , Fe 7 0 3 , loss on ignition, F, and V 2 O 5 , for selected samples. Spectrographic analyses for a large number of elements are included samples from selected localities, and special analyses have been made of a few samples. These reports are placed on open file at the offices of the Geological Survey in Washington, D. C., Spokane, Washington, Salt Lake City, Utah, and Montpelier, Idaho, and at the offices of the Idaho Bureau of Mines and Geology, Moscow, Idaho, the Montana Bureau of Mines and Geology, Butte, Montana, and the Wyoming Geological Survey, Laramie, Wyoming, and the University of Utah, Salt Lake City, Utah.

Idaho↗

Water resources data, Pennsylvania, water year 2003—volume 2. Susquehanna and Potomac River basins

Water resources data for the 2003 water year for Pennsylvania consist of records of discharge and water quality of streams; contents and elevations of lakes and reservoirs; and water levels and water quality of ground-water wells. This report, Volume 2 contains (1) discharge records for 84 continuous-record streamflow-gaging stations, 13 partial- record stations, 21 special study and miscellaneous streamflow sites; (2) elevation, contents, and water-quality records for 12 lakes and reservoirs; (3) water-quality records for 30 gaging stations and 66 ungaged streamsites; (4) water-level records for 39 network observation wells; and (5) water-quality analyses at 35 special study ground-water wells. Site locations are shown in figures throughout the report. Additional water data collected at various sites not involved in the systematic data-collection program are also presented. These data together with the data in Volumes 1 and 3, represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State, local, and Federal agencies in Pennsylvania.

Water Data Report↗

Population ecology of the mallard: IV. A review of duck hunting regulations, activity, and success, with special reference to the mallard

This, the fourth in a series of reports on the mallard, ( Anas platyrhynchos ), deals at length with the harvest of mallards by waterfowl hunters. Long-term summaries of duck hunting regulations (1948- 1974), Migratory Bird Hunting Stamp sales (1934-1974), Hunter Questionnaire (1952-1974), Duck Wing Collection (1960-1974), and Hunter Performance (1965-1972) Survey data for the United States are presented and discussed. Similar data from Canada are also summarized. Mallard harvest figures for 1961-1974 are presented by Mallard Harvest Area, of which 100 are defined for the United States and 14 for Canada, as well as by State or Province and flyway. During the 23-year period beginning in 1952, an average of 1.6 million adult and 0.2 million junior waterfowl hunters accumulated almost 12.3 million hunter-days of recreation and a harvest of 11.2 million ducks each year. Hunter reports indicate that mallards made up about 43% (5.5 million annually) of the ducks taken before 1960, when mallard regulations were less restrictive; the Duck Wing Survey indicates that mallards have made up 33% of the harvest (3.6 million annually) since 1960. The age and sex compositions and the chronological distribution of the mallard harvest are examined in detail. Among the patterns noted are peak harvests during the first few days of the season in many States, alternately increasing and decreasing annual age ratios, and sex ratios that suggest differential migration of adult drakes and hunter selectivity for males. It is estimated that almost 19% of the ducks shot down are not retrieved. Relationships between duck hunting regulations and hunter behavior are examined briefly. Hunter compliance with mallard bag limits, hunter selectivity of mallards by sex, and, to a lesser extent, the size of the unretrieved kill are all sensitive to the particular bag limit regulations in effect. Survey data are also examined for relationships between harvest and various hunting regulations: starting time and day of the week for opening day, opening date, season length, split seasons, daily shooting hours, and daily bag limits. Tables are presented relating changes in duck and mallard harvests to season length and bag limit, and examples of what effects changes in other regulations have on harvest are also given. The evaluation of bag limit regulations, one of the most important tools used in managing harvest, is carried a step further with the development of a procedure for calculating expected hunter success under a wide variety of bag limit regulations. This method appears promising for evaluating point-limit as well as fixed-limit regulations. In addition, it may provide useful measurements of the degree of hunter selectivity induced by various types of bag limit regulations, an increasingly important aspect of harvest management. Finally, this study clearly demonstrates that the effects of a particular regulation can differ dramatically from area to area, so it is usually necessary to evaluate each proposal on a State-by-State basis.

Resource Publication↗

Aquatic organism passage at road-stream crossings—synthesis and guidelines for effectiveness monitoring

Restoration and maintenance of passage for aquatic organisms at road-stream crossings represents a major management priority, involving an investment of hundreds of millions of dollars (for example, U.S. Government Accounting Office, 2001). In recent years, passage at hundreds of crossings has been restored, primarily by replacing barrier road culverts with bridges or stream simulation culverts designed to pass all species and all life stages of aquatic life and simulate natural hydro-geomorphic processes (U.S. Forest Service, 2008). The current situation has motivated two general questions: 1. Are current design standards for stream simulation culverts adequately re-establishing passage for aquatic biota? and 2. How do we monitor and evaluate effectiveness of passage restoration? To address the latter question, a national workshop was held in March 2010, in Portland, Oregon. The workshop included experts on aquatic organism passage from across the nation (see table of participants, APPENDIX) who addressed four classes of methods for monitoring effectiveness of aquatic organism passage—individual movement, occupancy, demography, and genetics. This report has been written, in part, for field biologists who will be undertaking and evaluating the effectiveness of aquatic organism passage restoration projects at road-stream crossings. The report outlines basic methods for evaluating road-stream crossing passage impairment and restoration and discusses under what circumstances and conditions each method will be useful; what questions each method can potentially answer; how to design and implement an evaluation study; and points out the fundamental reality that most evaluation projects will require special funding and partnerships among researchers and resource managers. The report is organized into the following sections, which can be read independently: 1. Historical context: In this section, we provide a brief history of events leading up to the present situation involving aquatic organism passage as a useful context for the issues covered herein. 2. Importance of connectivity for aquatic organisms: In this section, we provide background information regarding the movement characteristics of aquatic organisms and their vulnerability to passage impairment, and the importance of connectivity for a broad diversity of aquatic vertebrates and invertebrates. This section should be useful for practitioners in selecting what species to monitor in relation to aquatic organism passage. 3. Methods for evaluating aquatic organism passage: In this section, we present a range of perspectives on alternatives for assessing and monitoring aquatic organism passage impairment and the effectiveness of passage restoration actions, including the following methods: Individual Movement, Occupancy Models, Abundance (Demography), and Molecular Genetic Markers. 4. Relevance, strengths, and limitations of the four methods: In this section, we discuss the utility of each of the methods as a tool for assessing and quantifying passage impairment and restoration effectiveness. 5. Guidelines for selecting a method: In this section, we review some fundamental criteria and guidelines to consider when selecting a method for monitoring in the context of answering three important questions that should be addressed when developing a plan for evaluating aquatic organism passage. 6. Study and monitoring design considerations: In this section, we discuss four key design elements that need to be considered when developing a monitoring design for assessing passage impairment and restoration. The basic objectives of the report are to: 1. Review the movement characteristics of five groups of aquatic organisms that inhabit streams and to assess their general vulnerability to passage impairment at road-stream crossings; 2. Review four methods for monitoring aquatic organism passage impairment and the effectiveness of actions to restore passage at road-stream crossing structures; 3. Assess the relevance, strengths, and limitations of each method as a monitoring tool; 4. Identify and discuss guidelines that will be useful for selecting a monitoring method; and 5. Discuss what we have identified as the four key elements that need to be considered when developing a monitoring design for assessing passage impairment and restoration at road-stream crossings.

Open-File Report↗

Stratigraphic sections of the Phosphoria formation in Utah

The first of a series of reports giving detailed stratigraphic sections of the Phosphoria formation in the Western phosphate field as measured and described by the Geological Survey will be released as Circulars within the next few months. Because of the needs of industry for many of these data during the 1951 field season, and in view of the unavoidable delays attendant on publication: the tabular data to be included in these Circulars are hereby placed on open file in simple reproduction form (prepared by Ozalid from photographic negatives) and without explanatory text so that immediate use may be made of the data. The tables include data on sections in four states: Montana, Idaho, Wyoming, and Utah; and the tables for each of these states are bound together as individual reports. The tables include name and location of section measured, brief description of geologic setting, acknowledgments for field and analytical work, abstract data on the sections (bed number, rock name, sample number, and thickness), and analytical data or the samples. The analytical data include reports on P 2 O 5 and acid insoluble for all samples and additional analyses, such as Al 2 0 3 , Fe 7 0 3 , loss on ignition, F, and V 2 O 5 , for selected samples. Spectrographic analyses for a large number of elements are included for samples from selected localities, and special analyses have been made of a few samples. These reports are placed on open file at the offices of the Geological Survey in Washington, D. C., Spokane, Washington, Salt Lake City, Utah, and Montpelier, Idaho, and at the offices of the Idaho Bureau of Mines and Geology, Moscow, Idaho, the Montana Bureau of Mines and Geology, Butte, Montana, and the Wyoming Geological Survey, Laramie, Wyoming, and the University of Utah, Salt Lake City, Utah.

Utah↗

Stratigraphic sections of the Phosphoria formation in Wyoming

The first of a series of reports giving detailed stratigraphic sections of the Phosphoria formation in the Western phosphate field as measured and described by the Geological Survey will be released as Circulars within the next few months. Because of the needs of industry for many of these data during the 1951 field season, and in view of the unavoidable delays attendant on publication, the tabular data to be included in these Circulars are hereby placed on open file in simple reproduction form (prepared by Ozalid from photographic negatives) and without explanatory text so that immediate use may be made of the data. The tables include data on sections in four states: Montana, Idaho, Wyoming, and Utah; and the tables for each of these states are bound together as individual reports. The tables include name and location of section measured, brief description of geologic setting, acknowledgments for field and analytical work, abstract data on the sections (bed number, rock name, sample number, and thickness), and analytical data on the samples. The analytical data include reports on P 2 O 5 and acid insoluble for all samples and additional analyses, such as Al 2 0 3 , Fe 7 0 3 , loss on ignition, F, and V 2 O 5 , for selected samples. Spectrographic analyses for a large number of elements are included 2 5, for samples from selected localities, and special analyses have been made of a few samples. These reports are placed on open file at the offices of the Geological Survey in Washington, D. C., Spokane, Washington, Salt Lake City, Utah, and Montpelier, Idaho, and at the offices of the Idaho Bureau of Mines and Geology, Moscow, Idaho, the Montana Bureau of Mines and Geology, Butte, Montana, and the Wyoming Geological Survey, Laramie, Wyoming, and the University of Utah, Salt Lake City, Utah.

Wyoming↗

Water Resources Data, Pennsylvania, Water Year 2002, Volume 2. Susquehanna and Potomac River Basins

Water-resources data for the 2002 water year for Pennsylvania consists of records of discharge and water quality of streams; contents and elevations of lakes and reservoirs; and water levels and water quality of ground-water wells. This report, Volume 2 contains (1) discharge records for 82 continuous-record streamflow-gaging stations, 13 partial-record stations, 24 special study and miscellaneous streamflow sites, and 33 low-flow miscellaneous streamflow sites; (2) elevation and contents records for 12 lake and reservoirs; (3) water-quality records for 33 gaging stations and 104 ungaged streamsites; (4) water-level records for 38 network observation wells; (5) water-quality analyses at 32 special study ground-water wells; and (6) miscellaneous water-level measurements at 31 special study ground-water wells. Site locations are shown in figures throughout the report. Additional water data collected at various sites not involved in the systematic data-collection program are also presented. These data together with the data in Volumes 1 and 3, represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State, local, and Federal agencies in Pennsylvania.

Water Data Report↗

Water resources data, Pennsylvania, water year 2004—Volume 2. Susquehanna and Potomac River basins

Water resources data for the 2004 water year for Pennsylvania consist of records of discharge and water quality of streams; contents and elevations of lakes and reservoirs; and water levels and water quality of ground-water wells. This report, Volume 2 contains (1) discharge records for 85 continuous-record streamflow-gaging stations, 13 partial-record stations, 18 special study and miscellaneous streamflow sites; (2) elevation and contents for 12 lakes and reservoirs, and water-quality records for 12 lakes and reservoirs; (3) water-quality records for 32 gaging stations and 82 ungaged streamsites; (4) water-level records for 40 network observation wells; and (5) water-quality analyses at 46 special study ground-water wells. Site locations are shown in figures throughout the report. Additional water data collected at various sites not involved in the systematic data-collection program are also presented. These data together with the data in Volumes 1 and 3, represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State, local, and Federal agencies in Pennsylvania.

Water Data Report↗

Water Resources Data, Pennsylvania, Water Year 2005, Volume 2. Susquehanna and Potomac River Basins

Water resources data for the 2005 water year for Pennsylvania consist of records of discharge and water quality of streams; contents and elevations of lakes and reservoirs; and water levels and water quality of ground-water wells. This report, Volume 2 contains (1) discharge records for 89 continuous-record streamflow-gaging stations, 13 partial-record stations, 23 special study and miscellaneous streamflow sites; (2) elevation and contents for 12 lakes and reservoirs, and water-quality records for 12 lakes and reservoirs; (3) water-quality records for 33 gaging stations and 68 ungaged streamsites; (4) water-level records for 40 network observation wells; and (5) water-quality analyses at 35 special study ground-water wells. Site locations are shown in figures throughout the report. Additional water data collected at various sites not involved in the systematic data-collection program are also presented. These data together with the data in Volumes 1 and 3, represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State, local, and Federal agencies in Pennsylvania.

Water Data Report↗

Suggestions to authors of the reports of the United States Geological Survey

Knowledge acquired by the Geological Survey through programs of research and investigations has no value to the public if it remains in office files or in the minds of the scientists and engineers who did the work. The full discharge of the Survey's responsibilities is attained only by making its acquired knowledge available promptly and effectively to all people who will find it of interest and use. And, to insure effectiveness, reports must be not only accurate but so clearly and simply written that they are easy to read and understand. Efforts by the Geological Survey to attain high quality in reports are necessarily group efforts. The largest contribution is made by the author, who has assembled facts, has worked out ideas to explain them, and has a direct personal interest in making the facts and ideas clearly and effectively known. The Geological Survey encourages that interest, recognizing that it is an essential ingredient of the high morale of the members of the Survey. Authors should keep in mind, however, that the Survey has a proprietary interest in all their manuscript reports and as proprietor may dispose of the reports, or require that they be changed before publication, as it sees fit. The Survey generally exercises its proprietary interest only to the extent of seeing that a report is scientifically and technically sound, will reach the proper audience, and will reflect credit on both the Survey and the author. To these ends, each report is reviewed by the author's fellow workers, supervisors, and staff officials, who bring to bear upon it their specialized knowledge, skill, judgement to assure a sound product. In its final form each Survey report is that product of team effort in which many persons do their share -- even though most of them remain anonymous. There is no easy way to prepare reports of high quality, any more than there is an easy means of carrying out research to sure and outstanding conclusions. Each task calls for intensive thinking and for preserving work. The author bears the primary responsibility and correspondingly faces the most difficult task. To aid him is the chief purpose of this volume. The subject matter of this volume is arranged under several principal headings. First, a summary is given of the Survey's publications: the historical basis for them, statistics as to what has been issued in the periods 1879-1957, and a list and description of the several series of reports and maps in which material is being published. Next are outlined successive steps that the author will normally take from the start of a project to his final proofreading of the text and illustrations. Under the third broad heading is brought together much detailed information about the form and content of reports. The fourth part of this volume is devoted to advice on expression -- what to seek and what to avoid. A fifth major part of this volume bears on the most common questions of typographic style that affect Survey publications. The final sections of the volume give instructions for typing manuscript copy and correcting the galley and page proofs; also they include a few useful tables and a discussion of the purpose and content of press releases.

Report↗

Water Resources Data, Pennsylvania, Water Year 2002, Volume 3. Ohio and St. Lawrence River Basins

Water-resources data for the 2002 water year for Pennsylvania consists of records of discharge and water quality of streams; contents and elevations of lakes and reservoirs; and water levels and water quality of ground-water wells. This report, Volume 3 contains (1) discharge records for 60 continuous-record streamflow-gaging stations, 5 partial-record stations, and 13 special study and miscellaneous streamflow sites; (2) elevation and contents records for 11 lakes and reservoirs; (3) water-quality records for 23 gaging stations and 33 ungaged streamsites; (4) water-level records for 23 network observation wells; (5) water-quality analyses at 28 special study ground-water wells; and (6) miscellaneous water-level measurements at 31 special study ground-water wells. Site locations are shown in figures throughout the report. Additional water data collected at various sites not involved in the systematic data-collection program are also presented. These data together with the data in Volumes 1 and 2, represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State, local, and Federal agencies in Pennsylvania.

Water Data Report↗

Water resources data, Pennsylvania, water year 1998. Volume 2. Susquehanna and Potomac River basins

Water resources data for the 1998 water year for Pennsylvania consist of records of discharge and water quality of streams; contents and elevations of lakes and reservoirs; and water levels and water quality of ground-water wells. This report, Volume 2, contains (1) discharge records for 85 continuous-record streamflow-gaging stations and 16 partial-record stations, and 23 special study and miscellaneous streamflow sites; (2) elevation and contents records for 12 lakes and reservoirs; (3) water-quality records for 13 gaging stations and 80 ungaged streamsites; (4) water-level records for 30 ground-water network observation wells and water-quality analyses of ground water from 8 wells; and (5) water-quality analyses at 34 special study ground-water wells. Site locations are shown in figures throughout the report. Additional water data collected at various sites not involved in the systematic data-collection program are also presented. These data together with the data in Volumes 1 and 3, represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State, local, and Federal agencies in Pennsylvania.

Pennsylvania↗

The Snowmastodon Project

Studies of terrestrial biotic and environmental dynamics of the last interglacial period, Marine Oxygen Isotope Stage (MIS) 5, provide insight into the effects of long-term climate change on Pleistocene ecosystems. In North America, however, there are relatively few fossil sites that definitively date to MIS 5. Even fewer contain multiple ecosystem components (vertebrates, invertebrates, plants) that have been studied in detail, and none are located at high elevation. Thus, our view of North American ecosystems during MIS 5 is, at best, an incomplete composite view, and alpine ecosystems are entirely undocumented. The Ziegler Reservoir fossil site allows us to begin filling these gaps. Discovered on October 14, 2010 by a construction crew while enlarging a small reservoir near Snowmass Village, Colorado (USA), the site is situated high in the Rocky Mountains at an elevation of ~ 2705 m. Initial excavations exposed a series of stacked fossil ecosystems, including abundant faunal and floral components. Subsequent work revealed an exceptionally diverse biota composed of nearly 6000 large bones of late Pleistocene megafauna, including mastodons, mammoths, ground sloths, horses, camels, deer, bison, black bear, coyotes, and big horn sheep. This collection is complemented by more than 200 bones from at least 40 species of small animals including otters, muskrats, minks, rabbits, beavers, frogs, lizards, snakes, fish, and birds, and more than 20,000 salamander bones. Geomorphic evidence and multiple dating techniques show that the small, ridge-top basin containing the site was formed by a lateral lobe of a valley glacier that filled, and ultimately overtopped, the Snowmass Creek drainage during the Bull Lake glaciation (MIS 6). When the glacier receded, a lake that occupied the basin began to fill slowly with what is hypothesized to be eolian sediment and occasional input from slope failures of the impounding moraine. As sedimentation continued, the lake transformed first into a shallow pond, then a marsh, and later an alpine meadow. In all, the Ziegler Reservoir sedimentary record spans the time encompassed by the end of MIS 6, all of MIS 5 and MIS 4, and the earliest part of MIS 3. MIS 5e, which is considered to be the peak warmth of the last interglacial period, is especially well represented. Preservation of organic material at the Ziegler Reservoir fossil site is exceptional. Even after more than 100,000 years of burial, sedge and willow leaves were still green, mollusks and gastropods showed color, beetle parts remained iridescent, fossil conifer cones were intact, and an entire beach of 20-meter-long driftwood logs was found intact. The exquisite preservation allowed for detailed analysis of pollen, plant macrofossils, conifer cones, and fossil wood, as well as insects, chironomids, mollusks, ostracodes, and other invertebrates — all in addition to the spectacular faunal remains. This special volume of Quaternary Research represents a comprehensive scientific report of “The Snowmastodon Project,” as the investigations at the Ziegler Reservoir fossil site came to be known. Summarizing the work of scientists from more than 20 institutions, the volume details the environments in which the animals lived, provides insight into how they died, and forms the foundation of our understanding of alpine ecosystem dynamics during the last interglacial period in the Rocky Mountains.

Quaternary Research↗

Cross-channel variability in benthic habitat

Benthic invertebrates play an important role in estuarine food webs and biogeochemical cycling of carbon, nutrients, and contaminants. The generally sedentary benthic invertebrates continuously integrate local water, sediment, and food conditions. This makes them good indicators of the type and quality of aquatic habitat at the location where they are found. The Interagency Ecological Program’s Environmental Monitoring Program (EMP) has monitored benthic invertebrates since the mid-1970s. A recent review of the EMP found that the spatial study design of the benthos monitoring element was in need of a thorough reexamination through intense special studies and extensive historic data analyses. This article reports the results of preliminary analyses of historical EMP data focusing on cross-channel variability. Specific questions are: (1) do benthic habitats and community assemblages vary between positions across a river channel? (2) Are benthic samples taken at a single channel position sufficiently representative of benthos assemblages across the channel to characterize long term changes in the benthos community of a particular section of a river?

California↗

Department of the Interior: DOI

Remotely sensed data and derived information contribute substantially to mission-critical work across the Department of the Interior (DOI). 1 This DOI section highlights a sample of DOI remote sensing applications and illustrates a range of technology, platforms, and specialized sensors employed.

conterminous United States↗

Modifications to the modular three-dimensional finite-difference ground-water flow model used for the Columbia Plateau Regional Aquifer-System Analysis, Washington, Oregon, and Idaho

The report documents modifications to the U.S. Geological Survey's modular three-dimensional finite-difference ground-water flow model used for a regional aquifer-system analysis of the Columbia Plateau. The report, which describes the concepts and mathematical basis for the modifications, is intended for potential users who are familiar with the original modular model. The modifications permit flow from a layer to any adjacent layer, allow the model to retain a cell of a layer that has been cut completely through by a canyon, and allow placing ground-water flow barriers on only specified branch conductances; a special version of the modified model uses a convergent grid. The report describes the data-input items that this modified model must read.

Open-File Report↗