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At least 343 records · Page 19Linked to original sources
USGS2019

Regional protocol framework for the inventory and monitoring of breeding Atlantic Coast Piping Plovers

This regional protocol provides a framework for quantifying the number of breeding pairs and productivity of Atlantic Coast piping plover (Charadrius melodus) populations during the breeding season. A primary purpose of this protocol is to standardize piping plover monitoring during the breeding season. The survey techniques described herein involve repeated visual counts of adults, nests, eggs, and chicks within a defined survey site (i.e., beach) as well as visual identification of potential threats to survival and productivity. Resulting data can be compiled and analyzed across multiple geographic units (i.e., sites, states, and recovery units) to assess progress toward recovery goals, inform local management decisions, assess management effectiveness, and improve monitoring efforts. This protocol framework was developed as part of the United States Fish and Wildlife Service (USFWS) National Wildlife Refuge System (NWRS) Inventory and Monitoring (I&M) Initiative in coordination with Ecological Services (ES) and state coordinators within the Southeast and Northeast Regions (4 and 5, respectively). Although this protocol framework is to be used primarily by NWRS to inform recovery goals, assist with local management decision-making, and meet State reporting requirements, the approach strives to assist monitoring efforts of nonNWRS partners, such as other federal agencies (e.g. National Park Service), State wildlife agencies, non-governmental organizations, and private landowners. This protocol framework and associated data management system (PIPLweb) aims to interface with existing data management and analysis tools (i.e., PIPLODES, NestStory, and PiperEx) to ensure that data collection is efficient and comparable across scales, and supports management decisions across partners. The content and structure of the protocol framework follows standards set forth in the USFWS’s How to Develop Survey Protocols: A Handbook (Version 1.0; 2013). The eight elements addressed include: introduction, sampling design, field methods, data management and analysis, reporting, personnel requirements and training, operational requirements, and references. A series of standard operating procedures (SOPs) provides greater detail on recommended methods and technical aspects of this protocol. Data entry, archival, and multi-scale analysis are handled through a secure web application (Plover Inventory and Productivity Library; PIPLweb) developed by the United States Geological Survey (USGS). When management activities and survey objectives are similar across management units, partners (Refuges, other federal agencies, State, NGOs, private) are encouraged to use this protocol framework to develop stepped-down site-specific survey protocols that include guidance for conducting on-the-ground monitoring and management plans.

Regional Protocol Framework↗
USGS2017

Streamflow alteration and habitat ramifications for a threatened fish species in the Central United States

In the Central United States, the Arkansas darter ( Etheostoma cragini ) is listed as a threatened fish species by the State of Kansas. Survival of the darter is threatened by loss of habitat caused by changing streamflow conditions, in particular flow depletion. Future management of darter populations and habitats requires an understanding of streamflow conditions and how those conditions may have changed over time in response to natural and anthropogenic factors. In Kansas, streamflow alteration was assessed at 9 U.S. Geological Survey streamgages in 6 priority basins with no pronounced long-term trends in precipitation. The assessment was based on a comparison of observed (O) and predicted expected (E) reference conditions for 29 flow metrics. The O/E results indicated a likely or possible diminished flow condition in 2 basins; the primary cause of which is groundwater-level declines resulting from groundwater pumping for irrigated agriculture. In these 2 basins, habitat characteristics adversely affected by flow depletion may include stream connectivity, pools, and water temperature. The other 4 basins were minimally affected, or unaffected, by flow depletion and therefore may provide the best opportunity for preservation of darter habitat. Through the O/E analysis, anthropogenic streamflow alteration was quantified and the results will enable better-informed decisions pertaining to the future management of darters in Kansas.

Kansas↗
USGS2025

Public, bottled, and private drinking water: Shared contaminant-mixture exposures and effects challenge

BACKGROUND: Humans are primary drivers of environmental contaminant exposures worldwide, including in drinking-water (DW). In the United States (US), point-of-use DW (POU DW) is supplied via private tapwater (TW, predominantly private wells), public-supply TW, and bottled water (BW). Differences in management, monitoring, and messaging and lack of directly intercomparable exposure data influence the actual and perceived quality and safety of different DW supplies and directly impact consumer decision making. OBJECTIVES: The purpose of this paper is to provide a meta-analysis (quantitative synthesis) of POU DW contaminant mixture exposures and corresponding potential human health effects of private-TW, public-TW, and BW by aggregating exposure results and harmonizing apical health benchmark weighted and bioactivity weighted effects predictions across previous studies by this research group. DISCUSSION: Simultaneous exposures to multiple inorganic and organic contaminants of known or suspected human-health concern are common across all three DW supplies, with substantial variability observed in each and no systematic difference in predicted cumulative risk between supply chains. Differences in contaminant or contaminant class exposures (e.g., trace metals, disinfection byproducts), with important implications for DW quality improvements, were observed and attributed to corresponding differences in regulation and compliance monitoring. CONCLUSION: The results indicate that human-health risks from contaminant exposures are common to and comparable in all three DW supplies, including BW. Importantly, this study’s target analytical coverage, which exceeds that currently feasible for water purveyors or homeowners, nevertheless is a substantial underestimation of the full breadth of contaminant mixtures in the environment and potentially present in DW. Thus, the results emphasize the need for improved understanding of the adverse human-health implications of long-term exposures to low level inorganic /organic contaminant mixtures across all three distribution pipelines and do not support commercial messaging of BW as a systematically safer alternative to public-TW. Regardless of the supply, increased engagement in source-water protection and drinking-water treatment, including consumer point of use treatment, is necessary to reduce risks associated with long-term DW contaminant exposures, especially in vulnerable populations, and to reduce environmental waste and plastics contamination.

Environment International↗
USGS2019

Serum iron analytes in healthy and diseased Florida manatees (Trichechus manatus latirostris)

Serum iron concentration is usually decreased in true iron deficiency and with inflammatory disease in man and domestic animals. Serum total iron binding capacity (TIBC) may be increased in true iron deficiency and decreased with inflammatory disease. This prospective study was designed to measure serum iron analytes in healthy free-ranging and housed Florida manatees (Trichechus manatus latirostris) of both sexes and various ages and to evaluate the effects of diseases common to manatees on these analytes. Blood samples were collected without anticoagulant from 137 healthy free-ranging manatees, 90 healthy housed manatees and 74 free-ranging diseased manatees, and serum was prepared by centrifugation. Serum iron concentration and unsaturated iron binding capacity were measured colourimetrically, and TIBC and percent transferrin saturation with iron were calculated. Serum amyloid A (SAA) was measured to assist in the health assessment of manatees and provide evidence of inflammation in diseased manatees. Based on the serum iron analytes, iron availability was lower in immature manatees compared with adults, and it was lower in housed manatees compared with free-ranging manatees. In contrast to other mammals studied, serum iron concentration was elevated rather than depressed in late pregnancy. Serum iron concentrations and transferrin saturation with iron percentages were significantly lower, and SAA concentrations were significantly higher, in diseased (ill and injured) manatees compared with healthy manatees. Serum iron concentration and transferrin saturation with iron values were negatively correlated with SAA concentrations, and manatees with the highest SAA concentrations had lower serum TIBC values. These findings indicate that inflammation is the major factor responsible for alterations in iron analytes in diseased manatees. Consequently, hypoferraemia may be used as supportive evidence of inflammatory disease in manatees (unless haemorrhage is also present). A decision threshold of ≤13.8 μmol/l was determined for hypoferraemia using receiver operating curve analysis. Based on studies in man and domestic animals, iron therapy is unnecessary for manatees with hypoferraemia associated with inflammation and has the potential for causing tissue damage and increased susceptibility to bacterial infections.

Florida↗
USGS2020

Harvest–release decisions in recreational fisheries

Most fishery regulations aim to control angler harvest. Yet, we lack a basic understanding of what actually determines the angler’s decision to harvest or release fish caught. We used XGBoost, a machine learning algorithm, to develop a predictive angler harvest–release model by taking advantage of an extensive recreational fishery data set (24 water bodies, 9 years, and 193 523 fish). We were able to successfully predict the harvest–release outcome for 99% of fish caught in the training data set and 96% of fish caught in the test data set. Unsuccessful predictions were mostly attributed to predicting harvest of fish that were released. Fish length was the most essential feature examined for predicting angler harvest. Other important predictive harvest–release features included the number of individuals of the same species caught, geographic location of an angler’s residence, distance traveled, and time spent fishing. The XGBoost algorithm was able to effectively predict the harvest–release decision and revealed hidden and intricate relationships that are often unaccounted for with classical analysis techniques. Exposing and accounting for these angler–fish intricacies is critical for fisheries conservation and management.

Nebraska↗
USGS1971

Reconnaissance of the Sturgeon River, a cold-water river in the northcentral part of Michigan's southern peninsula

The cold-water streams of the northern states provide unique recreational values to the American people (wilderness or semi-wilderness atmosphere, fast-water canoeing, trout fishing), but the expanding recreational needs must be balanced against the growing demand of water for public and industrial supplies, for irrigation, and for the dilution of sewage and other wastes. In order to make intelligent decisions regarding use and management of the water resources for recreation and other demands, analysis of the hydrologic factors related to recreational values is essential. The Sturgeon River north of Gaylord, one of the best brown trout streams in Michigan, is located in the north-central part of the southern peninsula of Michigan with headwaters just north of Gaylord. The Sturgeon flows northward, generally paralleling Interstate Highway 75. The West Branch of the Sturgeon, which joins the main stem at Wolverine, was not included in this study. Exits from Interstate 75 at Gaylord, Vanderbilt, Wolverine, and Indian River provide easy access to the Sturgeon. The recreational value of a river depends on the hydrologic characteristics of the river-the streamflow, water quality, and character of bed and banks. The purpose of this atlas is to describe these characteristics and to show how they relate to recreational uses. Much of the information presented here was derived from basic records of the U.S. Geological Survey's Water Resources Division. Additional information was obtained in a reconnaissance survey in May and June, 1966. The area of field study is limited to the channel, bed, and banks of the main stem from source to mouth. The study was made in cooperation with the Michigan Geological Survey, Gerald E. Eddy, Chief. Advice and assistance were also obtained from other sections of the Michigan Conservation Department. Sheet 1 of this atlas presents information on streamflow characteristics and water quality. Sheet 2 describes the physical characteristics of the stream channel and bed and banks, and shows how these physical characteristics relate to streamflow, water quality, and recreational use.

Michigan↗
USGS1972

Reconnaissance of the Manistee River, a cold-water river in the northwestern part of Michigan's Southern Peninsula

The cold-water streams of the northern states provide unique recreational values to the American people (wilderness or semi-wilderness atmosphere, fast-water canoeing, trout fishing), but expanding recreational needs must be balanced against the growing demand of water for public and industrial supplies, irrigation, and dilution of sewage and other wastes. In order to make intelligent decisions regarding use and management of water resources for recreation and other demands, an analysis of hydrologic factors related to recreation is essential. The Manistee River is one of Michigan's well-known trout streams-a stream having numerous public access sites and campgrounds. Upstream from Cameron Bridge (see location map) the Manistee is rated as a first-class trout stream but below Cameron Bridge the river is rated only as a fair trout stream by the Michigan Department of Natural Resources. As a Michigan canoe trail it is second only to the Au Sable River in popularity. Esthetically, the Manistee is one of Michigan's most attractive rivers, its waters flowing cool and clean, and around each bend a pleasant wilderness scene. This report deals with that part of the river upstream from State Highway M-66 at Smithville. Several hard-surface roads give access to the upper river as shown on the location map. Numerous dirt roads and trails give access to the river at intermediate points. The recreational values of the Manistee depend on its characteristics of streamflow, water quality, and bed and banks. This atlas describes these characteristics and shows how they relate to recreational use. Much of the information presented here was obtained from basic records of the U.S. Geological Survey's Water Resources Division. Additional information was obtained from field reconnaissance surveys in 1968 and 1969. The study was made in cooperation with the Michigan Geological Survey, Gerald E. Eddy, Chief. Assistance was also obtained from other sections of the Michigan Department of Natural Resources.

Michigan↗
USGS2012

Estimated probability of arsenic in groundwater from bedrock aquifers in New Hampshire, 2011

Probabilities of arsenic occurrence in groundwater from bedrock aquifers at concentrations of 1, 5, and 10 micrograms per liter (µg/L) were estimated during 2011 using multivariate logistic regression. These estimates were developed for use by the New Hampshire Environmental Public Health Tracking Program. About 39 percent of New Hampshire bedrock groundwater was identified as having at least a 50 percent chance of containing an arsenic concentration greater than or equal to 1 µg/L. This compares to about 7 percent of New Hampshire bedrock groundwater having at least a 50 percent chance of containing an arsenic concentration equaling or exceeding 5 µg/L and about 5 percent of the State having at least a 50 percent chance for its bedrock groundwater to contain concentrations at or above 10 µg/L. The southeastern counties of Merrimack, Strafford, Hillsborough, and Rockingham have the greatest potential for having arsenic concentrations above 5 and 10 µg/L in bedrock groundwater. Significant predictors of arsenic in groundwater from bedrock aquifers for all three thresholds analyzed included geologic, geochemical, land use, hydrologic, topographic, and demographic factors. Among the three thresholds evaluated, there were some differences in explanatory variables, but many variables were the same. More than 250 individual predictor variables were assembled for this study and tested as potential predictor variables for the models. More than 1,700 individual measurements of arsenic concentration from a combination of public and private water-supply wells served as the dependent (or predicted) variable in the models. The statewide maps generated by the probability models are not designed to predict arsenic concentration in any single well, but they are expected to provide useful information in areas of the State that currently contain little to no data on arsenic concentration. They also may aid in resource decision making, in determining potential risk for private wells, and in ecological-level analysis of disease outcomes. The approach for modeling arsenic in groundwater could also be applied to other environmental contaminants that have potential implications for human health, such as uranium, radon, fluoride, manganese, volatile organic compounds, nitrate, and bacteria.

New Hampshire↗
USGS2006

Planning for robust reserve networks using uncertainty analysis

Planning land-use for biodiversity conservation frequently involves computer-assisted reserve selection algorithms. Typically such algorithms operate on matrices of species presence?absence in sites, or on species-specific distributions of model predicted probabilities of occurrence in grid cells. There are practically always errors in input data?erroneous species presence?absence data, structural and parametric uncertainty in predictive habitat models, and lack of correspondence between temporal presence and long-run persistence. Despite these uncertainties, typical reserve selection methods proceed as if there is no uncertainty in the data or models. Having two conservation options of apparently equal biological value, one would prefer the option whose value is relatively insensitive to errors in planning inputs. In this work we show how uncertainty analysis for reserve planning can be implemented within a framework of information-gap decision theory, generating reserve designs that are robust to uncertainty. Consideration of uncertainty involves modifications to the typical objective functions used in reserve selection. Search for robust-optimal reserve structures can still be implemented via typical reserve selection optimization techniques, including stepwise heuristics, integer-programming and stochastic global search.

Ecological Modelling↗
USGS1990

Geographic information system as country-level development and monitoring tool, Senegal example

Geographic information systems (GIS) allow an investigator the capability to merge and analyze numerous types of country-level resource data. Hypothetical resource analysis applications in Senegal were conducted to illustrate the utility of a GIS for development planning and resource monitoring. Map and attribute data for soils, vegetation, population, infrastructure, and administrative units were merged to form a database within a GIS. Several models were implemented using a GIS to: analyze development potential for sustainable dryland agriculture; prioritize where agricultural development should occur based upon a regional food budget; and monitor dynamic events with remote sensing. The steps for implementing a GIS analysis are described and illustrated, and the use of a GIS for conducting an economic analysis is outlined. Using a GIS for analysis and display of results opens new methods of communication between resource scientists and decision makers. Analyses yielding country-wide map output and detailed statistical data for each level of administration provide the advantage of a single system that can serve a variety of users.

Conference Paper↗
USGS2001

Interactive visualization of vegetation dynamics

Satellite imagery provides a mechanism for observing seasonal dynamics of the landscape that have implications for near real-time monitoring of agriculture, forest, and range resources. This study illustrates a technique for visualizing timely information on key events during the growing season (e.g., onset, peak, duration, and end of growing season), as well as the status of the current growing season with respect to the recent historical average. Using time-series analysis of normalized difference vegetation index (NDVI) data from the advanced very high resolution radiometer (AVHRR) satellite sensor, seasonal dynamics can be derived. We have developed a set of Java-based visualization and analysis tools to make comparisons between the seasonal dynamics of the current year with those from the past twelve years. In addition, the visualization tools allow the user to query underlying databases such as land cover or administrative boundaries to analyze the seasonal dynamics of areas of their own interest. The Java-based tools (data exploration and visualization analysis or DEVA) use a Web-based client-server model for processing the data. The resulting visualization and analysis, available via the Internet, is of value to those responsible for land management decisions, resource allocation, and at-risk population targeting.

Conference Paper↗
USGS2016

Toward an integrated understanding of perceived biodiversity values and environmental conditions in a national park

In spatial planning and management of protected areas, increased priority is being given to research that integrates social and ecological data. However, public viewpoints of the benefits provided by ecosystems are not easily quantified and often implicitly folded into natural resource management decisions. Drawing on a spatially explicit participatory mapping exercise and a Social Values for Ecosystem Services (SolVES) analysis tool, the present study empirically examined and integrated social values for ecosystem services and environmental conditions within Channel Islands National Park, California. Specifically, a social value indicator of perceived biodiversity was examined using on-site survey data collected from a sample of people who visited the park. This information was modeled alongside eight environmental conditions including faunal species richness for six taxa, vegetation density, categories of marine and terrestrial land cover, and distance to features relevant for decision-makers. Results showed that biodiversity value points assigned to places by the pooled sample of respondents were widely and unevenly mapped, which reflected the belief that biodiversity was embodied to varying degrees by multiple locations in the park. Models generated for two survey subgroups defined by their self-reported knowledge of the Channels Islands revealed distinct spatial patterns of these perceived values. Specifically, respondents with high knowledge valued large spaces that were publicly inaccessible and unlikely to contain on-ground biodiversity, whereas respondents with low knowledge valued places that were experienced first-hand. Accessibility and infrastructure were also important considerations for anticipating how and where people valued the protected land and seascapes of Channel Islands National Park.

California↗
USGS2022

Assessment of fecal contamination sources to Alley Creek, Queens County, New York, August 2020–June 2021

Alley Creek, a tributary to Little Neck Bay in Queens County, New York, has been designated by the New York State Department of Environmental Conservation as impaired (Class I) for fecal coliform because of pollution from combined sewer overflow, including stormwater runoff. The U.S. Geological Survey, in cooperation with the New York City Department of Environmental Protection, conducted a 1-year study from August 2020 to June 2021 using microbial source tracking (MST) methods to assess potential host sources of fecal contamination (for example, human, canine, and waterfowl) from the following: three outfall sites, TI–025, TI–008, and TI–024; an artesian well (Q277) adjacent to Alley Creek; and natural waters within the Alley Creek watershed and Little Neck Bay. In addition to analyzing for MST markers, field measurements such as water temperature and specific conductance, samples for total suspended solids, and fecal indicator bacteria (FIB; enterococci and fecal coliform) were collected. Pharmaceutical compounds were also collected for analysis, and the results of sampling were compared spatially and temporally to help support management decisions related to mitigation of fecal sources to Alley Creek. Factors that could affect concentrations, including tidal conditions, seasonality, and weather conditions, also were assessed. A sediment resuspension laboratory experiment was designed to replicate tidal activity in Alley Creek using sediment collected in the sewers and on the shoreline, as well as water collected from Oakland Lake. These sediment samples were assessed to understand the relation between sediment resuspension and FIB in the water column. The human MST markers used for this study, Bacteroides HF183/BacR287, and crAssphage CPQ_056 and CPQ_064, were detected in most samples (27 of 28) collected at the three outfall sites along Alley Creek, whereas the canine marker BacCan was less prevalent (20 of 28 samples) but exhibited a pattern of relative concentrations similar to the human markers. The waterfowl MST GFD marker was detected in 7 of 28 samples collected at the three outfall sites. Human MST markers were not detected at Oakland Lake (which drains through a combined sewer line to Alley Creek at TI–008), indicating minimal or nonexistent influence of sewage contamination in the lake. Groundwater samples collected from Q277 did not contain any MST markers, and concentrations of fecal coliform were less than 10 colony forming units per 100 milliliters. Although FIB did not correlate well with total suspended solids for individual sample sets, samples collected following precipitation and high-turbidity events were typically found to have higher concentrations of FIB than dry-weather samples. Results from the pharmaceutical compounds analysis provided additional evidence for determining known and suspected human sources when coupled with MST markers. Together, the MST, pharmaceutical, and FIB data generated by this study, along with supplementary data such as locations of point sources, locations of wildlife populations, and tidal exchange data, may provide reliable information on source identification and transport mechanisms of fecal contamination to Alley Creek.

New York↗
USGS2001

. Ecological conceptual models: a framework and case study on ecosystem management for South Florida sustainability

The Everglades and South Florida ecosystems are the focus of national and international attention because of their current degraded and threatened state. Ecological risk assessment, sustainability and ecosystem and adaptive management principles and processes are being used nationally as a decision and policy framework for a variety of types of ecological assessments. The intent of this study is to demonstrate the application of these paradigms and principles at a regional scale. The effects-directed assessment approach used in this study consists of a retrospective, eco-epidemiological phase to determine the causes for the current conditions and a prospective predictive risk-based assessment using scenario analysis to evaluate future options. Embedded in these assessment phases is a process that begins with the identification of goals and societal preferences which are used to develop an integrated suite of risk-based and policy relevant conceptual models. Conceptual models are used to illustrate the linkages among management (societal) actions, environmental stressors, and societal/ecological effects, and provide the basis for developing and testing causal hypotheses. These models, developed for a variety of landscape units and their drivers, stressors, and endpoints, are used to formulate hypotheses to explain the current conditions. They are also used as the basis for structuring management scenarios and analyses to project the temporal and spatial magnitude of risk reduction and system recovery. Within the context of recovery, the conceptual models are used in the initial development of performance criteria for those stressors that are determined to be most important in shaping the landscape, and to guide the use of numerical models used to develop quantitative performance criteria in the scenario analysis. The results will be discussed within an ecosystem and adaptive management framework that provides the foundation for decision making.

Science of the Total Environment↗
USGS2024

Accounting for multiple uncertainties in a decision-support population viability assessment

Conservation and management decisions often must be made on strict timelines, based on the “best available information” regarding a species’ current and expected future status. Simulation models are valuable tools for predicting a species’ future status but must incorporate multiple types of uncertainty in order to provide a complete understanding of plausible outcomes. Here we present a population viability analysis for a data-deficient species proposed for protection under the U.S. Endangered Species Act, the alligator snapping turtle. We used a matrix population model to simulate population trajectories, incorporating both parametric uncertainty and temporal variation into demographic parameters. We used expert elicitation to generate modified survival rates in the presence of specific anthropogenic threats, for which empirical estimates were unavailable. Because uncertainty in the expert elicited values was of particular interest to decision makers, we constructed a set of simulation scenarios to evaluate the sensitivity of model conclusions to the accuracy of expert elicited parameters. Our model predicted steep population declines under all scenarios with anthropogenic threats, indicating that under- or overestimation by experts would not change the overall conclusion that populations would decline. An additional sensitivity analysis revealed that a parameter related to nest survival for which there was high disagreement among experts had a negligible effect on model outcome, while other parameters (e.g., the effect of poaching) had more influence. Our analyses demonstrate the use of an expert-parameterized decision-support population viability analysis that explicitly evaluates the effects of multiple sources of uncertainty on model predictions.

Alabama, Arkansas, Florida, Georgia, Louisiana, Mi↗
USGS2021

A watershed moment: Analysis of sub-basins refocuses the geography of turtle conservation across the globe

Conservation planners use a variety of decision-making tools, many of which require identifying and prioritizing spatial units based on their biodiversity and levels of imperilment. Turtles are highly imperiled, but present schemes for determining global priority areas are focused mostly on broad regional scales. We conduct the first global evaluation of turtle biodiversity and imperilment at a sub-basin level to identify geographically smaller areas of high conservation value, and compare with these existing prioritizations. We employed two spatial analyses—bivariate maps and local indicator of spatial association (LISA)—to identify and prioritize sub-basin clusters based on multiple biodiversity and conservation metrics in addition to species richness. Most high-priority sub-basin clusters were located along tropical and subtropical coastlines. A new area of global significance for turtle conservation was identified in southwest India. Many sub-basins of the Indomalayan Realm were clustered as high or intermediate priority, with large clusters of high-priority sub-basins also in tropical Australasia. Other high and intermediate priority sub-basin clusters were found in the Afrotropical, Neotropical, and Nearctic realms, often in previously recognized turtle biodiversity hotspots. Many conservation-priority sub-basins with high turtle-species richness and endemism are in lowland and coastal areas where endemics (some from ancient lineages) are imperiled in association with a high human footprint. Our findings reiterate the global significance of Asia as a key area of chelonian conservation need, while identifying focal areas across the globe where the need for targeted turtle conservation is especially great.

Biological Conservation↗
USGS2021

Extending the capture map concept to estimate discrete and risk-based streamflow depletion potential

A popular and contemporary use of numerical groundwater models is to estimate the discrete relation between groundwater extraction and surface-water/groundwater exchange. Previously, the concept of a “capture map” has been put forward as a means to effectively summarize this relation for decision-making consumption. While capture maps have enjoyed success in the environmental simulation industry, they are deterministic, ignoring uncertainty in the underlying model. Furthermore, capture maps are not typically calculated in a manner that facilitates analysis of varying combinations of extraction locations and/or reaches. That is, they are typically constructed with focus on a single reach or group of reaches. The former of these limitations is important for conveying risk to decision makers and stakeholders, while the latter is important for decision-making support related to surface-water management, where future foci may include reaches that were not the focus of the original capture analysis. Herein, we use the concept of a response matrix to generalize the theory of the capture-map approach to estimate spatially discrete streamflow depletion potential. We also use first-order, second-moment uncertainty estimation techniques with the concept of “risk shifting” to place capture maps and streamflow depletion potential in a stochastic, risk-based framework. Our approach is demonstrated for an integrated groundwater/surface-water model of the lower San Antonio River, Texas, USA.

Groundwater↗
USGS2019

Understanding conservation decisions of agriculture producers

Most land in the United States (US) is privately owned and used for agriculture. To address the effect of agriculture on wildlife, conservation professionals and organizations need to understand the land use decisions made by farmers and ranchers. We developed a tool for categorizing farmers and ranchers by their conservation land use values (LUVs) to understand how those values affect their land use motivations and resultant decisions. We defined land as the whole natural environment including soil, water, plants, fish, and wildlife. We used principal axis factoring and reliability analysis to identify statements representing human-centered values and nature-centered values of farmers and ranchers. We tested the validity of the combined statements with a survey of South Dakota’s private landowners (N = 4,000, [Jan through May 2016]) resulting in the LUV scale. Crossing the average scores on the human-centered and nature-centered statements identified 4 LUV types: humans first (20%), nature first (29%), interconnected (29%), and disconnected (22%). Analysis of variance and chi-square tests showed that, compared to the humans first and disconnected LUV types, the nature first and interconnected LUV types reported significantly greater importance of the following: most categories of types of wildlife in their land use decisions; conservation-related motivations for participating in a United States Farm Bill Conservation Program; conservation-related motivations for land use decisions; and participation in conservation-related behaviors. Conservation professionals and organizations may use the LUV scale to better understand landowners’ land use decisions to evaluate and inform conservation policy, programs, messaging, and improve conservation outcomes.

Journal of Wildlife Management↗