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At least 685 records · Page 38Linked to original sources
USGS2001

Status and distribution of the West Indian manatee, Trichechus manatus manatus, in Colombia

Historical and recent information on the status and distribution of West Indian manatee, Trichechus manatus manatus, in Colombia was reviewed. Opportunistic and systematic interviews were also conducted. Historical information suggested that the distribution of manatees had been reduced in the Caribbean basin. Manatees can be found in the Atrato, Sinu??, San Jorge, Cauca, Cesar and Magdalena rivers and the Cie??naga Grande de Santa Marta marsh in the Caribbean basin, and in the Meta River in the Orinoco basin. The Magdalena riparian system provides the largest area of suitable habitat, which also has the highest frequency of captures. Most animals (81.20%) were killed for sale or to share meat in a subsistence base. Hunting is apparently increasing but capture with nets still represents the species' major direct threat. Habitat destruction occurs in all areas. International and national laws protect the species, however, funding is inadequate for effective enforcement of present laws. ?? 2001 Published by Elsevier Science Ltd. All rights reserved.

Biological Conservation↗
USGS2022

Potential effects of energy development on environmental resources of the Williston Basin in Montana, North Dakota, and South Dakota—Species of conservation concern

The ecosystems of the Williston Basin provide direct and indirect benefits to society. These benefits include carbon sequestration, flood control, nutrient rich soils for agricultural productivity, and habitat for wildlife. This chapter’s main focus is on the effects of energy development on species that occupy the ecosystems in the Williston Basin. We compiled a list of documented species of conservation concern that are of most interest to Federal regulators and resource managers. Species of concern were either listed as endangered or threatened under the Endangered Species Act or listed by States as species of concern in Natural Heritage Program checklists or State Wildlife Action Plans. All told, we determined that 357 species of concern likely occupy the Williston Basin. These species represented seven different taxonomic groups: plants (native and nonnative), terrestrial invertebrates, birds, mammals, reptiles and amphibians, and fish and mussels. We reviewed the existing scientific information pertaining to potential effects of energy development on these taxonomic groups. Currently, little is known about the abundance and distribution of many of these species. But some information exists that may be useful in predicting the potential effects of energy development on certain taxonomic groups. Most of this information has been developed through scientific research focused on effects to mammal and bird populations. Effects to other taxonomic groups seems to be understudied. In general, it seems that disturbances and modifications associated with development have the potential to negatively affect a wide range of species; however, many studies produce uncertain results because they are not designed to compare populations before and after energy development takes place. Most of these studies also do not monitor resources over multiple years and thus cannot detect population trends. Likewise, there are few examples of landscape-scale assessments of the cumulative effects of energy development that could be used for species or habitat management purposes. We suggest that more research needs to be completed to measure potential effects to a broad range of species in multiple taxonomic groups. This may require also developing some understanding about the basic ecology of many of the species covered in this report. In concert with this more basic research, we also suggest that more comprehensive assessments of potential negative cumulative effects across the Williston Basin should be developed in an effort to guide more strategic management of biological resources.

Montana, North Dakota, South Dakota↗
USGS2022

Representing plant diversity in land models: An evolutionary approach to make ‘Functional Types’ more functional

Plants are critical mediators of terrestrial mass and energy fluxes, and their structural and functional traits have profound impacts on local and global climate, biogeochemistry, biodiversity, and hydrology. Yet Earth System Models (ESMs), our most powerful tools for predicting the effects of humans on the coupled biosphere-atmosphere system, simplify the incredible diversity of land plants into a handful of coarse categories of ‘Plant Functional Types’ (PFTs) that often fail to capture ecological dynamics such as biome distributions. The inclusion of more realistic functional diversity is a recognized goal for ESMs, yet there is currently no consistent, widely accepted way to add diversity to models, i.e. to determine what new PFTs to add and with what data to constrain their parameters. We review approaches to representing plant diversity in ESMs and draw on recent ecological and evolutionary findings to present an evolution-based functional type approach for further disaggregating functional diversity. Specifically, the prevalence of niche conservatism, or the tendency of closely related taxa to retain similar ecological and functional attributes through evolutionary time, reveals that evolutionary relatedness is a powerful framework for summarizing functional similarities and differences among plant types. We advocate that Plant Functional Types based on dominant evolutionary lineages (‘Lineage Functional Types’) will provide an ecologically defensible, tractable, and scalable framework for representing plant diversity in next-generation ESMs, with the potential to improve parameterization, process representation, and model benchmarking. We highlight how the importance of evolutionary history for plant function can unify the work of disparate fields to improve predictive modeling of the Earth system.

Global Change Biology↗
USGS2006

Understanding barriers to implementation of an adaptive land management program

The Florida Fish and Wildlife Conservation Commission manages over 650,000 ha, including 26 wildlife management and environmental areas. To improve management, they developed an objective-based vegetation management (OBVM) process that focuses on desired conditions of plant communities through an adaptive management framework. Our goals were to understand potential barriers to implementing OBVM and to recommend strategies to overcome barriers. A literature review identified 47 potential barriers in six categories to implementation of adaptive and ecosystem management: logistical, communication, attitudinal, institutional, conceptual, and educational. We explored these barriers through a bureau-wide survey of 90 staff involved in OBVM and personal interviews with area managers, scientists, and administrators. The survey incorporated an organizational culture assessment instrument to gauge how institutional factors might influence OBVM implementation. The survey response rate was 69%. Logistics and communications were the greatest barriers to implementing OBVM. Respondents perceived that the agency had inadequate resources for implementing OBVM and provided inadequate information. About one-third of the respondents believed OBVM would decrease their job flexibility and perceived greater institutional barriers to the approach. The 43% of respondents who believed they would have more responsibility under OBVM also had greater attitudinal barriers. A similar percentage of respondents reported OBVM would not give enough priority to wildlife. Staff believed that current agency culture was hierarchical but preferred a culture that would provide more flexibility for adaptive management and would foster learning from land management activities. In light of the barriers to OBVM, we recommend the following: (1) mitigation of logistical barriers by addressing real and perceived constraints of staff, funds, and other resources in a participatory manner; (2) mitigation of communication barriers through interpersonal and electronic communication channels; (3) development of an OBVM external advisory committee; and (4) adoption of characteristics of an organizational culture that promotes flexibility and learning. ??2006 Society for Conservation Biology.

Conservation Biology↗
USGS2005

Effects of biodiversity on ecosystem functioning: a consensus of current knowledge

Humans are altering the composition of biological communities through a variety of activities that increase rates of species invasions and species extinctions, at all scales, from local to global. These changes in components of the Earth's biodiversity cause concern for ethical and aesthetic reasons, but they also have a strong potential to alter ecosystem properties and the goods and services they provide to humanity. Ecological experiments, observations, and theoretical developments show that ecosystem properties depend greatly on biodiversity in terms of the functional characteristics of organisms present in the ecosystem and the distribution and abundance of those organisms over space and time. Species effects act in concert with the effects of climate, resource availability, and disturbance regimes in influencing ecosystem properties. Human activities can modify all of the above factors; here we focus on modification of these biotic controls. The scientific community has come to a broad consensus on many aspects of the relationship between biodiversity and ecosystem functioning, including many points relevant to management of ecosystems. Further progress will require integration of knowledge about biotic and abiotic controls on ecosystem properties, how ecological communities are structured, and the forces driving species extinctions and invasions. To strengthen links to policy and management, we also need to integrate our ecological knowledge with understanding of the social and economic constraints of potential management practices. Understanding this complexity, while taking strong steps to minimize current losses of species, is necessary for responsible management of Earth's ecosystems and the diverse biota they contain. Based on our review of the scientific literature, we are certain of the following conclusions: 1) Species' functional characteristics strongly influence ecosystem properties. Functional characteristics operate in a variety of contexts, including effects of dominant species, keystone species, ecological engineers, and interactions among species (e.g., competition, facilitation, mutualism, disease, and predation). Relative abundance alone is not always a good predictor of the ecosystem-level importance of a species, as even relatively rare species (e.g., a keystone predator) can strongly influence pathways of energy and material flows. 2) Alteration of biota in ecosystems via species invasions and extinctions caused by human activities has altered ecosystem goods and services in many well-documented cases. Many of these changes are difficult, expensive, or impossible to reverse or fix with technological solutions. 3) The effects of species loss or changes in composition, and the mechanisms by which the effects manifest themselves, can differ among ecosystem properties, ecosystem types, and pathways of potential community change. 4) Some ecosystem properties are initially insensitive to species loss because (a) ecosystems may have multiple species that carry out similar functional roles, (b) some species may contribute relatively little to ecosystem properties, or (c) properties may be primarily controlled by abiotic environmental conditions. 5) More species are needed to insure a stable supply of ecosystem goods and services as spatial and temporal variability increases, which typically occurs as longer time periods and larger areas are considered. We have high confidence in the following conclusions: 1) Certain combinations of species are complementary in their patterns of resource use and can increase average rates of productivity and nutrient retention. At the same time, environmental conditions can influence the importance of complementarity in structuring communities. Identification of which and how many species act in a complementary way in complex communities is just beginning. 2) Susceptibility to invasion by exotic species is strongly influenced by species composition and, under similar environmental conditions, generally decreases with increasing species richness. However, several other factors, such as propagule pressure, disturbance regime, and resource availability also strongly influence invasion success and often override effects of species richness in comparisons across different sites or ecosystems. 3) Having a range of species that respond differently to different environmental perturbations can stabilize ecosystem process rates in response to disturbances and variation in abiotic conditions. Using practices that maintain a diversity of organisms of different functional effect and functional response types will help preserve a range of management options. Uncertainties remain and further research is necessary in the following areas: 1) Further resolution of the relationships among taxonomic diversity, functional diversity, and community structure is important for identifying mechanisms of biodiversity effects. 2) Multiple trophic levels are common to ecosystems but have been understudied in biodiversity/ecosystem functioning research. The response of ecosystem properties to varying composition and diversity of consumer organisms is much more complex than responses seen in experiments that vary only the diversity of primary producers. 3) Theoretical work on stability has outpaced experimental work, especially field research. We need long-term experiments to be able to assess temporal stability, as well as experimental perturbations to assess response to and recovery from a variety of disturbances. Design and analysis of such experiments must account for several factors that covary with species diversity. 4) Because biodiversity both responds to and influences ecosystem properties, understanding the feedbacks involved is necessary to integrate results from experimental communities with patterns seen at broader scales. Likely patterns of extinction and invasion need to be linked to different drivers of global change, the forces that structure communities, and controls on ecosystem properties for the development of effective management and conservation strategies. 5) This paper focuses primarily on terrestrial systems, with some coverage of freshwater systems, because that is where most empirical and theoretical study has focused. While the fundamental principles described here should apply to marine systems, further study of that realm is necessary. Despite some uncertainties about the mechanisms and circumstances under which diversity influences ecosystem properties, incorporating diversity effects into policy and management is essential, especially in making decisions involving large temporal and spatial scales. Sacrificing those aspects of ecosystems that are difficult or impossible to reconstruct, such as diversity, simply because we are not yet certain about the extent and mechanisms by which they affect ecosystem properties, will restrict future management options even further. It is incumbent upon ecologists to communicate this need, and the values that can derive from such a perspective, to those charged with economic and policy decision-making.

Ecological Monographs↗
USGS2017

States and rates: Complementary approaches to developing flow‐ecology relationships

In recognition of the influence of flow on riverine habitats and organisms, stream ecologists have devoted considerable effort to the development of quantitative predictive relationships describing ecological responses to flow variability, i.e. flow‐ecology relationships. Methods used to generate flow‐ecology relationships can be thought of as a continuum bookended by pure states approaches on one end and by rates approaches on the other. In pure states approaches, the ecological response is a snapshot of a condition or property (i.e. a state) derived from a single measurement in time. In contrast, ecological responses in rates approaches reflect temporal change (i.e. a rate) and are thus reliant on repeated measurements made over time. Here, we elaborate on the fundamental characteristics of different approaches (pure states, rates and an intermediate approach we call repeated states) for generating flow‐ecology relationships, examine how commonly the different approaches are used in the flow‐ecology literature, conduct an independent analysis to illustrate the different outcomes achieved by applying repeated‐states and rates approaches using a dataset for stream fish diversity in relation to flow magnitude, and identify some of the different ways ecologists are applying rates approaches in flow ecology. Our literature review revealed that repeated‐states approaches (53% of reviewed studies) were used far more commonly than either pure states (19%) or rates (12%) approaches to generate flow‐ecology relationships. The remaining hybrid studies (17%) used both state and rate responses, and thus also relied on repeated measurements over time. Despite frequent collection of data suitable for rates approaches, flow‐ecology relationships have generally been developed using states approaches that relate changes in ecological states to different long‐term average flow conditions, rather than to specific flow sequences over much shorter time intervals. Such flow‐ecology relationships cannot generate temporally specific predictions of ecological responses to changing flow conditions (i.e. the expected change in state following a specific flow sequence), nor can they describe demographic processes underlying observed changes. While there are different scenarios in which a pure or repeated‐states approach would be useful, more frequent use of rates approaches would increase our ability to test flow‐ecology hypotheses and our mechanistic understanding of flow‐ecology relationships.

Freshwater Biology↗
USGS2015

Urgent need for warming experiments in tropical forests

Although tropical forests account for only a fraction of the planet's terrestrial surface, they exchange more carbon dioxide with the atmosphere than any other biome on Earth, and thus play a disproportionate role in the global climate. In the next 20 years, the tropics will experience unprecedented warming, yet there is exceedingly high uncertainty about their potential responses to this imminent climatic change. Here, we prioritize research approaches given both funding and logistical constraints in order to resolve major uncertainties about how tropical forests function and also to improve predictive capacity of earth system models. We investigate overall model uncertainty of tropical latitudes and explore the scientific benefits and inevitable trade-offs inherent in large-scale manipulative field experiments. With a Coupled Model Intercomparison Project Phase 5 analysis, we found that model variability in projected net ecosystem production was nearly 3 times greater in the tropics than for any other latitude. Through a review of the most current literature, we concluded that manipulative warming experiments are vital to accurately predict future tropical forest carbon balance, and we further recommend the establishment of a network of comparable studies spanning gradients of precipitation, edaphic qualities, plant types, and/or land use change. We provide arguments for long-term, single-factor warming experiments that incorporate warming of the most biogeochemically active ecosystem components (i.e. leaves, roots, soil microbes). Hypothesis testing of underlying mechanisms should be a priority, along with improving model parameterization and constraints. No single tropical forest is representative of all tropical forests; therefore logistical feasibility should be the most important consideration for locating large-scale manipulative experiments. Above all, we advocate for multi-faceted research programs, and we offer arguments for what we consider the most powerful and urgent way forward in order to improve our understanding of tropical forest responses to climate change.

Global Change Biology↗
USGS1989

Assessment of smolt condition for travel time analysis. Annual report 1988

Estimates of migration rates and travel times of juvenile salmonids within index reaches of the Columbia River basin are collected through the Smolt Monitoring Program for use by the Fish Passage Center. With increased reliance upon travel time estimates in 1988 by the Fish Passage Center, this study was implemented to monitor the biological attributes of juvenile chinook salmon Oncorhynchus tshawytscha and steelhead trout 0.- mykiss used for the travel time estimates, The physiological ability of fish to respond to stress was assessed by measuring levels of plasma cortisol, glucose, and chloride before and after a stress-challenge test. Most mid-Columbia and Snake river groups responded normally to the stress challenge exhibiting an increase in plasma glucose and cortisol and a slight decrease in chloride. Fish trucked to release sites were more stressed than those released directly from the hatchery, but most still responded to the stress challenge test normally. An abnormal or extreme stress response occurred when there were deviations from preferred protocol, disease problems at hatcheries, or when fish were trucked over long periods (7h). The development of smoltification was evaluated by measuring gill Na+K+-ATPase, plasma thyroxine, purines, and body morphology. Most groups were similar at the hatcheries but differed as the migration to McNary Dam proceeded. Gill ATPase activity increased 2-3 fold during the first 20 days of migration, after which it changed little. Fish with longer in-river travel times appeared to be more smolted than those which were in the river for a shorter period of time. The prevalence of bacterial kidney disease (BKD) in spring chinook salmon was evaluated using the enzyme linked immunosorbent assay (ELISA) and fluorescent antibody technique (FAT). Prevalence of BKD in groups tested using the ELISA method was as high as 99% at some downstream locations. A review of indices is presented as a guide, to the development of an index of smolt condition and preliminary data are presented. An index could be used as a tool to synthesize information on fish condition to assist with management and evaluation of the Water Budget.

Report↗
USGS2020

The assessment and remediation of mercury contaminated sites: A review of current approaches

Remediation of mercury (Hg) contaminated sites has long relied on traditional approaches, such as removal and containment/capping. Here we review contemporary practices in the assessment and remediation of industrial-scale Hg contaminated sites and discuss recent advances. Significant improvements have been made in site assessment, including the use of XRF to rapidly identify the spatial extent of contamination, Hg stable isotope fractionation to identify sources and transformation processes, and solid-phase characterization (XAFS) to evaluate Hg forms. The understanding of Hg bioavailability for methylation has been improved by methods such as sequential chemical extractions and porewater measurements, including the use of diffuse gradient in thin-film (DGT) samplers. These approaches have shown varying success in identifying bioavailable Hg fractions and further study and field applications are needed. The downstream accumulation of methylmercury (MeHg) in biota is a concern at many contaminated sites. Identifying the variables limiting/controlling MeHg production—such as bioavailable inorganic Hg, organic carbon, and/or terminal electron acceptors (e.g. sulfate, iron) is critical. Mercury can be released from contaminated sites to the air and water, both of which are influenced by meteorological and hydrological conditions. Mercury mobilized from contaminated sites is predominantly bound to particles, highly correlated with total sediment solids (TSS), and elevated during stormflow. Remediation techniques to address Hg contamination can include the removal or containment of Hg contaminated materials, the application of amendments to reduce mobility and bioavailability, landscape/waterbody manipulations to reduce MeHg production, and food web manipulations through stocking or extirpation to reduce MeHg accumulated in desired species. These approaches often rely on knowledge of the Hg forms/speciation at the site, and utilize physical, chemical, thermal and biological methods to achieve remediation goals. Overall, the complexity of Hg cycling allows many different opportunities to reduce/mitigate impacts, which creates flexibility in determining suitable and logistically feasible remedies.

Science of the Total Environment↗
USGS2014

A multiscale, hierarchical model of pulse dynamics in arid-land ecosystems

Ecological processes in arid lands are often described by the pulse-reserve paradigm, in which rain events drive biological activity until moisture is depleted, leaving a reserve. This paradigm is frequently applied to processes stimulated by one or a few precipitation events within a growing season. Here we expand the original framework in time and space and include other pulses that interact with rainfall. This new hierarchical pulse-dynamics framework integrates space and time through pulse-driven exchanges, interactions, transitions, and transfers that occur across individual to multiple pulses extending from micro to watershed scales. Climate change will likely alter the size, frequency, and intensity of precipitation pulses in the future, and arid-land ecosystems are known to be highly sensitive to climate variability. Thus, a more comprehensive understanding of arid-land pulse dynamics is needed to determine how these ecosystems will respond to, and be shaped by, increased climate variability.

Annual Review of Ecology, Evolution, and Systemati↗
USGS2023

Achieving water quality goals in the Chesapeake Bay: A comprehensive evaluation of system response

A Comprehensive Evaluation of System Response Achieving Water Quality Goals in the Chesapeake Bay: A Comprehensive Evaluation of System Response (CESR) includes an evaluation of why progress toward meeting the TMDL and water quality standards has been slower than expected and offers options for how progress can be accelerated. This report is a summation of a three year investigation into the 40 year effort to reduce nutrient loads to Chesapeake Bay. History The effort began as a STAC independent initiative in March 2019, after Kurt Stephenson, Zach Easton, and Brian Benham proposed the idea of a report that would identify gaps and uncertainties in system response—physical, chemical, biological, and socioeconomic—that impact efforts designed to attain water quality standards in Chesapeake Bay. As STAC Chair at the time, Benham facilitated the development of a collaborative process that would engage the entire committee. As a first step in approaching the long causal chain that links management actions to their eventual impact on water quality and living resources, workgroups were formed around the subsystems of this chain: nutrient and sediment reductions (watershed), water quality response to nutrient and sediment reductions (estuary) and living resource response to water quality (living resources). Each of these workgroups generated an independent document with a self-determined scope (i.e., workgroups were afforded flexibility to address issues beyond the original objectives). Because the content of each document was both unique and substantial, STAC chose to publish them as stand-alone documents with authorship attribution. In the second step, a steering committee developed a series of framing questions to guide the preparation of this report that would meet the objective of identifying gaps and uncertainties in achieving the Bay TMDL and water quality standards. Coeditors Stephenson and Wardrop, supported to great extent by a subgroup of the Steering Committee (Leonard Shabman, Zach Easton, Jeremy Testa, William Dennison, Kenny Rose, and Mark Monaco) were tasked with assembling ideas and contributions to write a single draft text, drawing material from the aforementioned resource documents, STAC and Chesapeake Bay Program reports, the scientific literature, and a limited amount of additional analyses performed in collaboration with Bay Program scientists. The resulting report was then submitted for several reviews by both steering committee members and the membership at-large to produce a consensus report.

Maryland, Virginia↗
USGS2011

Setting limits: Using air pollution thresholds to protect and restore U.S. ecosystems

More than four decades of research provide unequivocal evidence that sulfur, nitrogen, and mercury pollution have altered, and will continue to alter, our nation's lands and waters. The emission and deposition of air pollutants harm native plants and animals, degrade water quality, affect forest productivity, and are damaging to human health. Many air quality policies limit emissions at the source but these control measures do not always consider ecosystem impacts. Air pollution thresholds at which ecological effects are observed, such as critical loads, are effective tools for assessing the impacts of air pollution on essential ecosystem services and for informing public policy. U.S. ecosystems can be more effectively protected and restored by using a combination of emissions-based approaches and science-based thresholds of ecosystem damage. Based on the results of a comprehensive review of air pollution thresholds, we conclude: ??? Ecosystem services such as air and water purification, decomposition and detoxification of waste materials, climate regulation, regeneration of soil fertility, production and biodiversity maintenance, as well as crop, timber and fish supplies are impacted by deposition of nitrogen, sulfur, mercury and other pollutants. The consequences of these changes may be difficult or impossible to reverse as impacts cascade throughout affected ecosystems. ??? The effects of too much nitrogen are common across the U.S. and include altered plant and lichen communities, enhanced growth of invasive species, eutrophication and acidification of lands and waters, and habitat deterioration for native species, including endangered species. ??? Lake, stream and soil acidification is widespread across the eastern United States. Up to 65% of lakes within sensitive areas receive acid deposition that exceeds critical loads. ??? Mercury contamination adversely affects fish in many inland and coastal waters. Fish consumption advisories for mercury exist in all 50 states and on many tribal lands. High concentrations of mercury in wildlife are also widespread and have multiple adverse effects. ??? Air quality programs, such as those stemming from the 1990 Clean Air Act Amendments, have helped decrease air pollution even as population and energy demand have increased. Yet, they do not adequately protect ecosystems from long-term damage. Moreover they do not address ammonia emissions. ??? A stronger ecosystem basis for air pollutant policies could be established through adoption of science-based thresholds. Existing monitoring programs track vital information needed to measure the response to policies, and could be expanded to include appropriate chemical and biological indicators for terrestrial and aquatic ecosystems and establishment of a national ecosystem monitoring network for mercury. The development and use of air pollution thresholds for ecosystem protection and management is increasing in the United States, yet threshold approaches remain underutilized. Ecological thresholds for air pollution, such as critical loads for nitrogen and sulfur deposition, are not currently included in the formal regulatory process for emissions controls in the United States, although they are now considered in local management decisions by the National Park Service and U.S. Forest Service. Ecological thresholds offer a scientifically sound approach to protecting and restoring U.S. ecosystems and an important tool for natural resource management and policy. ?? The Ecological Society of America.

Issues in Ecology↗
USGS2026

Constructed value of information with iterative scoring and parametric uncertainty to identify management-relevant research priorities for a declining raptor species

Constructed value of information (CVoI) is an expert elicitation decision-analytic tool used to prioritize sources of uncertainty based on their potential to improve decision outcomes if resolved. Despite increased application of CVoI, the robustness of CVoI prioritization of sources of uncertainty relative to differences in expert elicitation and scoring methods has not been evaluated. We engaged a group of species experts in a decision-analytic process to elicit uncertainties, framed as alternative hypotheses, about current population declines of the American kestrel ( Falco sparverius ) in the United States. Participants scored 13 hypotheses across 3 CVoI criteria, which are defined as constructed scales. Rather than experts selecting a single score per criterion, we used a likelihood point method to incorporate parametric uncertainty in the scoring process, in which experts were given 100 points to distribute across possible score categories within the criterion-specific constructed scale. Experts provided scores over 2 scoring rounds, with an opportunity to review and discuss initial scores between rounds. We used a Shannon entropy calculation to quantify how evenly participants allotted their points. We used simulation to evaluate the robustness of our prioritization results relative to a scoring method in which participants selected a single score category for each criterion. Participants often spread their points across 2 adjacent scores, reflecting parametric uncertainty. For one third of the hypothesis-scoring round combinations, the prioritization results differed in approximately 50% of simulations. The highest scoring hypotheses related to how the use of artificial versus natural nest cavities affects fecundity or survival, whether winter roosting sites are a limiting factor for population growth, and whether gamebird habitat management may benefit kestrel populations. Our CVoI prioritization framework can be used to develop collaborative research that is directly relevant to a management decision and is an advance in eliciting more representative expert beliefs.

Conservation Biology↗
USGS2007

Design and implementation of estimation-based monitoring programs for flora and fauna: A case study on the Cherokee National Forest

Science-based monitoring of biological resources is important for a greater understanding of ecological systems and for assessment of the target population using theoretic-based management approaches. When selecting variables to monitor, managers first need to carefully consider their objectives, the geographic and temporal scale at which they will operate, and the effort needed to implement the program. Generally, monitoring can be divided into two categories: index and inferential. Although index monitoring is usually easier to implement, analysis of index data requires strong assumptions about consistency in detection rates over time and space, and parameters are often biasednot accounting for detectability and spatial variation. In most cases, individuals are not always available for detection during sampling periods, and the entire area of interest cannot be sampled. Conversely, inferential monitoring is more rigorous because it is based on nearly unbiased estimators of spatial distribution. Thus, we recommend that detectability and spatial variation be considered for all monitoring programs that intend to make inferences about the target population or the area of interest. Application of these techniques is especially important for the monitoring of Threatened and Endangered (T&E) species because it is critical to determine if population size is increasing or decreasing with some level of certainty. Use of estimation-based methods and probability sampling will reduce many of the biases inherently associated with index data and provide meaningful information with respect to changes that occur in target populations. We incorporated inferential monitoring into protocols for T&E species spanning a wide range of taxa on the Cherokee National Forest in the Southern Appalachian Mountains. We review the various approaches employed for different taxa and discuss design issues, sampling strategies, data analysis, and the details of estimating detectability using site occupancy. These techniques provide a science-based approach for monitoring and can be of value to all resource managers responsible for management of T&E species.

Proceedings of the Annual Conference of the Southe↗
USGS2015

Unifying research on the fragmentation of terrestrial and aquatic habitats: patches, connectivity and the matrix in riverscapes

While there is an increasing emphasis in terrestrial ecology on determining the influence of the area that surrounds habitat patches (the landscape ‘matrix’) relative to the characteristics of the patches themselves, research on these aspects in running waters is still rather underrepresented. Here we outline conceptual foundations of matrix ecology for stream and river ecosystems (‘riverscapes’). We discuss how a hierarchical, patch-based perspective is necessary for the delineation of habitat patches and the surrounding matrix, through which we may identify two classes of habitat edges in riverscapes (i.e. edges between the terrestrial–aquatic interface and edges within streams). Under this conceptual framework, we discuss the role of the matrix in influencing between-patch movement, and resource quality and quantity within and among habitat patches in riverscapes. We also review types of empirical and modelling approaches which may advance our understanding of fragmentation effects in these systems. We identify five key challenges for understanding fragmentation and matrix effects more completely: (i) defining populations and their status (i.e. quantifying the demographic contribution of habitat patches to metapopulation dynamics), (ii) scaling from metapopulations to metacommunities (particularly searching for generalities in species responses to landscape heterogeneity), (iii) scaling from metacommunities to metaecosystems (i.e. exploring the interactive role of the terrestrial–aquatic and within-stream matrix effects on the flow of material and energy at the network scale), (iv) understanding temporal dynamics in matrix permeability and (v) revealing the utility of different patch and matrix representations for modelling connectivity relationships. Fragmentation of habitats is a critical issue in the conservation and management of stream networks across spatial scales. Although the effects of individual barriers (e.g. dams) are well documented, we argue that a more comprehensive patch–matrix landscape model will improve our understanding of fragmentation effects and improve management in riverscapes.

Freshwater Biology↗
USGS2016

Research on Golden-winged Warblers: Recent progress and current needs

Considerable advances have been made in knowledge about Golden-winged Warblers ( Vermivora chrysoptera ) in the past decade. Recent employment of molecular analysis, stable-isotope analysis, telemetry-based monitoring of survival and behavior, and spatially explicit modeling techniques have added to, and revised, an already broad base of published knowledge. Here, we synthesize findings primarily from recent peer-reviewed literature on Golden-winged Warblers, from this volume and elsewhere, and we identify some of the substantial remaining research needs. We have organized this synthesis by stages of the Golden-winged Warbler annual cycle. First, we discuss the relatively well-studied breeding-grounds ecology including nesting and post-fledging ecology and hybridization with closely related Blue-winged Warblers ( Vermivora cyanoptera ). Second, we discuss the much-less-studied, non-breeding-grounds ecology, including the first empirical studies of non-breeding-grounds cover-type associations and spatial and social behavioral ecology. Third, we address migratory connectivity and migration ecology, for which little is known and research has only just begun. Last, we close with cautious optimism that current knowledge is adequate to inform initial conservation and management plans for Golden-winged Warblers, and with a sobering acknowledgement of the quantity of research still needed.

Studies in Avian Biology↗
USGS2018

Winter feeding of elk in the Greater Yellowstone Ecosystem and its effects on disease dynamics

Providing food to wildlife during periods when natural food is limited results in aggregations that may facilitate disease transmission. This is exemplified in western Wyoming where institutional feeding over the past century has aimed to mitigate wildlife–livestock conflict and minimize winter mortality of elk ( Cervus canadensis ). Here we review research across 23 winter feedgrounds where the most studied disease is brucellosis, caused by the bacterium Brucella abortus . Traditional veterinary practices (vaccination, test-and-slaughter) have thus far been unable to control this disease in elk, which can spill over to cattle. Current disease-reduction efforts are being guided by ecological research on elk movement and density, reproduction, stress, co-infections and scavengers. Given the right tools, feedgrounds could provide opportunities for adaptive management of brucellosis through regular animal testing and population-level manipulations. Our analyses of several such manipulations highlight the value of a research–management partnership guided by hypothesis testing, despite the constraints of the sociopolitical environment. However, brucellosis is now spreading in unfed elk herds, while other diseases (e.g. chronic wasting disease) are of increasing concern at feedgrounds. Therefore experimental closures of feedgrounds, reduced feeding and lower elk populations merit consideration.

Wyoming↗
USGS2002

On the origin of brucellosis in bison of Yellowstone National Park: a review

Brucellosis caused by Brucella abortus occurs in the free-ranging bison ( Bison bison ) of Yellowstone and Wood Buffalo National Parks and in elk ( Cervus elaphus ) of the Greater Yellowstone Area. As a result of nationwide bovine brucellosis eradication programs, states and provinces proximate to the national parks are considered free of bovine brucellosis. Thus, increased attention has been focused on the wildlife within these areas as potential reservoirs for transmission to cattle. Because the national parks are mandated as natural areas, the question has been raised as to whether Brucella abortus is endogenous or exogenous to bison, particularly for Yellowstone National Park. We synthesized diverse lines of inquiry, including the evolutionary history of both bison and Brucella , wild animals as Brucella hosts, biochemical and genetic information, behavioral characteristics of host and organism, and area history to develop an evaluation of the question for the National Park Service. All lines of inquiry indicated that the organism was introduced to North America with cattle, and that the introduction into the Yellowstone bison probably was directly from cattle shortly before 1917. Fistulous withers of horses was a less likely possibility. Elk on winter feedgrounds south of Yellowstone National Park apparently acquired the disease directly from cattle. Bison presently using Grand Teton National Park probably acquired brucellosis from feedground elk.

Idaho, Montana, Wyoming↗