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Geography for a Changing World - A science strategy for the geographic research of the U.S. Geological Survey, 2005-2015

This report presents a science strategy for the geographic research of the U.S. Geological Survey (USGS) for the years 2005-2015. The common thread running through the vision, mission, and science goals presented in the plan is that USGS geographers will provide national leadership to understand coupled human-environmental systems in the face of land change and will deliver pertinent information to decisionmakers on the vulnerability and resilience of these systems. We define land change science as the study of the human and environment dynamics that give rise to changed land use, cover, and surface form. A number of realities shape the strategic context of this plan: The Department of Interior Strategic Plan focuses on meeting society’s resource needs and sustaining the Nation’s life support systems, underscoring the importance of characterizing and understanding coupled human-environmental systems. In redefining its mission in the mid-1990s, the USGS envisions itself as an integrated natural science and information agency. The USGS will assume a national leadership role in the use of science to develop knowledge about the web of relations that couple biophysical and human systems and translate this knowledge into unbiased, reliable information that meets important societal information needs. The following trends will influence USGS geography-oriented science activities over the next decade. Most of the emerging earth science issues that the USGS will address are geographic phenomena. A growing international concern for aligning society’s development activities with environmental limits has led to an articulation of a science agenda associated with global environmental change, vulnerability, and resilience. Earth science investigations have evolved toward the study of very large areas, and the resulting huge volumes of data are challenging to manage and understand. Finally, scientists and the public face the challenge of gaining intelligent insights about geographic and environmental processes from these data, with the ultimate goal of guiding resource-management decisions. The first four science goals in the plan support understanding the human and environmental dynamics of land change. Each science goal has an associated set of strategic actions to achieve the goal. These goals and actions are consistent with national science priorities and the Department of Interior and USGS missions, take advantage of existing expertise, and lead to the strengthening of critical geographic research capacities that do not exist in other USGS disciplines.

Circular

College and university environmental programs as a policy problem (Part 2): Strategies for improvement

Environmental studies and environmental sciences programs in American and Canadian colleges and universities seek to ameliorate environmental problems through empirical enquiry and analytic judgment. In a companion article (Part 1) we describe the environmental program movement (EPM) and discuss factors that have hindered its performance. Here, we complete our analysis by proposing strategies for improvement. We recommend that environmental programs re-organize around three principles. First, adopt as an overriding goal the concept of human dignity—defined as freedom and social justice in healthy, sustainable environments. This clear higher-order goal captures the human and environmental aspirations of the EPM and would provide a more coherent direction for the efforts of diverse participants. Second, employ an explicit, genuinely interdisciplinary analytical framework that facilitates the use of multiple methods to investigate and address environmental and social problems in context. Third, develop educational programs and applied experiences that provide students with the technical knowledge, powers of observation, critical thinking skills and management acumen required for them to become effective professionals and leaders. Organizing around these three principles would build unity in the EPM while at the same time capitalizing on the strengths of the many disciplines and diverse local conditions involved.

Environmental Management

Adaptive harvest management for the Svalbard population of Pink-Footed Geese: 2014 progress summary

This document describes progress to date on the development of an adaptive harvest-management strategy for maintaining the Svalbard population of pink-footed geese (Anser brachyrhynchus) near their agreed target level (60 thousand) by providing for sustainable harvests in Norway and Denmark. Specifically, this report provides an assessment of the most recent monitoring information and its implications for the harvest management strategy. The development of a passively adaptive harvest management strategy requires specification of four elements: (a) a set of alternative population models, describing the effects of harvest and other relevant environmental factors; (b) a set of probabilities describing the relative credibility of the alternative models, which are updated each year based on a comparison of model predictions and monitoring information; (c) a set of alternative harvest quotas, from which a 3-year quota is chosen; and (d) an objective function, by which alternative harvest strategies can be evaluated and an optimal strategy chosen. By combining varying hypotheses about survival and reproduction, a suite of nine models have been developed that represent a wide range of possibilities concerning the extent to which demographic rates are density dependent or independent, and the extent to which spring temperatures are important. Five of the models incorporate density-dependent mechanisms that would maintain the population near a carrying capacity (i.e., in the absence of harvest) of 65k – 129k depending on the specific model. The remaining four models are density independent and predict an exponentially growing population even with moderate levels of harvest. The most current set of monitoring information was used to update model weights for the period 1991 – 2013. Current model weights suggest little or no evidence for density-dependent survival and reproduction. These results suggest that the pink-footed goose population may have recently experienced a release from density-dependent mechanisms, corresponding to the period of most rapid growth in population size. There was equivocal evidence for the effect of May temperature days (number of days with temperatures above freezing: TempDays) on survival and on reproduction. During the summer of 2013 we computed an optimal harvest strategy for the 3-year period 2013 – 2015. The strategy suggested that the appropriate annual harvest quota is 15 thousand. The 1-year harvest strategy calculated to determine whether an emergency closure of the hunting season is required this year suggested an allowable harvest of 25.0 thousand; thus, a hunting-season closure is not warranted. If the harvest quota of 15 thousand were met in the coming hunting season, the next population count would be expected to be 71.0 thousand. If only the most recent 4-year mean harvest were realized (11.3 thousand), a population size of 74.8 thousand would be expected. Simulations suggest that it will take approximately seven years at current harvest levels to reduce population size to the goal of 60 thousand. However, it is possible that the extension of the forthcoming hunting season in Denmark could result in a total harvest approaching 15 thousand; in this case, simulations suggest it would only take about three years to reach the goal.

Svalbard

Sediment transport modeling in Lake Ontario embayments: Impacts on fish spawning substrates

Anthropogenically-driven sedimentation changes have had adverse environmental impacts on aquatic environments, including reductions in fish spawning habitats in embayments worldwide. This study was motivated by the need to understand the impacts of waves and current-driven sedimentation patterns on traditional spawning areas and their effect on sustainable fish reproduction in the Great Lakes. Coupled hydrodynamic, wave, and sediment transport models were developed within the Delft3D-SWAN (DS) framework to predict sedimentation patterns in two embayments in Lake Ontario, Sodus Bay and Chaumont Bay, that have been historically important fish spawning habitats. These bays, with distinct geomorphic characteristics and connectivity to Lake Ontario, offer an opportunity to examine how wind-generated waves and currents impact bed shear stress and subsequent sedimentation patterns. Areas experiencing greater wave-induced bed shear stress were identified and compared between the two bays. Simulated sediment transport patterns showed notable erosion near the lake-bay connections and increased deposition in the inner areas of both embayments. Observed Cisco embryo deposition corresponded to regions of high sheer stress and lower sedimentation, indicating physical attributes in those areas that are important for embryo survival. These results show where sediment settling and erosion occur in the two bays and highlight potential impacts on traditional spawning areas.

New York

USGS St. Petersburg Coastal and Marine Science Center

Extreme storms, sea-level rise, and the health of marine communities are some of the major societal and environmental issues impacting our Nation's marine and coastal realm. The U.S. Geological Survey (USGS) in St. Petersburg, Fla., investigates processes related to these ecosystems and the societal implications of natural hazards and resource sustainability. As one of three centers nationwide conducting research within the USGS Coastal and Marine Geology Program, the center is integral towards developing an understanding of physical processes that will contribute to rational decisions regarding the use and stewardship of national coastal and marine environments.

Florida

A review and synthesis of recreation ecology research supporting carrying capacity and visitor use management decisionmaking

Resource and experiential impacts associated with visitation to wilderness and other similar backcountry settings have long been addressed by land managers under the context of “carrying capacity” decisionmaking. Determining a maximum level of allowable use, below which high-quality resource and experiential conditions would be sustained, was an early focus in the 1960s and 1970s. However, decades of recreation ecology research have shown that the severity and areal extent of visitor impact problems are influenced by an interrelated array of use-related, environmental, and managerial factors. This complexity, with similar findings from social science research, prompted scientists and managers to develop more comprehensive carrying capacity frameworks, including a new Visitor Use Management framework. These frameworks rely on a diverse array of management strategies and actions, often termed a “management toolbox,” for resolving visitor impact problems. This article reviews the most recent and relevant recreation ecology studies that have been applied in wildland settings to avoid or minimize resource impacts. The key findings and their management implications are highlighted to support the professional management of common trail, recreation site, and wildlife impact problems. These studies illustrate the need to select from a more diverse array of impact management strategies and actions based on an evaluation of problems to identify the most influential factors that can be manipulated.

Journal of Forestry

Pacific salmonines in the Great Lakes Basin

Pacific salmon (genus Oncorhynchus) are a valuable resource, both within their native range in the North Pacific rim and in the Great Lakes basin. Understanding their value from a biological and economic perspective in the Great Lakes, however, requires an understanding of changes in the ecosystem and of management actions that have been taken to promote system stability, integrity, and sustainable fisheries. Pacific salmonine introductions to the Great Lakes are comprised mainly of Chinook salmon, coho salmon, and steelhead and have accounted for 421, 177, and 247 million fish, respectively, stocked during 1966-2007. Stocking of Pacific salmonines has been effective in substantially reducing exotic prey fish abundances in several of the Great Lakes (e.g., lakes Michigan, Huron, and Ontario). The goal of our evaluation was to highlight differences in management strategies and perspectives across the basin, and to evaluate policies for Pacific salmonine management in the Great Lakes. Currently, a potential conflict exists between Pacific salmonine management and native fish rehabilitation goals because of the desire to sustain recreational fisheries and to develop self-sustaining populations of stocked Pacific salmonines in the Great Lakes. We provide evidence that suggests Pacific salmonines have not only become naturalized to the food webs of the Great Lakes, but that their populations (specifically Chinook salmon) may be fluctuating in concert with specific prey (i.e., alewives) whose populations are changing relative to environmental conditions and ecosystem disturbances. Remaining questions, however, are whether or not “natural” fluctuations in predator and prey provide enough “stability” in the Great Lakes food webs, and even more importantly, would a choice by managers to attempt to reduce the severity of predator-prey oscillations be antagonistic to native fish restoration efforts. We argue that, on each of the Great Lakes, managers are pursuing appropriate goals, managing the aquatic resources of the lakes for the greatest public good, given the variability in conditions and likelihood for success specific to each lake.

Book chapter

Geodatabase compilation of hydrogeologic, remote sensing, and water-budget-component data for the High Plains aquifer, 2011

The High Plains aquifer underlies almost 112 million acres in the central United States. It is one of the largest aquifers in the Nation in terms of annual groundwater withdrawals and provides drinking water for 2.3 million people. The High Plains aquifer has gained national and international attention as a highly stressed groundwater supply primarily because it has been appreciably depleted in some areas. The U.S. Geological Survey has an active program to monitor the changes in groundwater levels for the High Plains aquifer and has documented substantial water-level changes since predevelopment: the High Plains Groundwater Availability Study is part of a series of regional groundwater availability studies conducted to evaluate the availability and sustainability of major aquifers across the Nation. The goals of the regional groundwater studies are to quantify current groundwater resources in an aquifer system, evaluate how these resources have changed over time, and provide tools to better understand a systems response to future demands and environmental stresses. The purpose of this report is to present selected data developed and synthesized for the High Plains aquifer as part of the High Plains Groundwater Availability Study. The High Plains Groundwater Availability Study includes the development of a water-budget-component analysis for the High Plains completed in 2011 and development of a groundwater-flow model for the northern High Plains aquifer. Both of these tasks require large amounts of data about the High Plains aquifer. Data pertaining to the High Plains aquifer were collected, synthesized, and then organized into digital data containers called geodatabases. There are 8 geodatabases, 1 file geodatabase and 7 personal geodatabases, that have been grouped in three categories: hydrogeologic data, remote sensing data, and water-budget-component data. The hydrogeologic data pertaining to the northern High Plains aquifer is included in three separate geodatabases: (1) base data from a groundwater-flow model; (2) hydrogeology and hydraulic properties data; and (3) groundwater-flow model data to be used as calibration targets. The remote sensing data for this study were developed by the U. S. Geological Survey Earth Resources Observation and Science Center and include historical and predicted land-use/land-cover data and actual evapotranspiration data by using remotely sensed temperature data. The water-budget-component data contains selected raster data from maps in the “Selected Approaches to Estimate Water-Budget Components of the High Plains, 1940 Through 1949 and 2000 Through 2009” report completed in 2011 ( http://pubs.usgs.gov/sir/2011/5183/ ). Federal Geographic Data Committee compliant metadata were created for each spatial and tabular data layer in the geodatabases.

Colorado, Kansas, Nebraska, New Mexico, Oklahoma,

Potentiometric Surface in the Sparta-Memphis Aquifer of the Mississippi Embayment, Spring 2007

The most widely used aquifer for industry and public supply in the Mississippi embayment in Arkansas, Louisiana, Mississippi, and Tennessee is the Sparta-Memphis aquifer. Decades of pumping from the Sparta-Memphis aquifer have affected ground-water levels throughout the Mississippi embayment. Regional assessments of water-level data from the aquifer are important to document regional water-level conditions and to develop a broad view of the effects of ground-water development and management on the sustainability and availability of the region's water supply. This information is useful to identify areas of water-level declines, identify cumulative areal declines that may cross State boundaries, evaluate the effectiveness of ground-water management strategies practiced in different States, and identify areas with substantial data gaps that may preclude effective management of ground-water resources. A ground-water flow model of the northern Mississippi embayment is being developed by the Mississippi Embayment Regional Aquifer Study (MERAS) to aid in answering questions about ground-water availability and sustainability. The MERAS study area covers parts of eight states including Alabama, Arkansas, Illinois, Kentucky, Louisiana, Mississippi, Missouri, and Tennessee and covers approximately 70,000 square miles. The U.S. Geological Survey (USGS) and the Mississippi Department of Environmental Quality Office of Land and Water Resources measured water levels in wells completed in the Sparta-Memphis aquifer in the spring of 2007 to assist in the MERAS model calibration and to document regional water-level conditions. Measurements by the USGS and the Mississippi Department of Environmental Quality Office of Land and Water Resources were done in cooperation with the Arkansas Natural Resources Commission; the Arkansas Geological Survey; Memphis Light, Gas and Water; Shelby County, Tennessee; and the city of Germantown, Tennessee. In 2005, total water use from the Sparta-Memphis aquifer in the Mississippi embayment was about 540 million gallons per day (Mgal/d). Water use from the Sparta-Memphis aquifer was about 170 Mgal/d in Arkansas, about 68 Mgal/d in Louisiana, about 97 Mgal/d in Mississippi, and about 205 Mgal/d in Tennessee. The author acknowledges, with great appreciation, the efforts of the personnel in the U.S. Geological Survey Water Science Centers of Arkansas, Kentucky, Louisiana, Mississippi, Missouri, and Tennessee, and the Mississippi Department of Environmental Quality Office of Land and Water Resources that participated in the planning, water-level measurement, data evaluation, and review of the potentiometric-surface map. Without the contribution of data and the technical assistance of their staffs, this report would not have been completed.

Scientific Investigations Map

The South Florida Ecosystem Portfolio Model - A Map-Based Multicriteria Ecological, Economic, and Community Land-Use Planning Tool

The South Florida Ecosystem Portfolio Model (EPM) prototype is a regional land-use planning Web tool that integrates ecological, economic, and social information and values of relevance to decision-makers and stakeholders. The EPM uses a multicriteria evaluation framework that builds on geographic information system-based (GIS) analysis and spatially-explicit models that characterize important ecological, economic, and societal endpoints and consequences that are sensitive to regional land-use/land-cover (LULC) change. The EPM uses both economics (monetized) and multiattribute utility (nonmonetized) approaches to valuing these endpoints and consequences. This hybrid approach represents a methodological middle ground between rigorous economic and ecological/ environmental scientific approaches. The EPM sacrifices some degree of economic- and ecological-forecasting precision to gain methodological transparency, spatial explicitness, and transferability, while maintaining credibility. After all, even small steps in the direction of including ecosystem services evaluation are an improvement over current land-use planning practice (Boyd and Wainger, 2003). There are many participants involved in land-use decision-making in South Florida, including local, regional, State, and Federal agencies, developers, environmental groups, agricultural groups, and other stakeholders (South Florida Regional Planning Council, 2003, 2004). The EPM's multicriteria evaluation framework is designed to cut across the objectives and knowledge bases of all of these participants. This approach places fundamental importance on social equity and stakeholder participation in land-use decision-making, but makes no attempt to determine normative socially 'optimal' land-use plans. The EPM is thus a map-based set of evaluation tools for planners and stakeholders to use in their deliberations of what is 'best', considering a balancing of disparate interests within a regional perspective. Although issues of regional ecological sustainability can be explored with the EPM (for example, changes in biodiversity potential and regional habitat fragmentation), it does not attempt to define or evaluate long-term ecological sustainability as such. Instead, the EPM is intended to provide transparent first-order indications of the direction of ecological, economic, and community change, not to make detailed predictions of ecological, economic, and social outcomes. In short, the EPM is an attempt to widen the perspectives of its users by integrating natural and social scientific information in a framework that recognizes the diversity of values at stake in South Florida land-use planning. For terrestrial ecosystems, land-cover change is one of the most important direct drivers of changes in ecosystem services (Hassan and others, 2005). More specifically, the fragmentation of habitat from expanding low-density development across landscapes appears to be a major driver of terrestrial species decline and the impairment of terrestrial ecosystem integrity, in some cases causing irreversible impairment from a land-use planning perspective (Brody, 2008; Peck, 1998). Many resource managers and land-use planners have come to realize that evaluating land-use conversions on a parcel-by-parcel basis leads to a fragmented and narrow view of the regional effects of natural land-cover loss to development (Marsh and Lallas, 1995). The EPM is an attempt to integrate important aspects of the coupled natural-system/human-system view from a regional planning perspective. The EPM evaluates proposed land-use changes, both conversion and intensification, in terms of relevant ecological, economic, and social criteria that combine information about probable land-use outcomes, based on ecological and environmental models, as well as value judgments, as expressed in user-modifiable preference models. Based on on-going meetings and interviews with stakeholders and potential tool users we foc

Scientific Investigations Report

Economic Growth and Landscape Change

Prato and Fagre offer the first systematic, multi-disciplinary assessment of the challenges involved in managing the Crown of the Continent Ecosystem (CCE), an area of the Rocky Mountains that includes northwestern Montana, southwestern Alberta, and southeastern British Columbia. The spectacular landscapes, extensive recreational options, and broad employment opportunities of the CCE have made it one of the fastest growing regions in the United States and Canada, and have lead to a shift in its economic base from extractive resource industries to service-oriented recreation and tourism industries. In the process, however, the amenities and attributes that draw people to this “New West” are under threat. Pastoral scenes are disappearing as agricultural lands and other open spaces are converted to residential uses, biodiversity is endangered by the fragmentation of fish and wildlife habitats, and many areas are experiencing a decline in air and water quality. Sustaining Rocky Mountain Landscapes provides a scientific basis for communities to develop policies for managing the growth and economic transformation of the CCE without sacrificing the quality of life and environment for which the land is renowned. This forthcoming edited volume focuses on five aspects of sustaining mountain landscapes in the CCE and similar regions in the Rocky Mountains. The five aspects are: 1) how social, economic, demographic and environmental forces are transforming ecosystem structure and function, 2) trends in use and conditions for human and environmental resources, 3) activating science, policy and education to enhance sustainable landscape management, 4) challenges to sustainable management of public and private lands, and 5) future prospects for achieving sustainable landscapes.

Book chapter

Adaptive harvest management for the Svalbard population of pink-footed geese (Anser brachyrhynchus)

This document describes progress to date on the development of an adaptive harvest-management strategy for maintaining the Svalbard population of pink-footed geese (Anser brachyrhynchus) near their target level (60,000) by providing for sustainable harvests in Norway and Denmark. Specifically, this report provides an assessment of the most recent monitoring information and its implications for the harvest management strategy. The development of an adaptive harvest management (AHM) strategy requires specification of four elements: (a) a set of alternative population models, which bound the uncertainty about effects of harvest and other relevant environmental factors; (b) a set of probabilities (or weights) describing the relative credibility of the alternative models, which are updated each year based on a comparison of model predictions and monitoring information; (c) a set of alternative harvest quotas from which to choose; and (d) a management objective function, by which alternative harvest strategies can be evaluated and a mathematically optimal strategy identified. By combining varying hypotheses about survival and reproduction, a suite of nine models were developed. Those models represent a wide range of possibilities concerning the extent to which demographic rates are density dependent, and the extent to which spring temperatures influence survival and reproduction. Five of the models incorporate density-dependent mechanisms that would maintain the population near a carrying capacity (i.e., in the absence of harvest) of 65,000 – 129,000 depending on the specific model. The remaining four models are density independent and predict an exponentially growing population even with moderate levels of harvest. The most current set of monitoring information was used to update model weights for the period 1991 – 2016. Current model weights suggest little evidence for density-dependent survival and reproduction. These results suggest that the pink-footed goose population may have recently experienced a release from density-dependent mechanisms, corresponding to the period of most rapid growth in population size. There is equivocal evidence for the effect of May temperature days in Svalbard (number of days with temperatures above freezing) on survival and reproduction. Beginning with the 2016 hunting season, harvest quotas are chosen on an annual basis rather than every three years because of the potential to better meet management objectives. The optimal harvest strategy, however, remains “knife-edged,” meaning that small changes in resource status can precipitate large changes in the annual harvest quota. This potential outcome is likely to be of concern to hunters, and we are investigating ways in which large swings in harvest quotas might be dampened. Based on updated model probabilities, the recent observations of record-high population size (88,000), the aboveaverage proportion of the population comprised of one-year-old birds (0.196), and temperature days in Svalbard (4), the suggested harvest quota for the 2017 hunting season is 36,000. Last year the quota was 25,000, yet a harvest of only 16,143 was realized. We are increasingly concerned that with the return of average spring temperatures in Svalbard, the population will continue to grow beyond managers’ ability to control it, as is the case with many goose populations in Europe and North America.

EGMP Technical Report

Sustaining Rocky Mountain landscapes: Science, policy and management for the Crown of the Continent ecosystem

Prato and Fagre offer the first systematic, multi-disciplinary assessment of the challenges involved in managing the Crown of the Continent Ecosystem ( CCE), an area of the Rocky Mountains that includes northwestern Montana, southwestern Alberta, and southeastern British Columbia. The spectacular landscapes, extensive recreational options, and broad employment opportunities of the CCE have made it one of the fastest growing regions in the United States and Canada, and have lead to a shift in its economic base from extractive resource industries to service-oriented recreation and tourism industries. In the process, however, the amenities and attributes that draw people to this “New West” are under threat. Pastoral scenes are disappearing as agricultural lands and other open spaces are converted to residential uses, biodiversity is endangered by the fragmentation of fish and wildlife habitats, and many areas are experiencing a decline in air and water quality. Sustaining Rocky Mountain Landscapes provides a scientific basis for communities to develop policies for managing the growth and economic transformation of the CCE without sacrificing the quality of life and environment for which the land is renowned. This forthcoming edited volume focuses on five aspects of sustaining mountain landscapes in the CCE and similar regions in the Rocky Mountains. The five aspects are: 1) how social, economic, demo graphic and environmental forces are transforming ecosystem structure and function, 2) trends in use and conditions for human and environmental resources, 3) activating science, policy and education to enhance sustainable landscape management, 4) challenges to sustainable management of public and private lands, and 5) future prospects for achieving sustainable landscapes.

Idaho, Montana

Assessing the sustainability of Pacific walrus harvest in a changing environment

Harvest sustainability is a primary goal of wildlife management and conservation, and in a changing world it is increasingly important to consider environmental drivers of population dynamics alongside harvest in cohesive management plans. This is particularly pertinent for harvested species that are acutely experiencing effects of climate change. The Pacific walrus ( Odobenus rosmarus divergens ), a critical traditional subsistence resource for indigenous communities, is simultaneously subject to rapid habitat loss associated with diminishing sea ice and an increasing anthropogenic footprint in the Arctic. We developed a theta-logistic population modeling-management framework to evaluate various harvest scenarios combined with four potential climate/disturbance scenarios (ranging from optimistic–pessimistic) which simulates Pacific walrus population dynamics to the end of the 21 st century. We considered two types of harvest strategies: (1) adaptive harvest scenarios wherein harvest is calculated as a percentage of the population and annual harvests are updated at set intervals as the population is reassessed, and (2) non-adaptive harvest scenarios wherein annual harvest remains constant. All climate/disturbance scenarios indicated declines of varying severity in Pacific walrus abundance to the end of the 21 st century, even in the absence of harvest. However, we found that an adaptive annual harvest of 1.23% of the independent-aged female subset of the population (e.g., 1,280 independent-aged females harvested in 2020, representing contemporary harvest levels) met our criterion for sustainability (>70% probability of maintaining population abundance above maximum net productivity level) under all climate/disturbance scenarios, accepting a medium risk tolerance level of 25%. This suggests that the present rate of Pacific walrus harvest is sustainable and will continue to be—provided the harvest adapts to match changes in population dynamics. Our simulations suggest that a sustainable non-adaptive harvest is also possible, but only at low levels if the population declines as expected. Applying a constant annual harvest of 1,280 independent-aged females (equivalent to contemporary harvest levels of 1.23) exceeded our criterion for sustainability and resulted in a >5% chance of quasi-extinction by the end of the 21 st century under three of the four climate/disturbance scenarios we evaluated. Our results highlight the importance of adaptive co-management strategies, and we suggest such modeling frameworks are useful for managing for harvest sustainability in a changing climate.

BioRxiv

Adaptive management in the U.S. National Wildlife Refuge System: Science-management partnerships for conservation delivery

Adaptive management is an approach to recurrent decision making in which uncertainty about the decision is reduced over time through comparison of outcomes predicted by competing models against observed values of those outcomes. The National Wildlife Refuge System (NWRS) of the U.S. Fish and Wildlife Service is a large land management program charged with making natural resource management decisions, which often are made under considerable uncertainty, severe operational constraints, and conditions that limit ability to precisely carry out actions as intended. The NWRS presents outstanding opportunities for the application of adaptive management, but also difficult challenges. We describe two cooperative programs between the Fish and Wildlife Service and the U.S. Geological Survey to implement adaptive management at scales ranging from small, single refuge applications to large, multi-refuge, multi-region projects. Our experience to date suggests three important attributes common to successful implementation: a vigorous multi-partner collaboration , practical and informative decision framework components , and a sustained commitment to the process. Administrators in both agencies should consider these attributes when developing programs to promote the use and acceptance of adaptive management in the NWRS.

Journal of Environmental Management

Recent advances in environmental flows science and water management—Innovation in the Anthropocene

The implementation of environmental flow regimes offers a promising means to protect and restore riverine, wetland and estuarine ecosystems, their critical environmental services and cultural/societal values. This Special Issue expands the scope of environmental flows and water science in theory and practice, offering 20 papers from academics, agency researchers and non‐governmental organisations, each with fresh perspectives on the science and management of environmental water allocations. Contributions confront the grand challenge for environmental flows and water management in the Anthropocene—the urgent need for innovations that will help to sustain the innate resilience of social–ecological systems under dynamic and uncertain environmental and societal futures. Basin‐scale and regional assessments of flow requirements mark a necessary advance in environmental water science in the face of rapid changes in water‐resource management activities worldwide (e.g. increases in dams, diversions, retention and reuse). Techniques for regional‐scale hydrological and ecohydrological modelling support ecological risk assessment and identification of priority flow management and river restoration actions. Changing flood–drought cycles, long‐term climatic shifts and associated effects on hydrological, thermal and water quality regimes add enormous uncertainty to the prediction of future ecological outcomes, regardless of environmental water allocations. An improved capacity to predict the trajectories of ecological change in rivers degraded by legacies of past impact interacting with current conditions and future climate change is essential. Otherwise, we risk unrealistic expectations from restoration of river and estuarine flow regimes. A more robust, dynamic and predictive approach to environmental water science is emerging. It encourages the measurement of process rates (e.g. birth rate, colonisation rate) and species traits (e.g. physiological requirements, morphological adaptations) as well as ecosystem states (e.g. species richness, assemblage structure), as the variables representing ecological responses to flow variability and environmental water allocations. Another necessary development is the incorporation of other environmental variables such as water temperature and sedimentary processes in flow–ecological response models. Based on contributions to this Special Issue, several recent compilations and the wider literature, we identify six major scientific challenges for further exploration, and seven themes for advancing the management of environmental water. We see the emerging frontier of environmental flows and water science as urgent and challenging, with numerous opportunities for reinvigorated science and methodological innovation in the expanding enterprise of environmental water linked to ecological sustainability and social well‐being.

Freshwater Biology

Defining ecosystem assets for natural capital accounting

In natural capital accounting, ecosystems are assets that provide ecosystem services to people. Assets can be measured using both physical and monetary units. In the international System of Environmental-Economic Accounting, ecosystem assets are generally valued on the basis of the net present value of the expected flow of ecosystem services. In this paper we argue that several additional conceptualisations of ecosystem assets are needed to understand ecosystems as assets, in support of ecosystem assessments, ecosystem accounting and ecosystem management. In particular, we define ecosystems’ capacity and capability to supply ecosystem services, as well as the potential supply of ecosystem services. Capacity relates to sustainable use levels of multiple ecosystem services, capability involves prioritising the use of one ecosystem service over a basket of services, and potential supply considers the ability of ecosystems to generate services regardless of demand for these services. We ground our definitions in the ecosystem services and accounting literature, and illustrate and compare the concepts of flow, capacity, capability, and potential supply with a range of conceptual and real-world examples drawn from case studies in Europe and North America. Our paper contributes to the development of measurement frameworks for natural capital to support environmental accounting and other assessment frameworks.

PLoS ONE

An integrated monitoring approach using multiple reference sites to assess sustainable restoration in coastal Louisiana

Achieving sustainable resource management in coastal Louisiana requires establishing reference conditions that incorporate the goals and objectives of restoration efforts. Since the reference condition is usually considered sustainable, it can be a gauge to assess the present condition of a (degraded) system or to evaluate progress of management actions toward some target system state (the reference or desired conditions). In 2003, the Coastal Wetlands Planning, Protection, and Restoration Act (CWPPRA) Task Force and the Louisiana State Wetlands Authority adopted the “Coastwide Reference Monitoring System -- Wetlands” (CRMS--Wetlands) for Louisiana. This system will provide data from multiple reference sites to explore the properties of a sustained reference condition. CRMS--Wetlands provides links between project-specific and system-wide objectives, criteria for selecting reference sites or conditions, a more robust statistical design, and critical monitoring variables. In addition, a system-wide assessment and monitoring plan (SWAMP) is being developed that incorporates and evaluates existing monitoring efforts (to the extent possible) within a system-wide experimental design. The SWAMP will integrate monitoring of biological, chemical, physical, and climatological variables in four modules: wetlands (CRMS--Wetlands), barrier islands, inshore waters and rivers, and nearshore coastal waters. Data and information collected under SWAMP will contribute to developing a systems-synthesis model for coastal Louisiana. Regional restoration project leaders in coastal Louisiana acknowledge the mutual dependence of monitoring and modeling the coastal landscape. For example, experiments or measurements should not be conducted independently of modeling and vice versa. Assessment should be directed at reducing scientific uncertainty to improve confidence in modeling and monitoring tools and ultimately to assist management actions. An adaptive environmental assessment and management process prescribes modeling, monitoring, and research activities to be conducted from initial stages of restoration planning to optimize the ability to assess and achieve sustainable restoration.

Louisiana