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Prioritizing restoration areas to conserve multiple sagebrush-associated wildlife species

Strategic restoration of altered habitat is one method for addressing worldwide biodiversity declines. Within the sagebrush steppe of western North America, habitat degradation has been linked to declines in many species, making restoration a priority for managers; however, limited funding, spatiotemporal variation in restoration success, and the need to manage for diverse wildlife species make decision-making regarding restoration actions challenging. To address the challenge of spatial conservation prioritization, we developed the Prioritizing Restoration of Sagebrush Ecosystems Tool (PReSET). This decision support tool utilizes the prioritizr package in program R and an integer linear programming algorithm to select parcels representing both high biodiversity value and high probability of restoration success. We tested PReSET on a sagebrush steppe system within southwestern Wyoming using distributional data for six species with diverse life histories and a spatial layer of predicted sagebrush recovery times to identify restoration targets at both broad and local scales. While the broad-scale portion of our tool outputs can inform policy, the local-scale results can be applied directly to on-the-ground restoration. We identified restoration priority areas with greater precision than existing spatial prioritizations and incorporated range differences among species. We noted tradeoffs, including that restoring for habitat connectivity may require restoration actions in areas with lower probability of success. Future applications of PReSET will draw from emerging datasets, including spatially-varying economic costs of restoration, animal movement data, and additional species, to further improve our ability to target effective sagebrush restoration.

Wyoming

Vegetation responses to sagebrush-reduction treatments measured by satellites

Time series of vegetative indices derived from satellite imagery constitute tools to measure ecological effects of natural and management-induced disturbances to ecosystems. Over the past century, sagebrush-reduction treatments have been applied widely throughout western North America to increase herbaceous vegetation for livestock and wildlife. We used indices from satellite imagery to 1) quantify effects of prescribed-fire, herbicide, and mechanical treatments on vegetative cover, productivity, and phenology, and 2) describe how vegetation changed over time following these treatments. We hypothesized that treatments would increase herbaceous cover and accordingly shift phenologies towards those typical of grass-dominated systems. We expected prescribed burns would lead to the greatest and most-prolonged effects on vegetative cover and phenology, followed by herbicide and mechanical treatments. Treatments appeared to increase herbaceous cover and productivity, which coincided with signs of earlier senescence − signals expected of grass-dominated systems, relative to sagebrush-dominated systems. Spatial heterogeneity for most phenometrics was lower in treated areas relative to controls, which suggested treatment-induced homogenization of vegetative communities. Phenometrics that explain spring migrations of ungulates mostly were unaffected by sagebrush treatments. Fire had the strongest effect on vegetative cover, and yielded the least evidence for sagebrush recovery. Overall, treatment effects were small relative to those reported from field-based studies for reasons most likely related to sagebrush recovery, treatment specification, and untreated patches within mosaicked treatment applications. Treatment effects were also small relative to inter-annual variation in phenology and productivity that was explained by temperature, snowpack, and growing-season precipitation. Our results indicated that cumulative NDVI, late-season phenometrics, and spatial heterogeneity of several phenometrics may serve as useful indicators of vegetative change in sagebrush ecosystems.

Wyoming

How many tigers Panthera tigris are there in Huai Kha Khaeng Wildlife Sanctuary, Thailand? An estimate using photographic capture-recapture sampling

We used capture-recapture analyses to estimate the density of a tiger Panthera tigris population in the tropical forests of Huai Kha Khaeng Wildlife Sanctuary, Thailand, from photographic capture histories of 15 distinct individuals. The closure test results (z = 0.39, P = 0.65) provided some evidence in support of the demographic closure assumption. Fit of eight plausible closed models to the data indicated more support for model Mh, which incorporates individual heterogeneity in capture probabilities. This model generated an average capture probability = 0.42 and an abundance estimate of = 19 (9.65) tigers. The sampled area of = 477.2 (58.24) km 2 yielded a density estimate of = 3.98 (0.51) tigers per 100 km 2 . Huai Kha Khaeng Wildlife Sanctuary could therefore hold 113 tigers and the entire Western Forest Complex c. 720 tigers. Although based on field protocols that constrained us to use sub-optimal analyses, this estimated tiger density is comparable to tiger densities in Indian reserves that support moderate prey abundances. However, tiger densities in well-protected Indian reserves with high prey abundances are three times higher. If given adequate protection we believe that the Western Forest Complex of Thailand could potentially harbour >2,000 wild tigers, highlighting its importance for global tiger conservation. The monitoring approaches we recommend here would be useful for managing this tiger population.

Huai Kha Khaeng Wildlife Sanctuary

Multi-model comparison highlights consistency in predicted effect of warming on a semi-arid shrub

A number of modeling approaches have been developed to predict the impacts of climate change on species distributions, performance, and abundance. The stronger the agreement from models that represent different processes and are based on distinct and independent sources of information, the greater the confidence we can have in their predictions. Evaluating the level of confidence is particularly important when predictions are used to guide conservation or restoration decisions. We used a multi-model approach to predict climate change impacts on big sagebrush ( Artemisia tridentata ), the dominant plant species on roughly 43 million hectares in the western United States and a key resource for many endemic wildlife species. To evaluate the climate sensitivity of A. tridentata , we developed four predictive models, two based on empirically derived spatial and temporal relationships, and two that applied mechanistic approaches to simulate sagebrush recruitment and growth. This approach enabled us to produce an aggregate index of climate change vulnerability and uncertainty based on the level of agreement between models. Despite large differences in model structure, predictions of sagebrush response to climate change were largely consistent. Performance, as measured by change in cover, growth, or recruitment, was predicted to decrease at the warmest sites, but increase throughout the cooler portions of sagebrush's range. A sensitivity analysis indicated that sagebrush performance responds more strongly to changes in temperature than precipitation. Most of the uncertainty in model predictions reflected variation among the ecological models, raising questions about the reliability of forecasts based on a single modeling approach. Our results highlight the value of a multi-model approach in forecasting climate change impacts and uncertainties and should help land managers to maximize the value of conservation investments.

Global Change Biology

Effects of heptachlor- and lindane-treated seed on Canada geese

A study of Canada geese (B. canadensis) was conducted in the Pacific Northwest from 1978 through 1981. Lowered reproductive success, mortality of adults, and a population decline of resident western Canada geese (B. c. moffitti) at the Umatilla National Wildlife Refuge (Umatilla NWR) Oregon and Washington [USA] were associated with the use of heptachlor-treated wheat. Analyses of eggs and tissues from dead geese provided strong evidence that heptachlor was responsible for the mortality and decreased production. Residues of heptachlor epoxide (HE) in brains of B. c. moffitti found dead in 1978 and 1979 equalled or exceeded the lethal hazard zone of 8-9 .mu.g/g in experimental passerine birds; HE residues of > 10 .mu.g/g in sample eggs were associated with low nest success. The breeding population of Canada geese at Umatilla decreased from 129 pairs in 1974 to about 100 pairs in 1979. The heptachlor problem was restricted to the Umatilla area; HE residues were low in tissues and eggs collected at other sites in Oregon, Washington and Idaho. In Sept., 1979, the use of heptachlor-treated seed was banned in a 1700-km2 area that encompassed both sides of the Columbia River near Umatilla. Lindane was substituted for heptachlor in the restricted area in 1979, and its use was extended to much of the Columbia Basin in 1981. Concurrently, reproductive success of geese increased, mortality decreased, and the nesting population increased to 170 pairs by 1983. There was no evidence for either biomagnification of lindance residues from treated seed to goose tissues or eggs or for induction of adverse effects by this compound.

Oregon, Washington

MOSS user's manual

The Map Overlay and Statistical System (MOSS) Users' Manual is specialized document has been designed for trained users of the MOSS interactive graphics software. Those totally unfamiliar with MOSS or Geographic Information Systems are referred elsewhere as described below: -- If you know nothing about MOSS or what it can do for you, and you wish introductory information on MOSS, or you want to deign an application and data entry process compatible with MOSS, or you want "hands-on" training, contact the WELUT Team Leader at the address below for a "hands-on" GIS training session. -- If you have been introduced to MOSS, have your application defined, data entered, and want to know how to use MOSS, start reading at Section 1 of this Manual. --If you are interested in the MOSS data structure, refer to Section 2 of this Manual. --If you have some experience in using MOSS and want to refer to the general types of MOSS commands, read Section 3 of this Manual. --If you are an experience MOSS user and want details on individual MOSS commands, refer to Section 4.3 of this Manual. --If you are interested in the Federation of Rocky Mountain States -- WELUT 02 Project contractual background results, turn to Appendices D and E of this Manual. MOSS has been operation for less than 3 months, and has received limited operational testing at the date of this printing (October 1978). Undiscovered software limitations and bugs may yet appear. All such bugs as well as documentation errors, obscurities, and inadequacies should be reported to: Team Leader Western Energy and Land Use Team (WELUT) U.S. Fish and Wildlife Service Drake Creekside Building 2625 Redwing Road Fort Collins, Colorado 80526

FWS/OBS

Multi-species inference of exotic annual and native perennial grasses in rangelands of the western United States using Harmonized Landsat and Sentinel-2 data

The invasion of exotic annual grass (EAG), e.g., cheatgrass ( Bromus tectorum ) and medusahead ( Taeniatherum caput-medusae ), into rangeland ecosystems of the western United States is a broad-scale problem that affects wildlife habitats, increases wildfire frequency, and adds to land management costs. However, identifying individual species of EAG abundance from remote sensing, particularly at early stages of invasion or growth, can be problematic because of overlapping controls and similar phenological characteristics among native and other exotic vegetation. Subsequently, refining and developing tools capable of quantifying the abundance and phenology of annual and perennial grass species would be beneficial to help inform conservation and management efforts at local to regional scales. Here, we deploy an enhanced version of the U.S. Geological Survey Rangeland Exotic Plant Monitoring System to develop timely and accurate maps of annual (2016–2020) and intra-annual (May 2021 and July 2021) abundances of exotic annual and perennial grass species throughout the rangelands of the western United States. This monitoring system leverages field observations and remote-sensing data with artificial intelligence/machine learning to rapidly produce annual and early season estimates of species abundances at a 30-m spatial resolution. We introduce a fully automated and multi-task deep-learning framework to simultaneously predict and generate weekly, near-seamless composites of Harmonized Landsat Sentinel-2 spectral data. These data, along with auxiliary datasets and time series metrics, are incorporated into an ensemble of independent XGBoost models. This study demonstrates that inclusion of the Normalized Difference Vegetation Index and Normalized Difference Wetness Index time-series data generated from our deep-learning framework enables near real-time and accurate mapping of EAG (Median Absolute Error (MdAE): 3.22, 2.72, and 0.02; and correlation coefficient (r): 0.82, 0.81, and 0.73; respectively for EAG, cheatgrass, and medusahead) and native perennial grass abundance (MdAE: 2.51, r:0.72 for Sandberg bluegrass ( Poa secunda )). Our approach and the resulting data provide insights into rangeland grass dynamics, which will be useful for applications, such as fire and drought monitoring, habitat suitability mapping, as well as land-cover and land-change modelling. Spatially explicit, timely, and accurate species-specific abundance datasets provide invaluable information to land managers.

western United States

Minnesota landowners’ trust in their department of natural resources, salient values similarity and wildlife value orientations

Due to extensive land conversion over the last century, much of the native prairie pothole ecosystem has been converted to agricultural or other human uses. The prairie pothole ecosystem is found in the northern plains of Iowa, Minnesota, South Dakota, North Dakota, and Montana. Because most of the land in this region is privately owned and used for agricultural production, most impacts to wildlife habitat are the result of decisions by individual landowners. Landowner trust in natural resource management agencies is important for agencies to effectively accomplish their mission. We measured the nature (competence and fairness) and level of trust that western Minnesota landowners have in the Minnesota Department of Natural Resources (MnDNR) and landowners’ wildlife value orientations (WVO). Landowners rated MnDNR slightly higher in competence than fairness; however, these two dimensions were strongly correlated. We developed a MnDNR trust scale (six items) and a three-cluster model dividing landowners along the MnDNR trust scale, which we named Negative (28%), Neutral (43%), and Positive (29%). We provide evidence supporting the salient values similarity (SVS) model that states people have trust in agencies holding similar values; landowners reporting greater importance for wildlife consideration when making land-use decisions also reported greater trust in the MnDNR. In addition, mutualist landowners had the highest trust in the MnDNR and utilitarian landowners the lowest level of trust, which is opposite of the trust relationship reported for the general public with state wildlife agencies. Based on the SVS model, our results suggest that mutualist landowners perceive greater congruence with MnDNR goals related to wildlife habitat compared to utilitarian landowners.

Minnesota

2005 annual progress report: Elk and bison grazing ecology in the Great Sand Dunes complex of lands

In 2000 the U.S. Congress authorized the expansion of the former Great Sand Dunes National Monument by establishing a new Great Sand Dunes National Park and Preserve in its place, and establishing the Baca National Wildlife Refuge. The establishment of Great Sand Dunes National Park and Preserve and the new Baca National Wildlife Refuge in the San Luis Valley (SLV), Colorado was one of the most significant land conservation actions in the western U.S. in recent years. The action was a result of cooperation between the National Park Service (NPS), U.S. Fish and Wildlife Service (USFWS), Bureau of Land Management (BLM), U.S. Forest Service (USDA-FS), and The Nature Conservancy (TNC). The new national park, when fully implemented, will consist of 107,265 acres, the new national preserve 41,872 acres, and the new national wildlife refuge (USFWS lands) 92,180 acres (fig. 1). The area encompassed by this designation protects a number of natural wonders and features including a unique ecosystem of natural sand dunes, the entire watershed of surface and groundwaters that are necessary to preserve and recharge the dunes and adjacent wetlands, a unique stunted forest, and other valuable riparian vegetation communities that support a host of associated wildlife and bird species. When the National Park was initially established, there were concerns about overconcentrations and impacts on native plant communities of the unhunted segments of a large and possibly growing elk (Cervus elaphus) population. This led to the designation of the Preserve as a compromise solution, where the elk could be harvested. The Preserve Unit, however, will not address all the ungulate management challenges. In order to reduce the current elk population, harvests of elk may need to be aggressive. But aggressive special hunts of elk to achieve population reductions can result in elk avoidance of certain areas or elk seeking refuge in areas where they cannot be hunted, while removals of whole herd segments and abandonment or alterations of migration routes can occur (Smith and Robbins, 1994; Boyce and others, 1991). Elk may seek refuge from hunting in the newly expanded Park Unit and TNC lands where they might overconcentrate and impact unique vegetation communities. In these sites of refugia, or preferred loafing sites, elk and bison could accelerate a decline in woody riparian shrubs and trees. This decline may also be due to changes in hydrology, climatic, or dunal processes, but ungulate herbivory might exacerbate the effects of those processes. To address the questions and needs of local resource managers, a multi-agency research project was initiated in 2005 to study the ecology, forage relations, and habitat relations of elk and bison in the Great Sand Dunes–Sangre de Cristo–Baca complex of lands. Meetings and discussions of what this research should include were started in 2001 with representatives from NPS, USFWS, TNC, the Colorado Division of Wildlife (CDOW), and USDA-FS/BLM. The final study plan was successfully funded in 2004 with research scheduled to start in 2005. The research was designed to encompass three major study elements: (1) animal movements and population dynamics, (2) vegetation and nutrient effects from ungulate herbivory, and (3) development of ecological models, using empirical data collected from the first two components, that will include estimates of elk carrying capacity and management scenarios for resource managers.

Colorado

Ungulate migrations of the Western United States, volume 4

Broadly distributed across the Western United States, ungulates (hooved mammals) play an important role in ecosystem function by affecting vegetation communities and forming the prey base for large carnivores. Additionally, ungulates provide economic benefits to regional communities through tourism and hunting and hold cultural significance for many Tribal communities. Many ungulates migrate seasonally between distinct summer and winter ranges to take advantage of spatially and temporally variable food sources and avoid threats such as predators and deep snow. Increasingly, these migrations are threatened by the growing human footprint and associated subdivisions, energy development, and increased traffic volume. Efforts to study ungulate populations and conserve their migrations received support in recent years from the U.S. Department of the Interior Secretarial Order No. 3362, which provided Federal support for enhancing habitat quality for ungulates across the Western States. In response to Secretarial Order No. 3362, the U.S. Geological Survey (USGS) established the Corridor Mapping Team, a collaboration among USGS and participating State and Federal wildlife management agencies and numerous Tribal Nations. Together, the Corridor Mapping Team maps ungulate migrations throughout the Western United States in the USGS “Ungulate Migrations of the Western United States” report series. This report (volume 4) details migrations and seasonal ranges from 31 new herds throughout nine Western States. Additionally, this report includes updates to two herds published in previous reports. Including this report, the report series has provided the mapped migrations and seasonal ranges of 182 unique herds and has provided a map-based inventory of the documented ungulate migrations across the Western United States for biologists, managers, policy makers, and conservation practitioners. This report also discusses how the mapping efforts associated with the Corridor Mapping Team can be used to guide management and policy regarding renewable energy development and ungulate disease, specifically chronic wasting disease, in the Western United States.

Arizona, California, Colorado, New Mexico, Nevada,

Greater Sage-Grouse National Research Strategy

The condition of the sagebrush ecosystem has been declining in the Western United States, and greater sage-grouse (Centrocercus urophasianus), a sagebrush-obligate species, has experienced concurrent decreases in distribution and population numbers. This has prompted substantial research and management over the past two decades to improve the understanding of sage-grouse and its habitats and to address the observed decreases in distribution and population numbers. The amount of research and management has increased as the year 2015 approaches, which is when the U.S. Fish and Wildlife Service (FWS) is expected to make a final decision about whether or not to protect the species under the Endangered Species Act. In 2012, the Sage-Grouse Executive Oversight Committee (EOC) of the Western Association of Fish and Wildlife Agencies (WAFWA) requested that the U.S. Geological Survey (USGS) lead the development of a Greater Sage-Grouse National Research Strategy (hereafter Research Strategy). This request was motivated by a practical need to systematically connect existing research and conservation plans with persisting or emerging information needs. Managers and researchers also wanted to reduce redundancy and help focus limited funds on the highest priority research and management issues. The USGS undertook the development of this Research Strategy, which addresses information and science relating to the greater sage-grouse and its habitat across portions of 11 Western States. This Research Strategy provides an outline of important research topics to ensure that science information gaps are identified and documented in a comprehensive manner. Further, by identifying priority topics and critical information needed for planning, research, and resource management, it provides a structure to help coordinate members of an expansive research and management community in their efforts to conduct priority research.

California, Colorado, Idaho, Montana, Nevada, Nort

One Health in action: Flea control and interpretative education at Badlands National Park

One Health involves interdisciplinary collaboration to improve, protect, and preserve the health of humans, wildlife, and ecosystems, and advocates for unified approaches to One Health challenges (Buttke et al. 2015). Here, we focus on a One Health challenge of nearly global distribution: Yersinia pestis , the flea-borne bacterial agent of plague. The bacterium poses a significant risk to humans and wildlife, causing social strife in some regions and transforming ecosystems (Eads and Biggins 2015). The conservation implications are profound in the western United States, where Y. pestis was first introduced in 1900. Considerable effort is devoted to plague mitigation, sometimes for human or wildlife health purposes separately. We present a synergy between plague mitigation for human and wildlife health.

South Dakota

Survey of bats on Columbia National Wildlife Refuge, Washington, December 2011-April 2012

Bats are diverse and abundant in many ecosystems worldwide. They perform important ecosystem functions, particularly by consuming large quantities of insects (Cleveland and others, 2006; Jones and others, 2009; Kuhn and others, 2011). The importance of bats to biodiversity and to ecosystem integrity has been overlooked in many regions, largely because the challenges of detecting and studying these small, nocturnal mammals have rendered a paucity of information on matters as basic as species distribution and natural history attributes. Recently, concern for bats has arisen in response to recognition of large-scale threats, such as white-nosed syndrome (WNS; Turner and others, 2009; Frick and others, 2010) and mortality at wind energy facilities (Arnett and others, 2008), factors that are causing unprecedented population declines of bats (Boyles and others, 2011). WNS is a fungal disease that has killed more than 1 million cave-hibernating bats in eastern North America since being discovered in New York State in 2006 (U.S. Fish and Wildlife Service, 2012). WNS has spread rapidly from northeastern U.S., and as of August 2012 has been confirmed as far west as eastern Missouri(U.S. Fish and Wildlife Service, 2013). Given the rapid spread of WNS, there is concern that the disease may soon affect western bat populations. Hibernating bats are particularly vulnerable to the effects of WNS (Blehert and others, 2009). Refuges in eastern Washington, including the Mid-Columbia River National Wildlife Refuge Complex (MCRNWRC) and Little Pend Oreille National Wildlife Refuge, support many potential hibernacula. Sixteen species of bats potentially occur on these refuges, including one federally listed species of concern (Townsend’s big-eared bat [Corynorhinus townsendii]; see table 1 for scientific names of bats), and 12 species that are of conservation concern in Washington and Oregon (table 1). However, little is known about bats on these refuges because few surveys have been done, and none have been done during winter. Refuge biologists are lacking even the most basic information, such as species presence, and location and status of hibernacula. In order to assess vulnerability and develop a strategy for management of WNS, refuge managers need to know where bats are hibernating, and which species are using each hibernaculum. The goal of this project was to provide information on the status of wintering bats to refuge biologists and managers in order to support decision-making that might minimize the threat of WNS in western bat populations. We conducted surveys of bat activity in winter and early spring as an initial step toward identifying bat species that may be over-wintering and locating potential hibernacula on these refuges. Our specific objectives were to identify bat species using the refuges, to identify areas of resident bat activity in autumn, winter, and early spring using acoustic bat detectors, and to try new methods for quick surveys of bat activity.

Oregon;Washington

Habitat manipulation influences northern bobwhite resource selection on a reclaimed surface mine

More than 600,000 ha of mine land have been reclaimed in the eastern United States, providing large contiguous tracts of early successional vegetation that can be managed for northern bobwhite ( Colinus virginianus ). However, habitat quality on reclaimed mine land can be limited by extensive coverage of non-native invasive species, which are commonly planted during reclamation. We used discrete-choice analysis to investigate bobwhite resource selection throughout the year on Peabody Wildlife Management Area, a 3,330-ha reclaimed surface mine in western Kentucky. We used a treatment-control design to study resource selection at 2 spatial scales to identify important aspects of mine land vegetation and whether resource selection differed between areas with habitat management (i.e., burning, disking, herbicide; treatment) and unmanaged units (control). Our objectives were to estimate bobwhite resource selection on reclaimed mine land and to estimate the influence of habitat management practices on resource selection. We used locations from 283 individuals during the breeding season (1 Apr–30 Sep) and 136 coveys during the non-breeding season (1 Oct–Mar 31) from August 2009 to March 2014. Individuals were located closer to shrub cover than would be expected at random throughout the year. During the breeding season, individuals on treatment units used areas with smaller contagion index values (i.e., greater interspersion) compared with individuals on control units. During the non-breeding season, birds selected areas with greater shrub-open edge density compared with random. At the microhabitat scale, individuals selected areas with increased visual obstruction >1 m aboveground. During the breeding season, birds were closer to disked areas (linear and non-linear) than would be expected at random. Individuals selected non-linear disked areas during winter but did not select linear disked areas (firebreaks) because they were planted to winter wheat each fall and lacked cover during the non-breeding season. Individuals also selected areas treated with herbicide to control sericea lespedeza ( Lespedeza cuneata ) throughout the year. During the breeding season, bobwhites avoided areas burned during the previous dormant season. Habitat quality of reclaimed mine lands may be limited by a lack of shrub cover and extensive coverage of non-native herbaceous vegetation. Managers aiming to increase bobwhite abundance should focus on increasing interspersion of shrub cover, with no area >100 m from shrub cover. We suggest disking and herbicide application to control invasive species and improve the structure and composition of vegetation for bobwhites.

Kentucky

Amphibians in the climate vise: loss and restoration of resilience of montane wetland ecosystems in the western US

Wetlands in the remote mountains of the western US have undergone two massive ecological “experiments” spanning the 20th century. Beginning in the late 1800s and expanding after World War II, fish and wildlife managers intentionally introduced millions of predatory trout (primarily Oncorhynchus spp) into fishless mountain ponds and lakes across the western states. These new top predators, which now occupy 95% of large mountain lakes, have limited the habitat distributions of native frogs, salamanders, and wetland invertebrates to smaller, more ephemeral ponds where trout do not survive. Now a second “experiment” – anthropogenic climate change – threatens to eliminate many of these ephemeral habitats and shorten wetland hydroperiods. Caught between climate-induced habitat loss and predation from introduced fish, native mountain lake fauna of the western US – especially amphibians – are at risk of extirpation. Targeted fish removals, guided by models of how wetlands will change under future climate scenarios, provide innovative strategies for restoring resilience of wetland ecosystems to climate change.

Western United States

The literature of the California black rail

Few birds have remained so little known as the California black rail ( Laterallus jamaicensis coturniculus ). Although first collected in 1859 or before and reported in 1874 (Ridgway 1874), its life history, distribution, and status have remained so obscure that even a sight record of the bird is deemed worthy of a report in some ornithological publications. Because degradation and loss of freshwater and saltwater marshlands in California may be detrimentally affecting the black rail, both the U.S. Bureau of Sport Fisheries and Wildlife (1973) and the California Department of Fish and Game (1972) have classified it as rare and worthy of further study. The 84 papers and notes both summarized in this report and included in its bibliography include essentially all that is currently known about the California black rail. Only 11 of these papers consider the life history of this rail in any detail. The rest are distribution notes and some of the more important papers on the closely related eastern black rail ( L. j. jamaicensis ). The latter are included for comparative purposes, or because they may lend clues to currently unknown facets of the life history of the western race.

Special Scientific Report - Wildlife

Modeling potential impacts of the Garrison Diversion Unit project on Sand Lake and Arrowwood National Wildlife Refuges: a feasibility analysis

The Garrison Diversion Unit (GDU) of the Pick-Sloan Missouri Basin program was authorized in 1965, with the purpose of diverting Missouri River water to the James River for irrigation, municipal and industrial water supply, fish and wildlife habitat, recreation, and flood control. The project was reauthorized in 1986, with the specification that comprehensive studies be conducted to address a variety of issues. One of these ongoing studies addresses potential impacts of GDU construction and operation on lands of the National Wildlife Refuge (NWR) system, including Arrowwood and Sand Lake Refuges (the Refuges) on the James River. A number of concerns at these Refuges have been identified; the primary concerns addressed in this report include increased winter return flows, which would limit control of rough fish; increased turbidity during project construction, which would decrease production of sago pondweed; and increased water level fluctuations in the late spring and early summer, which would destroy the nests of some over-water nesting birds. The facilitated workshop described in this report was conducted February 18-20, 1987, under the joint sponsorship of the U.S. Bureau of Reclamation, the U.S. Fish and Wildlife Service, and the North Dakota Game and Fish Department. The primary objectives of the workshop were to evaluate the feasibility of using simulation modeling techniques to estimate GDU impacts on Arrowwood and Sand Lake Refuges and to suggest enhancements to the James River Refuge monitoring program. The workshop was structured around the formulation of four submodels: a Hydrology and Water Quality submodel to simulate changes in Refuge pool elevations, turnover rates, and water quality parameters (e.g., total dissolved solids, turbidity, dissolved oxygen, nutrients, water temperature, pesticides) due to GDU construction and operation; a Vegetation submodel to simulate concomitant changes in wetland communities (e.g., sago pondweed, wet meadows, deep and shallow marsh); a Fish submodel to estimate changes in abundance or biomass of rough fish (carp, buffalo) and sportfish (northern pike); and a Wildlife submodel to calculate indices of waterfowl abundance or habitat suitability (e.g., for mallards, western grebes, migrating diving ducks, white-faced ibis, egrets, over-water nesters). Submodels considered weekly to monthly changes in pools within a Refuge over a time horizon of 30-50 years. Based on workshop discussions and past experience with impact analysis modeling, a phased modeling approach was recommended for the James River Refuges analysis. The first phase would involve two modeling efforts. The existing Sand Lake hydrology model, and a similar one developed for Arrowwood NWR, would be validated and used to predict changes on pool elevations and winter inflows to each pool for a variety of GDU alternatives. Outputs from simulations would then be evaluated in terms of potential fish and wildlife impacts. For example, the models could generate indices comparing the magnitude and timing of winter inflows for pre- and postproject conditions; fisheries biologists could then use these indices to better quantify their concerns relative to potential changes in the frequency of rough-fish control. The other modeling effort in the first phase would involve developing a sago pondweed growth model to integrate Refuge monitoring data and existing literature and perhaps to address some questions concerning turbidity impacts. A second phase of simulation modeling would be undertaken only if the initial analyses of hydrologic outputs indicated significant potential problems and if monitoring and research projects had clarified some of the biological and physical processes that cannot be modeled reliably at the present time (e.g., resuspension of sediments by carp, immigration and winter mortality of fish, loss of waterfowl nests due to wave action). The second phase would attempt to develop an integrated impact assessment model. In order to address some of the biological and physical processes that presently are not well understood, a number of studies and enhancements to the Refuge monitoring program were suggested. The Hydrology and Water Quality workgroup recommended increasing turbidity and dissolved oxygen sampling, dropping expensive analysis of some trace elements, adding more pesticide analysis (including some biological monitoring), and developing better area-capacity data for the Sand Lake hydrology model. The Vegetation workgroup suggested expanding the number of monitoring stations, monitoring photosynthetically active radiation by depth, and modifying the biomass sampling procedure and schedule. Also suggested were additional analyses of existing Refuge monitoring data and additional field studies concerning sago growth under a variety of environmental conditions and effects of rough fish density on sago. A careful examination of Refuge narrative reports was recommended by the Fish workgroup to characterize conditions that led to various rates of winter-kill. Monitoring enhancement related to a better understanding of fish population dynamics included increasing dissolved oxygen monitoring, continuing present monitoring of fish movement upstream from Jamestown Reservoir into Arrowwood NWR, initiating similar efforts for upstream movement into Sand Lake NWR and downstream movements into both Refuges, and augmenting the present gillnetting program (or replacing it) with sampling for population and age/size structure estimates. The Wildlife workgroup suggested estimating the relative density of mallard nests in over-water and wet meadow nesting areas, estimating the number of western grebe nests lost due to wave action, delineating wet meadows on the Refuge vegetation maps, estimating annual tuber consumption by birds, and monitoring insect/macroinvertebrate abundance. The workgroup also suggested research studies to better understand the relationships between food supplies and the growth and survival of ducklings and young grebes. the workshop discussions also helped identify some suggestions for modifying project features that, if feasible from an engineering and operational standpoint, would reduce impacts on Refuge lands. These suggestions included: designing drains with control structures or small "reregulation" reservoirs to hold winter return flows that might adversely affect rough fish control, spreading construction activities over a number of years to reduce potential impacts of turbidity on sago pondweed in any single year, scheduling construction to occur after the spring sprouting and elongation growth stages to reduce impacts on sago pondweed, and installing "quick acting" control structures at Arrowwood NWR to reduce pool level fluctuations that might destroy nests of some over-water nesting waterfowl.

Report

Soil criteria to protect terrestrial wildlife and open-range livestock from metal toxicity at mining sites

Thousands of hard rock mines exist in the western USA and in other parts of the world as a result of historic and current gold, silver, lead, and mercury mining. Many of these sites in the USA are on public lands. Typical mine waste associated with these sites are tailings and waste rock dumps that may be used by wildlife and open-range livestock. This report provides wildlife screening criteria levels for metals in soil and mine waste to evaluate risk and to determine the need for site-specific risk assessment, remediation, or a change in management practices. The screening levels are calculated from toxicity reference values based on maximum tolerable levels of metals in feed, on soil and plant ingestion rates, and on soil to plant uptake factors for a variety of receptors. The metals chosen for this report are common toxic metals found at mining sites: arsenic, cadmium, copper, lead, mercury, and zinc. The resulting soil screening values are well above those developed by the US Environmental Protection Agency. The difference in values was mainly a result of using toxicity reference values that were more specific to the receptors addressed rather than the most sensitive receptor.

Environmental Monitoring and Assessment