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At least 163 records · Page 9Linked to original sources

Prototypic automated continuous recreational water quality monitoring of nine Chicago beaches

Predictive empirical modeling is used in many locations worldwide as a rapid, alternative recreational water quality management tool to eliminate delayed notifications associated with traditional fecal indicator bacteria (FIB) culturing (referred to as the persistence model, PM) and to prevent errors in releasing swimming advisories. The goal of this study was to develop a fully automated water quality management system for multiple beaches using predictive empirical models (EM) and state-of-the-art technology. Many recent EMs rely on samples or data collected manually, which adds to analysis time and increases the burden to the beach manager. In this study, data from water quality buoys and weather stations were transmitted through cellular telemetry to a web hosting service. An executable program simultaneously retrieved and aggregated data for regression equations and calculated EM results each morning at 9:30 AM; results were transferred through RSS feed to a website, mapped to each beach, and received by the lifeguards to be posted at the beach. Models were initially developed for five beaches, but by the third year, 21 beaches were managed using refined and validated modeling systems. The adjusted R 2 of the regressions relating Escherichia coli to hydrometeorological variables for the EMs were greater than those for the PMs, and ranged from 0.220 to 0.390 (2011) and 0.103 to 0.381 (2012). Validation results in 2013 revealed reduced predictive capabilities; however, three of the originally modeled beaches showed improvement in 2013 compared to 2012. The EMs generally showed higher accuracy and specificity than those of the PMs, and sensitivity was low for both approaches. In 2012 EM accuracy was 70–97%; specificity, 71–100%; and sensitivity, 0–64% and in 2013 accuracy was 68–97%; specificity, 73–100%; and sensitivity 0–36%. Factors that may have affected model capabilities include instrument malfunction, non-point source inputs, and sparse calibration data. The modeling system developed is the most extensive, fully-automated system for recreational water quality developed to date. Key insights for refining and improving large-scale empirical models for beach management have been developed through this multi-year effort.

Illinois↗

Dynamic wildlife occupancy models using automated acoustic monitoring data

Automated acoustic monitoring of wildlife has been used to characterize populations of sound-producing species across large spatial scales. However, false negatives and false positives produced by automated detection systems can compromise the utility of these data for researchers and land managers, particularly for research programs endeavoring to describe colonization and extinction dynamics that inform land use decision-making. To investigate the suitability of automated acoustic monitoring for dynamic occurrence models, we simulated underlying occurrence dynamics, calling patterns, and the automated acoustic detection process for a hypothetical species under a range of scenarios. We investigated an automated species detection aggregation method that considered a suite of options for creating encounter histories. From these encounter histories, we generated parameter estimates and computed bias for occurrence, colonization, and extinction rates using a dynamic occupancy modeling framework that accounts for false positives via small amounts of manual confirmation. We were able to achieve relatively unbiased estimates for all three state parameters under all scenarios, even when the automated detection system was simulated to be poor, given particular encounter history aggregation choices. However, some encounter history aggregation choices resulted in unreliable estimates; we provide caveats for avoiding these scenarios. Given specific choices during the detection aggregation process, automated acoustic monitoring data may provide an effective means for tracking species occurrence, colonization, and extinction patterns through time, with the potential to inform adaptive management at multiple spatial scales.

Ecological Applications↗

Informal trail monitoring protocols: Denali National Park and Preserve. Final Report, October 2011

Managers at Alaska?s Denali National Park and Preserve (DENA) sponsored this research to assess and monitor visitor-created informal trails (ITs). DENA is located in south-central Alaska and managed as a six million acre wilderness park. This program of research was guided by the following objectives: (1) Investigate alternative methods for monitoring the spatial distribution, aggregate lineal extent, and tread conditions of informal (visitor-created) trails within the park. (2) In consultation with park staff, develop, pilot test, and refine cost-effective and scientifically defensible trail monitoring procedures that are fully integrated with the park?s Geographic Information System. (3) Prepare a technical report that compiles and presents research results and their management implications. This report presents the protocol development and field testing process, illustrates the types of data produced by their application, and provides guidance for their application and use. The protocols described provide managers with an efficient means to document and monitor IT conditions in settings ranging from pristine to intensively visited.

Report↗

Snake River Fall Chinook Salmon research and monitoring

In Chapter 1, we report on development and application of an integrated population model (IPM) for the natural-origin fall Chinook salmon population upstream of Lower Granite Dam. This year’s efforts represent the third update to the model. Initial efforts focused on generating juvenile and adult abundance estimates, with estimates of uncertainty, for informing the life-cycle model and estimating the effects of covariates on key demographic parameters. The goals of this year’s report are to 1) describe the modifications and advances made since the previous report, 2) to annually update and report the abundance estimates and other quantities used in the model, 3) to provide annual estimates of population parameters estimated by the IPM, and 4) to outline the next year’s tasks for advancing and/or applying the model. Since our last report on the life-cycle model, we have made a number of changes including: 1) incorporating jack abundance and age-structure data into the observation model, 2) changing smolt-to-adult survival (SAR) for subyearling and yearling to partial SARs that represent the joint probability surviving and entering the ocean at a given juvenile age, 3) combining age categories for rarely observed ages, 4) using scale data from unmarked fish to estimate age structure, and 5) generating composite life-cycle demographic parameters (cumulative capacity and productivity) from stage-specific parameters. We also generated juvenile abundance estimates, extended the model to include three additional brood years (1992– 2021), and ran the model to forecast returns to Lower Granite in 2022. For posterior medians of life stage-specific parameters, we estimated a mean productivity of 438 natural-origin juvenile recruits per female spawner, a capacity of 1.36 million juveniles, and a mean smolt-to-adult survival (SAR) of 1.2%. We detected strong density-dependent regulation, with juvenile recruits per spawner declining to about 50 juvenile recruits per female spawner at high spawner abundance. Across the entire life cycle, these stage-specific parameters resulted in a median cumulative intrinsic productivity of 1.93 adult female recruits per female spawner and a median equilibrium abundance of 2,851 female spawners (7,842 total spawners). Annual juvenile productivity varied from about 250–1,000 juveniles per spawner but displayed no temporal trends or patterns. For the three most recent brood years added to the model, recruits per spawner were higher than average but well within the range of uncertainty observed over the entire time series. In contrast to juvenile recruitment variability, SAR varied considerably among years and exhibited two periods of high survival (1996–2001 and 2007–2012) when SAR ranged from 2% to 6% and cumulative productivity ranged from 2 to 8 recruits per spawner. Partial SARs revealed that yearling outmigrants contributed substantially to the high SARs in the first high-survival period, but the second period was dominated by subyearlings. Yearlings contributed >30% to SAR in most years prior to 2007, and <30% since 2007. Our two-stage IPM provides a wealth of information about population dynamics affecting two key life-stage transitions (spawner to juvenile, and juvenile to spawner) centered on passage at Lower Granite Dam. By summarizing these stage-specific demographic parameters across the entire life cycle, this information will be useful for informing the recovery status of this threatened population. Whereas previous versions introduced hydrosystem and ocean covariates into the model, this phase of model development focused on solidifying the underlying model structure by introducing the concept of partial SARs and developing composite productivity and capacity as a function of underlying stage-specific parameters. Given this advancement, our next steps are to re-incorporate covariates into the model, specifically to understand how different factors affect partial SARs of subyearling and yearlings. Longer term model developments include:1) incorporating hatchery fish to explicitly estimate their survival as an alternative method for estimating natural-origin age composition, 2) expanding the model’s structure to include the three major spawning aggregates, 3) more explicitly modeling hydrosystem effects including transportation, and 4) using the model to assess retrospective and prospective management actions. In 2022, the U.S. Geological Survey (USGS) focused adult salmon survey efforts in the Snake River on deepwater redd searches and fish collection for parentage-based tagging (PBT) analyses. We use used a boat-mounted underwater video camera to count 99 deepwater redds at 16 of the 29 sites surveyed. Redd depths averaged 4.4 m. In conjunction with the Idaho Power Company, we collected genetic samples from 318 live fall Chinook salmon (Oncorhynchus tshawytscha) and 19 carcasses at 40 unique geographic locations that spanned 91 river kilometers. Eighty fish were collected at three sites (High Range [rkm 332.3], Dug Bar [rkm 315.4], and Three Creek [rkm 384.0]), which accounted for 23% of all collected fish in 2022. Most (333 fish) post-spawned salmon were collected from early to mid-November just after the peak of spawning. A summary of 2021 PBT results produced by the Idaho Power Company can be found in Appendix A.2. Beach seining and PIT tagging of subyearling fall Chinook salmon was conducted in Snake and Salmon rivers to obtain information on population metrics and growth as well as to provide data for ongoing life-cycle modeling. In the Snake River, we collected 7,496 subyearlings, tagged 4,139, and recaptured 502 (12.1%). Using 8-mm tags in 45–49-mm fish allowed us to represent an additional 25% of the juvenile population through PIT tagging beyond just using standard 9- and 12-mm tags. In the Salmon River, we captured 206 natural subyearlings with the majority (52%) of fish being captured at two sites: rkm 20 and 26. We tagged 145 subyearlings and recaptured 9 fish. Many of the subyearlings we tagged in the Snake River were detected passing Lower Granite Dam, but only 4 fish tagged in the Salmon River were detected. In total we detected 484 (11.3%) tagged fish at Lower Granite Dam, and detection rates varied by tag size and passage route. More subyearlings were detected passing via the removable spill weir (RSW) earlier in the season while more fish were detected passing through the juvenile fish bypass system (JBS) earlier in the season while more fish were detected passing via the removable spill weir (RSW) later in the season. In general, fish tagged with 12-mm PIT tags had higher detection rates than fish tagged with smaller tags. Survival to Lower Granite Dam was low and ranged from 0.22 to 0.36. Season-wide, growth of subyearlings was higher in the lower reach than in the upper reach of the Snake River.

Idaho, Oregon, Washington↗

Looking for love under the ice: Using passive acoustics to detect burbot (Lota lota: Gadidae) spawning activity

Burbot ( Lota lota : Gadidae) is a difficult species to manage effectively due to its preference for deep‐water habitats and under‐ice spawning behaviour, resulting in a poor understanding of its reproductive activity. However, the use of acoustic signalling by burbot as part of their mating system has recently been described and this behaviour may provide a means of investigating questions regarding the spatial and temporal distribution of spawning aggregations using passive acoustic monitoring. We used audio and video recording to confirm that burbot vocalise and that these vocalisations can be detected under field conditions as well as to characterise the relationship between burbot acoustic signalling and spawning behaviour. We also evaluated the feasibility of locating and monitoring burbot spawning aggregations in real time using passive acoustics. Burbot vocalisations were difficult to identify with only about 6% of the recordings containing calls being successfully identified as such in the field. Burbot vocalised more often between sundown and sunrise than during daylight hours. Calls recorded at night tended to be lower frequency, longer duration, and have lower bandwidth than those made during the day. Burbot vocalisations could not be recorded in conjunction with video recordings of spawning activity, indicating that burbot may not call during active spawning, but may use acoustic communication to signal the onset of reproductive readiness and to form pre‐spawning aggregations. While burbot calls were readily identifiable, observers had a difficult time identifying burbot calls in real time under field conditions. Passive acoustic monitoring demonstrates considerable potential as a management tool to locate burbot spawning grounds and identify periods of activity, but may not be an appropriate technique for monitoring spawning activity in real time.

British Columbia↗

Managing more than the mean: Using quantile regression to identify factors related to large elk groups

Summary Animal group size distributions are often right-skewed, whereby most groups are small, but most individuals occur in larger groups that may also disproportionately affect ecology and policy. In this case, examining covariates associated with upper quantiles of the group size distribution could facilitate better understanding and management of large animal groups. We studied wintering elk groups in Wyoming, where group sizes span several orders of magnitude, and issues of disease, predation and property damage are affected by larger group sizes. We used quantile regression to evaluate relationships between the group size distribution and variables of land use, habitat, elk density and wolf abundance to identify conditions important to larger elk groups. We recorded 1263 groups ranging from 1 to 1952 elk and found that across all quantiles of group size, group sizes were larger in open habitat and on private land, but the largest effect occurred between irrigated and non-irrigated land [e.g. the 90th quantile group size increased by 135 elk (95% CI = 42, 227) on irrigation]. Only upper quantile group sizes were positively related to broad-scale measures of elk density and wolf abundance. For wolf abundance, this effect was greater on elk groups found in open habitats and private land than those in closed habitats or public land. If we had limited our analysis to mean or median group sizes, we would not have detected these effects. Synthesis and applications . Our analysis of elk group size distributions using quantile regression suggests that private land, irrigation, open habitat, elk density and wolf abundance can affect large elk group sizes. Thus, to manage larger groups by removal or dispersal of individuals, we recommend incentivizing hunting on private land (particularly if irrigated) during the regular and late hunting seasons, promoting tolerance of wolves on private land (if elk aggregate in these areas to avoid wolves) and creating more winter range and varied habitats. Relationships to the variables of interest also differed by quantile, highlighting the importance of using quantile regression to examine response variables more completely to uncover relationships important to conservation and management.

Wyoming↗

Contemporary greater prairie-chicken habitat distribution change and landscape thresholds in Kansas

Grassland bird monitoring efforts continue to document population declines in the Great Plains, USA and there is limited understanding of how declines are associated with landscape changes over broad scales. Within Kansas, USA, surveys indicate the resident grassland obligate greater prairie-chicken ( Tympanuchus cupido ) declined during the past 30 years. Grassland loss has been cited as the main driver of the decline; however, other factors including pesticide application, woody encroachment, and anthropogenic vertical structures are likely attributable. To evaluate, we used a random forest modeling approach to compare grassland cover, woody cover, and pesticide use between occupied ( n = 5552) and “pseudoabsent” ( n = 11,223) greater prairie-chicken lek site locations from 1993 to 2020. Our best-supported variables were grassland within 5 km, woody cover within 800 m, and pesticide application within 5 km of lek locations. The model correctly predicted the use or absence of leks with 89.95% accuracy based on independent validation. Our analysis suggests that grasslands have become aggregated within a 5 km radius where woody encroachment is less pronounced in the Smoky Hills and Northern High Plains management units and therefore landscapes have become more favorable for greater prairie-chickens at this scale. In contrast, the Flint Hills management unit netted a 13% loss of greater prairie-chicken habitat coinciding with woody encroachment and increased pesticide use. For 2020, we predicted a further loss of functional habitat from the presence of wind turbines, power transmission lines, and oil and gas infrastructure using previous literature documenting scales of avoidance. Our results support hypotheses that grassland loss, woody encroachment, and pesticide use all present negative population consequences for greater prairie-chickens. Current trends may be altered with grassland conservation action that seeks to conserve grasslands with < 10% woody cover and minimal pesticide use.

Kansas↗

Pacific walrus coastal haulout database, 1852-2016— Background report

Walruses are large benthic predators that rest out of water between foraging bouts. Coastal &ldquo;haulouts&rdquo; (places where walruses rest) are formed by adult males in summer and sometimes by females and young when sea ice is absent, and are often used repeatedly across seasons and years. Understanding the geography and historical use of haulouts provides a context for conservation efforts. We summarize information on Pacific walrus haulouts from available reports (n =151), interviews with coastal residents and aviators, and personal observations of the authors. We provide this in the form of a georeferenced database that can be queried and displayed with standard geographic information system and database management software. The database contains 150 records of Pacific walrus haulouts, with a summary of basic characteristics on maximum haulout aggregation size, age-sex composition, season of use, and decade of most recent use. Citations to reports are provided in the appendix and as a bibliographic database. Haulouts were distributed across the coasts of the Pacific walrus range; however, the largest (maximum >10,000 walruses) of the haulouts reported in the recent 4 decades (n=19) were concentrated on the Russian shores in regions near the Bering Strait and northward into the western Chukchi Sea (n=17). Haulouts of adult female and young walruses primarily occurred in the Bering Strait region and areas northward, with others occurring in the central Bering Sea, Gulf of Anadyr, and Saint Lawrence Island regions. The Gulf of Anadyr was the only region to contain female and young walrus haulouts, which formed after the northward spring migration and prior to autumn ice formation.

Alaska↗

Building a state-space life cycle model for naturally produced Snake River fall Chinook salmon

In 1992, Snake River basin fall Chinook salmon (Oncorhynchus tshawytscha) were listed for protection under the U.S. Endangered Species Act (NMFS 1992) and the population remained below 1000 individuals until 2000. Since then, returns from natural production has rebounded to over 20,000 spawners owing to a host of factors including reduced harvest (Peters et al. 2001), stable minimum spawning flows (Groves and Chandler 1999), summer flow augmentation (Connor et al. 2003), predator control (Beamesderfer et al. 1996), hatchery supplementation (Rosenberger et al. 2017), improved juvenile passage structures (Adams et al. 2014), summer spill operations (Perry et al. 2006; Adams et al. 2008), and periods of favorable ocean conditions and food availability (Logerwell et al. 2003; Peterson et al. 2014). Given this change in abundance coincident with numerous management actions and fluctuation in environmental drivers, quantifying which factors contributed to the observed rebound in natural production can provide critical insights into future management actions for this at-risk population. Multistage life cycle models provide a powerful analytical framework for understating how each life stage of a population contributes to population growth rate (Moussalli and Hilborn 1986; Greene and Beechie 2004). Multistage models may also be used as an analytical framework to explicitly estimate demographic parameters of a population model. This approach has an advantage over single-stage stock-recruitment models by allowing population growth rates to be partitioned among life stages rather than aggregated over an entire life cycle. Such partitioning allows for estimating 1) stage-specific density dependence, and 2) stage-specific effects of environmental factors or management actions. For example, Zabel et al. (2006) estimated parameters of a multistage model used in the context of a population viability analysis for spring/summer Chinook salmon in the Snake River, but such an approach has yet to be applied to fall Chinook salmon in the Snake River basin. Typically, data informing estimates of abundance at particular “check points” in the life cycle determines the complexity of the multistage model that can be fit to the data. For fall Chinook salmon, we are developing a two-stage model that encompasses: 1) upstream passage of spawners at Lower Granite Dam (LGR) to the subsequent downstream passage of their progeny at the dam, and 2) downstream passage of juveniles at LGR to their subsequent return from the ocean and passage at the Dam 2‒6 years later. This approach partitions the life cycle of fall Chinook salmon both spatially and temporally, which allows us to fit and compare alternative models with covariates specific to each stage. Our previous report to the ISAB (Zabel et al. 2013) detailed methods for estimating abundance of naturally produced adults and juveniles passing Lower Granite Dam, which provides the requisite data for fitting a two-stage model. The intent of this report is to describe the structure of the two-stage life cycle model, present preliminary results from fitting the model to data, and outline future directions and developments. As is clear from the diversity of models presented in this report, “life cycle models” range from very simple theoretically based population models (e.g., the Beverton-Holt stock- recruitment model) to very complex spatially explicit simulation models linked to hydrosystem hydrodynamic models (e.g., the COMPASS model for a single transition in a life cycle model, Zabel et al. 2008). We chose to develop a model of intermediate complexity that casts the two- stage life cycle model in a state-space framework (Newman et al. 2014). We chose to use a state-space framework implemented in a Bayesian framework because: • It provides both a statistical estimation framework for retrospective statistical analysis and a stochastic simulation framework for prospective analysis to evaluate alternative management actions. • Abundance estimates are uncertain. A state-space framework accounts for observation uncertainty in the abundance estimates and other data (e.g., age structure) while simultaneously estimating process uncertainty. • It allows for missing data. By drawing missing data from an appropriate probability model, uncertainty owing to missing data can be propagated without having to omit data or assume fixed values for missing data. Thus, a two-stage state-space life cycle model for fall Chinook salmon strikes an appropriate balance between model complexity, tractability, and applicability given the goals of performing both retrospective and prospective analysis to guide future management of this population.

Idaho, Oregon, Washington, Wyoming↗

Verification of irrigated agricultural land acreage in 55 counties in Florida, 2013–21

In 2012, the Florida Legislature mandated that the Florida Department of Agriculture and Consumer Services (FDACS), Office of Agricultural Water Policy, promote an agricultural water-conservation program that would include a cost-share program and best management practices and that would aid the five water management districts in the development of consistent agricultural water-supply planning, assisting the districts in projecting future agricultural water needs and promoting consistency in water-use estimates among the districts. Beginning in 2013, the FDACS created a series of agriculture and irrigated land-use maps for all Florida counties for the purpose of estimating current and forecasting future water demands. These maps, produced and updated periodically by The Balmoral Group, were based on baseline data from 2010 and have been updated with a combination of satellite images and land-use data from water management districts in subsequent years (2013–21) to help create a statewide database of irrigated agricultural lands. The purpose of this multiyear cooperative study between the U.S. Geological Survey and the FDACS is to provide (1) a detailed geospatial database of verified irrigated field locations with selected attributes as ArcGIS shapefiles and (2) aggregated acreage totals by crop type for all or parts of 55 of the 67 counties within Florida. Ten of the remaining 12 counties were fully mapped by the St. John’s River Water Management District in 2015; the other 2 counties were not mapped because they contained very little irrigated agricultural land. Irrigated agricultural fields identified on The Balmoral Group baseline maps for each of the 55 counties were either physically observed by U.S. Geological Survey or were verified through water management district’s consumptive water-use permit database. A select group of counties were chosen to be field verified each year, concluding with a total of 55 counties in Florida field verified between October 2013 and August 2021. The results provided from this multiyear study can help increase the accuracy of irrigation water-use estimates for counties in Florida.

Florida↗

Sequestration of carbon in soil organic matter in Senegal: an overview

Sequestration of Carbon in Soil Organic Matter ( SOCSOM ) in Senegal is a multi-disciplinary development project planned and refined through two international workshops. The project was implemented by integrating a core of international experts in remote sensing, biogeochemical modeling, community socio-economic assessments, and carbon measurements in a fully collaborative manner with Senegal organizations, national scientists, and local knowledge and expertise. The study addresses the potential role developing countries in semi-arid areas can play in climate mitigation activities. Multiple benefits to smallholders could accrue as a result of management practices to re-establish soil carbon content lost because of land use changes or management practices that are not sustainable. The specific importance for the Sahel is because of the high vulnerability to climate change in already impoverished rural societies. The project focuses on four objectives in specific locations across the agroecological zones of Senegal. These objectives are: use of soil sampling and biogeochemical modeling to quantify the biophysical potential for carbon sequestration and to determine the sensitivity of the carbon stocks to various management and climate scenarios, to evaluate the socio-economic and cultural requirements necessary for successful project implementation directed toward an aggregation of smallholders to sequester around 100,000 t carbon (C), to support capacity building to develop a Carbon Specialist Team, and to initiate extrapolation from site-specific project areas to the Sahel region and the national level.

Journal of Arid Environments↗

Georgia's Stream-Water-Quality Monitoring Network, 2006

The USGS stream-water-quality monitoring network for Georgia is an aggregation of smaller networks and individual monitoring stations that have been established in cooperation with Federal, State, and local agencies. These networks collectively provide data from 130 sites, 62 of which are monitored continuously in real time using specialized equipment that transmits these data via satellite to a centralized location for processing and storage. These data are made available on the Web in near real time at http://waterdata.usgs.gov/ga/nwis/ Ninety-eight stations are sampled periodically for a more extensive suite of chemical and biological constituents that require laboratory analysis. Both the continuous and the periodic water-quality data are archived and maintained in the USGS National Water Information System and are available to cooperators, water-resource managers, and the public. The map at right shows the USGS stream-water-quality monitoring network for Georgia and major watersheds. The network represents an aggregation of smaller networks and individual monitoring stations that collectively provide data from 130 sites.

Georgia↗

Classification systems for natural resource management

Resource managers employ various types of resource classification systems in their management activities such as inventory, mapping, and data analysis. Classification is the ordering or arranging of objects into groups or sets on the basis of their relationships, and as such, provide the resource managers with a structure for organizing their needed information. In addition of conforming to certain logical principles, resource classifications should be flexible, widely applicable to a variety of environmental conditions, and useable with minimal training. The process of classification may be approached from the bottom up (aggregation) or the top down (subdivision) or a combination of both, depending on the purpose of the classification. Most resource classification systems in use today focus on a single resource and are used for a single, limited purpose. However, resource managers now must employ the concept of multiple use in their management activities. What they need is an integrated, ecologically based approach to resource classification which would fulfill multiple-use mandates. In an effort to achieve resource-data compatibility and data sharing among Federal agencies, and interagency agreement has been signed by five Federal agencies to coordinate and cooperate in the area of resource classification and inventory.

Pecora VII Symposium↗

Cold blood in warming waters: Effects of air temperature, precipitation, and groundwater on Gulf Sturgeon thermal habitats in a changing climate

Objective In a changing climate, the effects of air temperature, precipitation, and groundwater on water temperature and thermal habitat suitability for Gulf Sturgeon Acipenser desotoi , listed as threatened under the U.S. Endangered Species Act, are not well understood. Hence, we incorporated these factors into thermal habitat models to forecast how Gulf Sturgeon may be affected by wide‐ranging climate change scenarios in 2024–2074. Methods Using data from the Choctawhatchee River, Florida, we developed precipitation‐ and groundwater‐corrected air–water temperature models, compared their accuracy with that of conventional air–water temperature models used in fisheries management, and projected future Gulf Sturgeon thermal habitat suitability for normal physiological functioning and fieldwork (i.e., population sampling and telemetry surgeries) in summer (May–August) under 16 climate change scenarios. Result Precipitation‐ and groundwater‐corrected models were more accurate than conventional air–water temperature models (mean improvement in adjusted R 2 = +0.45; range = +0.09 to +0.75). Water temperature was projected to warm at widely variable rates across climate change scenarios encompassing different air temperature, precipitation, and groundwater regimes. Importantly, Gulf Sturgeon summer aggregation areas were cooler and influenced more by precipitation and groundwater and less by air temperature than were non‐aggregation areas. If precipitation and groundwater—as drivers of cooling—become warm in a changing climate, summer aggregation areas were projected to exhibit thermal habitat degradation equivalent to or greater than that of non‐aggregation areas. Conclusion Our results add hydrological context to the premise that aggregation areas provide cool water and energetic savings for Gulf Sturgeon during summer, underscoring the importance of protecting these habitats through groundwater conservation, water quality monitoring, and riparian/watershed habitat management. Our findings indicate that identifying thermally appropriate times for fieldwork activities will be increasingly important and time‐restricted as climate change intensifies. However, our research provides managers with a portfolio of water temperature models and an accurate, cost‐effective, management‐relevant approach to forecasting thermal habitat conditions for Gulf Sturgeon and other species in a changing climate.

Alabama, Florida↗

Estimating the social and economic consequences of proposed management alternatives at the National Elk Refuge

The National Elk Refuge (Refuge) is managed by the U.S. Fish and Wildlife Service and includes habitats for bison and elk. Bison and elk provide opportunities for wildlife-related recreation and contribute to the tourism industry in and around Jackson, Wyoming. Over the last century, the Refuge has provisioned supplemental feed to elk and, more recently, bison during winter months to ensure adequate forage and prevent starvation and conflict with private landowners. However, supplemental feeding artificially aggregates animals and can increase rates of disease transmission and localized damage to sensitive habitats near the feeding areas. This report presents analyses and results to support two of the nine management objectives in the next “Bison and Elk Management Plan,” with a particular focus on the social and economic consequences of five management alternatives considered in this study. The alternatives are to continue feeding bison and elk during winter months on the Refuge, stop feeding after CWD is measured at 3 percent prevalence or above in the Jackson elk herd, stop feeding immediately, reduce feeding for five years and then stop feeding, and increase elk harvest for five years and then stop feeding. These alternatives are anticipated to alter bison and elk population and space-use dynamics, with corresponding effects on wildlife-related recreation and tourism, including the number of visitors and sleigh-ride participants on the Refuge, and hunters and outfitters within the Jackson Elk Herd Unit. The performance of each of this study’s alternatives was variable, resulting in overlap in the performance of alternatives on the select objectives over the next 20 years. Generally, visitation-related objectives performed better under the continue feeding alternative, whereas hunting-related objectives performed better under the increase harvest alternative. The results presented here may assist U.S. Fish and Wildlife Service decision makers in balancing social and economic benefits identified in the decision-making process for the “Bison and Elk Management Plan” with other objectives evaluated in this report.

Wyoming↗

Estimating the social and economic consequences of proposed management alternatives at the National Elk Refuge in Jackson, Wyoming

The National Elk Refuge (Refuge) is managed by the U.S. Fish and Wildlife Service and includes habitats for bison and elk. Bison and elk provide opportunities for wildlife-related recreation and contribute to the tourism industry in and around Jackson, Wyoming. Over the last century, the Refuge has provisioned supplemental feed to elk and, more recently, bison during winter months to ensure adequate forage and prevent starvation and conflict with private landowners. However, supplemental feeding artificially aggregates animals and can increase rates of disease transmission and localized damage to sensitive habitats near the feeding areas. This report presents analyses and results to support two of the nine management objectives in the next “Bison and Elk Management Plan,” with a particular focus on the social and economic consequences of five management alternatives considered in this study. The alternatives are to continue feeding bison and elk during winter months on the Refuge, stop feeding after CWD is measured at 3 percent prevalence or above in the Jackson elk herd, stop feeding immediately, reduce feeding for five years and then stop feeding, and increase elk harvest for five years and then stop feeding. These alternatives are anticipated to alter bison and elk population and space-use dynamics, with corresponding effects on wildlife-related recreation and tourism, including the number of visitors and sleigh-ride participants on the Refuge, and hunters and outfitters within the Jackson Elk Herd Unit. The performance of each of this study’s alternatives was variable, resulting in overlap in the performance of alternatives on the select objectives over the next 20 years. Generally, visitation-related objectives performed better under the continue feeding alternative, whereas hunting-related objectives performed better under the increase harvest alternative. The results presented here may assist U.S. Fish and Wildlife Service decision makers in balancing social and economic benefits identified in the decision-making process for the “Bison and Elk Management Plan” with other objectives evaluated in this report.

Wyoming↗

Management and analysis of water-use data using a geographic information system

As part of its mission, the U.S. Geological Survey conducts water-resources research. Site-specific and aggregate water-use data are used in the Survey's National Water-Use Information Program and in various hydrologic investigations. Both types of activities have specific requirements in terms of water-use data access, analysis, and display. In Kansas, the Survey obtains water-use information from several sources. Typically, this information is in a format that is not readily usable by the Survey. Geographic information system (GIS) technology is being used to restructure the available water-use data into a format that allows users to readily access and summarize site-specific water-use data by source (i.e., surface or ground water), type of use, and user-defined area.

Water Resources Bulletin↗

Effects of supplemental feeding and aggregation on fecal glucocorticoid metabolite concentrations in elk

Habitat modifications and supplemental feeding artificially aggregate some wildlife populations, with potential impacts upon contact and parasite transmission rates. Less well recognized, however, is how increased aggregation may affect wildlife physiology. Crowding has been shown to induce stress responses, and increased glucocorticoid (GC) concentrations can reduce immune function and increase disease susceptibility. We investigated the effects of supplemental feeding and the aggregation that it induces on behavior and fecal glucocorticoid metabolite concentrations (fGCM) in elk (Cervus elaphus) using observational and experimental approaches. We first compared fGCM levels of elk on supplemental feedgrounds to neighboring elk populations wintering in native habitats using data from 2003 to 2008. We then experimentally manipulated the distribution of supplemental food on feedgrounds to investigate whether more widely distributed food would result in lower rates of aggression and stress hormone levels. Contrary to some expectations that fed elk may be less stressed than unfed elk during the winter, we found that elk on feedgrounds had fecal GC levels at least 31% higher than non-feedground populations. Within feedgrounds, fGCM levels were strongly correlated with local measures of elk density (r 2 = 0.81). Dispersing feed more broadly, however, did not have a detectable effect on fGCM levels or aggression rates. Our results suggest that increases in aggregation associated with winter feedgrounds affects elk physiology, and the resulting increases in fGCM levels are not likely to be mitigated by management efforts that distribute the feed more widely. Additional research is needed to assess whether these increases in fGCMs directly alter parasite transmission and disease dynamics.

Journal of Wildlife Management↗