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USGS2021

Bridging the research-implementation gap in avian conservation with translational ecology

The recognized gap between research and implementation in avian conservation can be overcome with translational ecology, an intentional approach in which science producers and users from multiple disciplines work collaboratively to co-develop and deliver ecological research that addresses management and conservation issues. Avian conservation naturally lends itself to translational ecology because birds are well studied, typically widespread, often exhibit migratory behaviors transcending geopolitical boundaries, and necessitate coordinated conservation efforts to accommodate resource and habitat needs across the full annual cycle. In this perspective, we highlight several case studies from bird conservation practitioners and the ornithological and conservation social sciences exemplifying the 6 core translational ecology principles introduced in previous studies: collaboration, engagement, commitment, communication, process, and decision-framing. We demonstrate that following translational approaches can lead to improved conservation decision-making and delivery of outcomes via co-development of research and products that are accessible to broader audiences and applicable to specific management decisions (e.g., policy briefs and decision-support tools). We also identify key challenges faced during scientific producer–user engagement, potential tactics for overcoming these challenges, and lessons learned for overcoming the research-implementation gap. Finally, we recommend strategies for building a stronger translational ecology culture to further improve the integration of these principles into avian conservation decisions. By embracing translational ecology, avian conservationists and ornithologists can be well positioned to ensure that future management decisions are scientifically informed and that scientific research is sufficiently relevant to managers. Ultimately, such teamwork can help close the research-implementation gap in the conservation sciences during a time when environmental issues are threatening avian communities and their habitats at exceptional rates and at broadening spatial scales worldwide.

Ornithological Applications↗
USGS2023

Influence of fine-scale habitat characteristics on sage-grouse nest site selection and nest survival varies by mesic and xeric site conditions

Resource managers and scientists across western U.S. agencies seek methodologies for identifying environmental attributes important to both wildlife conservation and broad-scale land stewardship. The Greater Sage-Grouse ( Centrocercus urophasianus ; hereafter, sage-grouse) exemplifies a species in need of this broad-scale approach given widespread population declines that have resulted from loss and degradation of habitat from natural and anthropogenic disturbances. These include agricultural land conversion, conifer expansion, energy development, and wildfire coupled with ecological conversion by invasive plants such as cheatgrass ( Bromus tectorum ). Development of habitat assessments and conservation actions for sage-grouse benefit from studies that link demographic responses to habitat selection patterns. To address this, we examined nest survival of sage-grouse in relation to fine-scale habitat patterns (i.e., field-based habitat measurements) that influenced nest site selection, using data from nests of telemetered females at 17 sites over 6 years in Nevada and northeastern California, USA. Importantly, sites spanned mesic and xeric average precipitation conditions that contributed substantially to vegetation community structure across cold desert ecosystems of the North American Great Basin. Vegetative cover immediately surrounding sage-grouse nests was important for both nest site selection and nest survival, but responses varied between mesic and xeric sites. For example, while taller perennial grasses were selected at xeric sites, we found no evidence of selection for perennial grass at mesic sites, indicating a functional response to availability of habitat features between hydrographic regions. Furthermore, perennial grass height and forb height both had positive effects on nest survival at xeric sites, but we found varying effects at mesic sites. We emphasize that precipitation conditions driving ecosystem productivity vary regionally among sagebrush communities, shaping vegetation structure and suitable habitat conditions for nesting sage-grouse.

Ornithological Applications↗
USGS2010

Standards for documenting and monitoring bird reintroduction projects

It would be much easier to assess the effectiveness of different reintroduction methods, and so improve the success of reintroductions, if there was greater standardization in documentation of the methods and outcomes. We suggest a series of standards for documenting and monitoring the methods and outcomes associated with reintroduction projects for birds. Key suggestions are: documenting the planned release before it occurs, specifying the information required on each release, postrelease monitoring occurring at standard intervals of 1 and 5 years (and 10 for long-lived species), carrying out a population estimate unless impractical, distinguishing restocked and existing individuals when supplementing populations, and documenting the results. We suggest these principles would apply, largely unchanged, to other vertebrate classes. Similar methods could be adopted for invertebrates and plants with appropriate modification. We suggest that organizations publicly state whether they will adopt these approaches when undertaking reintroductions. Similar standardization would be beneficial for a wide range of topics in environmental monitoring, ecological studies, and practical conservation.

Conservation Letters↗
USGS2017

Effects of native herbs and light on garlic mustard ( Alliaria petiolata ) invasion

The degree to which invasive species drive or respond to environmental change has important implications for conservation and invasion management. Often characterized as a driver of change in North American woodlands, the invasive herb garlic mustard may instead respond to declines in native plant cover and diversity. We tested effects of native herb cover, richness, and light availability on garlic mustard invasion in a Minnesota oak woodland. We planted 50 garlic mustard seeds into plots previously planted with 0 to 10 native herb species. We measured garlic mustard seedling establishment, survival to rosette and adult stages, and average (per plant) and total (per plot) biomass and silique production. With the use of structural equation models, we analyzed direct, indirect, and net effects of native cover, richness, and light on successive garlic mustard life stages. Native plant cover had a significant negative effect on all life stages. Species richness had a significant positive effect on native cover, resulting in indirect negative effects on all garlic mustard stages, and net negative effects on adult numbers, total biomass, and silique production. Light had a strong negative effect on garlic mustard seedling establishment and a positive effect on native herb cover, resulting in significant negative net effects on garlic mustard rosette and adult numbers. However, light's net effect on total garlic mustard biomass and silique production was positive; reproductive output was high even in low-light/high-cover conditions. Combined effects of cover, richness, and light suggest that native herbs provide biotic resistance to invasion by responding to increased light availability and suppressing garlic mustard responses, although this resistance may be overwhelmed by high propagule pressure. Garlic mustard invasion may occur, in part, in response to native plant decline. Restoring native herbs and controlling garlic mustard seed production may effectively reduce garlic mustard spread and restore woodland diversity.

Invasive Plant Science and Management↗
USGS1978

Nebraska water data programs for 1978

Projects of the Water Resources Division, U.S. Geological Survey, and of State agencies represented by members of the Nebraska Water Data Coordinating Committee are described. The committee members represent the Nebraska Department of Water Resources, Nebraska Department of Environmental Control, Nebraska Department of Health, Conservation and Survey Division of the University of Nebraska-Lincoln, Nebraska Water Resources Center of the University of Nebraska, Nebraska Natural Resources Commission, and Nebraska Game and Parks Commission. Current measuring sites are listed. Indexes to streamflow records and flood-prone area maps and a list of recently published reports also are included. Sources of water-related information are given with names, addresses, and telephone numbers.

Nebraska↗
USGS2011

Factors influencing riverine fish assemblages in Massachusetts

The U.S. Geological Survey, in cooperation with the Massachusetts Department of Conservation and Recreation, Massachusetts Department of Environmental Protection, and the Massachusetts Department of Fish and Game, conducted an investigation of fish assemblages in small- to medium-sized Massachusetts streams. The objective of this study was to determine relations between fish-assemblage characteristics and anthropogenic factors, including impervious cover and estimated flow alteration, relative to the effects of environmental factors, including physical-basin characteristics and land use. The results of this investigation supersede those of a preliminary analysis published in 2010. Fish data were obtained for 669 fish-sampling sites from the Massachusetts Division of Fisheries and Wildlife fish-community database. A review of the literature was used to select fish metrics - species richness, abundance of individual species, and abundances of species grouped on life history traits - responsive to flow alteration. The contributing areas to the fish-sampling sites were delineated and used with a geographic information system to determine a set of environmental and anthropogenic factors that were tested for use as explanatory variables in regression models. Reported and estimated withdrawals and return flows were used together with simulated unaltered streamflows to estimate altered streamflows and indicators of flow alteration for each fish-sampling site. Altered streamflows and indicators of flow alteration were calculated on the basis of methods developed in a previous U.S. Geological Survey study in which unaltered daily streamflows were simulated for a 44-year period (water years 1961-2004), and streamflow alterations were estimated by use of water-withdrawal and wastewater-return data previously reported to the State for the 2000-04 period and estimated domestic-well withdrawals and septic-system discharges. A variable selection process, conducted using principal components analysis and Spearman rank correlation, was used to select a set of 15 non-redundant environmental and anthropogenic factors to test for use as explanatory variables in the regression analyses. Twenty-one fish species were used in a multivariate analysis of fish-assemblage patterns. Results of nonmetric multidimensional scaling and hierarchical cluster analysis were used to group fish species into fluvial and macrohabitat generalist habitat-use classes. Two analytical techniques, quantile regression and generalized linear modeling, were applied to characterize the association between fish-response variables and environmental and anthropogenic explanatory variables. Quantile regression demonstrated that as percent impervious cover and an indicator of percent alteration of August median flow from groundwater withdrawals increase, the relative abundance and species richness of fluvial fish decrease. The quantile regression plots indicate that (1) as many as seven fluvial fish species are expected in streams with little flow alteration or impervious cover, (2) no more than four fluvial fish species are expected in streams where flow alterations from groundwater withdrawals exceed 50 percent of the August median flow or the percent area of impervious cover exceeds 15 percent, and (3) few fluvial fish remain at high rates of withdrawal (approaching 100 percent) or high rates of impervious cover (between 25 and 30 percent). Three generalized linear models (GLMs) were developed to quantify the response of fluvial fish to multiple environmental and anthropogenic variables. All variables in the GLM equations were demonstrated to be significant (p less than 0.05, with most less than 0.01). Variables in the fluvial-fish relative-abundance model were channel slope, estimated percent alteration of August median flow from groundwater withdrawals, percent wetland in a 240-meter buffer strip, and percent impervious cover. Variables in the fluvial-fish species-richness model were drainage area, channel slope, total undammed reach length, percent wetland in a 240-meter buffer strip, and percent impervious cover. Variables in the brook trout relativeabundance model were drainage area, percent open water, and percent impervious cover. The variability explained by the GLM models, as measured by the pseudo R2, ranged from 18.2 to 34.6, and correlations between observed and predicted values ranged from 0.50 to 0.60. Results of GLM models indicated that, keeping all other variables the same, a one-unit (1 percent) increase in the percent depletion of August median flow would result in a 0.9-percent decrease in the relative abundance (in counts per hour) of fluvial fish. The results of GLM models also indicated that a unit increase in impervious cover (1 percent) resulted in a 3.7-percent decrease in the relative abundance of fluvial fish, a 5.4-percent decrease in fluvial-fish species richness, and an 8.7-percent decrease in brook trout relative abundance.

Massachusetts↗
USGS2016

Montana StreamStats

About this volume Montana StreamStats is a Web-based geographic information system ( http://water.usgs.gov/osw/streamstats/ ) application that provides users with access to basin and streamflow characteristics for gaged and ungaged streams in Montana. Montana StreamStats was developed by the U.S. Geological Survey (USGS) in cooperation with the Montana Departments of Transportation, Environmental Quality, and Natural Resources and Conservation. The USGS Scientific Investigations Report consists of seven independent but complementary chapters dealing with various aspects of this effort. Chapter A describes the Montana StreamStats application, the basin and streamflow datasets, and provides a brief overview of the streamflow characteristics and regression equations used in the study. Chapters B through E document the datasets, methods, and results of analyses to determine streamflow characteristics, such as peak-flow frequencies, low-flow frequencies, and monthly and annual characteristics, for USGS streamflow-gaging stations in and near Montana. The StreamStats analytical toolsets that allow users to delineate drainage basins and solve regression equations to estimate streamflow characteristics at ungaged sites in Montana are described in Chapters F and G.

Montana↗
USGS2015

Water-budgets and recharge-area simulations for the Spring Creek and Nittany Creek Basins and parts of the Spruce Creek Basin, Centre and Huntingdon Counties, Pennsylvania, Water Years 2000–06

This report describes the results of a study by the U.S. Geological Survey in cooperation with ClearWater Conservancy and the Pennsylvania Department of Environmental Protection to develop a hydrologic model to simulate a water budget and identify areas of greater than average recharge for the Spring Creek Basin in central Pennsylvania. The model was developed to help policy makers, natural resource managers, and the public better understand and manage the water resources in the region. The Groundwater and Surface-water FLOW model (GSFLOW), which is an integration of the Precipitation-Runoff Modeling System (PRMS) and the Modular Groundwater Flow Model (MODFLOW-NWT), was used to simulate surface water and groundwater in the Spring Creek Basin for water years 2000–06. Because the groundwater and surface-water divides for the Spring Creek Basin do not coincide, the study area includes the Nittany Creek Basin and headwaters of the Spruce Creek Basin. The hydrologic model was developed by the use of a stepwise process: (1) develop and calibrate a PRMS model and steady-state MODFLOW-NWT model; (2) re-calibrate the steady-state MODFLOW-NWT model using potential recharge estimates simulated from the PRMS model, and (3) integrate the PRMS and MODFLOW-NWT models into GSFLOW. The individually calibrated PRMS and MODFLOW-NWT models were used as a starting point for the calibration of the fully coupled GSFLOW model. The GSFLOW model calibration was done by comparing observations and corresponding simulated values of streamflow from 11 streamgages and groundwater levels from 16 wells. The cumulative water budget and individual water budgets for water years 2000–06 were simulated by using GSFLOW. The largest source and sink terms are represented by precipitation and evapotranspiration, respectively. For the period simulated, a net surplus in the water budget was computed where inflows exceeded outflows by about 1.7 billion cubic feet (0.47 inches per year over the basin area); storage increased by about the same amount to balance the budget. The rate and distribution of recharge throughout the Spring Creek, Nittany Creek, and Spruce Creek Basins is variable as a result of the high degree of hydrogeologic heterogeneity and karst features. The greatest amount of recharge was simulated in the carbonate-bedrock valley, near the toe slopes of Nittany and Tussey Mountains, in the Scotia Barrens, and along the area coinciding with the Gatesburg Formation. Runoff extremes were observed for water years 2001 (dry year) and 2004 (wet year). Simulated average recharge rates (water reaching the saturated zone as defined in GSFLOW) for 2001 and 2004 were 5.4 in/yr and 22.0 in/yr, respectively. Areas where simulations show large variations in annual recharge between wet and dry years are the same areas where simulated recharge was large. Those areas where rates of groundwater recharge are much higher than average, and are capable of accepting substantially greater quantities of recharge during wet years, might be considered critical for maintaining the flow of springs, stream base flow, or the source of water to supply wells. The slopes of the Bald Eagle, Tussey, and Nittany Mountains are relatively insensitive to variations in recharge, primarily because of reduced infiltration rates and steep slopes.

Pennsylvania↗
USGS2022

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

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

Montana, North Dakota, South Dakota↗
USGS2012

Foreword: Contributions of Arctic PRISM to monitoring western hemispheric shorebirds

Long-term monitoring of populations is of paramount importance to understanding responses of organisms to global environmental change and to evaluating whether conservation practices are yielding intended results through time (Wiens 2009). The population status of many shorebird species, the focus of this volume, remain poorly known. Long-distance migrant shorebirds have proven particularly difficult to monitor, in part because of their highly inaccessible regions. As migrant shorebirds travel the length of the hemisphere, the congregate and disperse in ways that vary among species, locations, and years, presenting serious challenges to designing and implementing monitoring programs. Rigorous field and quantitative methods that estimate population size and monitor trends are vitally needed to direct and evaluate effective conservation measures. Many management efforts depend on unbiased population size estimates; for examples, the shorebird conservation plans for both Canada and the United States seek to restore populations to levels calculated for the 1970s based on the best information available from existing surveys. Further, federal wildlife agencies within the United States and Canada have mandates to understand the state of their nations' resources under various conventions for the protection of migratory birds. Accurate estimates of population size are vital statistics for a variety of conservation activities, such as prioritizing species for conservation action and setting management targets. Areas of essential habitat, such as those designated under the Western Hemisphere Shorebird Reserve Network, the Important Bird Areas program of BirdLife Internationals and the National Audubon Society, or Canada's National Wildlife Areas program, are all evaluated on the basis of proportions of species' populations which they contain. The size, and trends in size, of a species' population are considered key information for assessing its vulnerability and subsequent listing under the U.S. Endangered Species Act and the Canadian Species at Risk Act. To meet the need for information on population size and trends, shorebird biologists from Canada and the United States proposed a shared blueprint for shorebird monitoring across the Western Hemisphere in the late 1990s; this effort was undertaken in concert with the development of the Canadian and the U.S. Shorebird Conservation Plans. Soon thereafter, partners in the monitoring effort adopted the name "Program for Regional and International Shorebird Monitoring" (PRISM). Among the primary objectives of PRISM were to estimate the population sizes and trends of breeding North American shorebirds and describe their distributions. PRISM members evaluated ongoing and potential monitoring approached to address 74 taxa (including subspecies) and proposed a combination of arctic and boreal breeding surveys, temperate breeding and non-breeding surveys, and neotropical surveys.

Studies in Avian Biology↗
USGS2012

Contributions of Arctic PRISM to monitoring western hemispheric shorebirds

Long-term monitoring of populations is of paramount importance to understanding responses oforganisms to global environmental change and to evaluating whether conservation practices are yielding intended results through time (Wiens 2009). The population status of many shorebird species, the focus of this volume, remain poorly known. Long-distance migrant shorebirds have proven particularly difficult to monitor, in part because of their highly migratory nature and ranges that extend into highly inaccessible regions. As migrant shorebirds travel the length of the hemisphere, they congregate and disperse in ways that vary among species, locations, and years, presenting serious challenges to designing and implementing monitoring programs. Rigorous field and quantitative methods that estimate population size and monitor trends are vitally needed to direct and evaluate effective conservation measures. Many management efforts depend on unbiased population size estimates; for example, the shorebird conservation plans for both Canada and the United States seek to restore populations to levels calculated for the 1970s based on the best information available from existing surveys. Further, federal wildlife agencies within the United States and Canada have mandates to understand the state of their nations' resources under various conventions for the protection of migratory birds. Accurate estimates of population size are vital statistics for a variety of conservation activities, such as prioritizing species for conservation action and setting management targets. Areas of essential habitat, such as those designated under the Western Hemisphere Shorebird Reserve Network, the Important Bird Areas program of BirdLife International and the National Audubon Society, or Canada's National Wildlife Areas program, are all evaluated on the basis ofproportions of species' populations which they contain. The size, and trends in size, ofa species' population are considered key information for assessing its vulnerability and subsequent listing under the U.S. Endangered Species Act and the Canadian Species at Risk Act. To meet the need for information on population size and trends, shorebird biologists from Canada and the United States proposed a shared blueprint for shorebird monitoring across the Western Hemisphere in the late 1990s; this effort was undertaken in concert with the development of the Canadian and U.S. Shorebird Conservation Plans (Donaldson et al. 2000, Brown et aL 2001). Soon thereafter, partners in the monitoring effort adopted the name "Program for Regional and International Shorebird Monitoring" (PRISM). Among the primary objectives of PRISM were to estimate the population sizes and trends of breeding North American shorebirds and describe their distributions (Bart et al. 2002). PRISM members evaluated ongoing and potential monitoring approaches to address 74 taxa (including subspecies) and proposed a combination of arctic andboreal breeding surveys, temperate breeding and non-breeding surveys, and neotropical surveys.

Book chapter↗
USGS2003

Geographic Information System Tools for Conservation Planning: User's Manual

Public and private land managers desire better ways to incorporate landscape, species, and habitat relations into their conservation planning processes. We present three tools, developed for the Environmental Systems Research Institute?s ArcView 3.x platform, applicable to many types of wildlife conservation management and planning efforts. These tools provide managers and planners with the ability to rapidly assess landscape attributes and link these attributes with species-habitat information. To use the tools, the user provides a detailed land cover spatial database and develops a matrix to identify species-habitat relations for the landscape of interest. The tools are applicable to any taxa or suite of taxa for which the required data are available. The user also has the ability to interactively make polygon-specific changes to the landscape and re-examine species-habitat relations. The development of these tools has given resource managers the means to evaluate the merits of proposed landscape management scenarios and to choose the scenario that best fits the goals of the managed area.

Information and Technology Report↗
USGS1995

North American migratory bird management issues

As human population and industry have grown in North America, land-use practices have greatly altered the landscape. As a result of this changed landscape, several migratory bird populations have declined in recent years. For waterbirds, there have been several milestones: the 1986 North American Waterfowl Management Plan (NAWMP) and the 1989 North American Wetlands Conservation Act. As a result, the United States and Canada have established 12 habitat and 2 species joint ventures. The primary emphasis of waterfowl management in Canada-U.S. has been land purchase and lease, wetland restoration, and coordination of harvest rates. Because of its different biological and cultural context, Mexico has established other conservation priorities. Mexico has had a long-standing concern to conserve its biodiversity and, in addition, conservation of Mexican resources goes hand in hand with human community development. Unlike Canada-U.S., wetland conservation projects in'Mexico include information gathering, environmental education, and management planning for its 32 priority wetlands. For migratory landbirds' scientists attribute declines in several migrant populations to forest fragmentation on the breeding grounds, deforestation on the wintering grounds, pesticide poisoning, or the cumulative effects of habitat changes. In 1990, the Neotropical Migratory Bird Conservation Program, commonly known as Partners in Flight-Aves de las Americas-was initiated. The next step that is being proposed is the formation of a habitat conservation plan for landbirds modeled after the NAWMP. Management of migratory birds requires a strong international approach in order to coordinate actions for the benefit of migratory birds, their habitats, and the uses they provide.

Wildlife Society Annual Conference↗
USGS2026

Restoration is a partial but not complete solution for long-term declines in oyster populations—A case history from the northeastern Gulf of America

Objective We sought to evaluate whether oyster reef restoration is associated with sustained increases in intertidal eastern oyster Crassostrea virginica density in Suwannee Sound, Florida, and to examine how commercial fishing activity and freshwater discharge may modify those patterns. Methods We monitored intertidal oyster reefs for 14 years, including 9 years prior to large-scale restoration (completed in 2018) and 5 years of standardized postrestoration monitoring beginning in 2019 at Lone Cabbage Reef, an offshore intertidal reef complex that was rebuilt to target elevation using dolomite limestone. A Bayesian negative-binomial generalized linear mixed model framework estimated oyster densities while accounting for spatial differences among inshore, nearshore, and offshore reefs; variation in transect length; and temporal variability. We assessed restoration effectiveness via repeated-measures monitoring of fixed restored sites and landscape-scale comparisons of restored versus unrestored reefs. We evaluated covariates of management interest—commercial fishing activity and river discharge—using model comparison and posterior predictions of oyster density at observed covariate values. Results Restoration produced large per-area gains in live-oyster density on offshore reefs. At four fixed restored offshore stations, mean densities rose from near 0 to 91 oysters/m 2 (95% credible interval [CrI] = 43–185) within 6 months and reached 244 oysters/m 2 (95% CrI = 134–433) by year 5 at fixed restoration stations. At the broader landscape scale, restored offshore reefs averaged about 83 oysters/m 2 (95% CrI = 26–157) across sites and postrestoration periods, whereas model-based estimates for restored offshore reefs reached 218 oysters/m 2 (95% CrI = 128–366) in the final sampling period. Conclusions Restoring reef substrate rebuilt the physical capacity for oysters to persist and grow at Lone Cabbage Reef, yielding sustained density gains that degraded sites did not achieve on their own. Harvest status and river discharge showed weak, inconsistent associations once restoration was included, consistent with the interpretation that oyster cultch provides structural capacity, while environmental and fishing conditions modulate around it. Rebuilding and conserving oyster cultch constitute the essential first step to repair and sustain degraded oyster reefs; fishing regulations or favorable environmental conditions alone are unlikely to replace the need for reef structure.

Florida↗
USGS2025

Environmental characteristics of select managed ponds in the Sacramento–San Joaquin Delta—Implications for native fish conservation and research

The use of wetlands to support native fish research and conservation efforts in the Sacramento–San Joaquin Delta (Delta) of California is a growing priority. The purpose of our study was to examine the physiochemical and biological characteristics of select managed ponds in the Delta to determine if they would be suitable habitats for research involving the conservation of delta smelt ( Hypomesus transpacificus ). We studied 10 managed ponds distributed across the central part of the Delta situated on Bacon Island and Bouldin Island in San Joaquin County, and Holland Tract and Webb Tract islands in Contra Costa County. The managed ponds had a diversity of physical habitat configurations and were not directly connected to waterways surrounding the islands and, therefore, not affected by tides. We studied the managed ponds from approximately November 2021 to December 2023 to assess water quality, zooplankton, fish, and pesticide metrics. Water levels in the managed ponds were managed to varying degrees and were mostly independent of climate-driven wet-dry seasonality. Water quality conditions varied among ponds and were independent of geographic location. Overall, mean monthly chlorophyll a concentration ranged from 15 to 57 (mean=30) micrograms per liter (μg/L), dissolved oxygen concentration ranged from 4 to 9 (mean=7) milligrams per liter (mg/L), pH was 8, salinity was 1 practical salinity units (PSU), specific conductance ranged from 1,202 to 1,839 (mean=1,471) microsiemens per centimeter (μS/cm), and turbidity ranged from 13 to 24 (mean=19) Formazin Nephelometric Units (FNU). Water temperature thresholds that contribute to stress (21 degrees Celsius [°C]) and mortality (28 °C) of delta smelt were often exceeded during summer and fall, though vertical stratification contributed to lower bottom temperatures in the deepest managed ponds, which could potentially provide thermal refugia for delta smelt so long as dissolved oxygen concentrations are suitable. Zooplankton populations were broadly similar among managed ponds and included calanoid and cyclopoid copepods that would be suitable prey for delta smelt. Overall average total zooplankton biomass, as measured with a Schindler-Patalas trap, was 0.6 μg/L (min=0, max=63.6) and peaked during spring at more than 4 μg/L. Fish populations highly varied among the managed ponds with potential predators of delta smelt such as largemouth bass ( Micropterus salmoides ) and black crappie ( Pomoxis nigromaculatus ) present in several of the managed ponds; predator distribution among ponds seemed to have been driven primarily by deliberate stocking to facilitate local fisheries. Measured pesticide concentrations were below U.S. Environmental Protection Agency Aquatic Life Benchmarks except for exceedances of three compounds (diuron [herbicide], clothianidin [insecticide], and deltamethrin [pyrethroid insecticide]) in samples collected from ponds on Bouldin Island and Webb Tract. Overall, most managed ponds seemed suitable to support delta smelt, though physical control of potential predators and summer temperature might be needed. The results provide guidance on how to engineer and manage new managed ponds to support research and conservation efforts for delta smelt and other native fishes.

California↗
USGS2019

Integrating behavior and physiology into strategies for amphibian conservation

The amphibian decline crisis has been challenging to address because of the complexity of factors—and their multitude of interactive effects—that drive this global issue. Dissecting such complexity could benefit from strategies that integrate multiple disciplines and address the mechanistic underpinnings of population declines and extirpations. We examine how the disciplines of behavior and physiology could be used to develop conservation strategies for amphibians and identify eight research gaps that provide future directions for the emerging fields of conservation behavior and conservation physiology. We present two case studies on imperiled salamanders that show how studies of behavior and physiology may support amphibian conservation efforts. We found several applications of stress physiology to amphibian conservation, but long-term studies are needed to understand how stress ultimately affects individual fitness and population resilience. Additionally, multiple measures of physiological health are needed to provide a more holistic assessment of an individual’s overall condition. Previous behavioral and physiological studies have been instrumental for understanding how amphibians respond to habitat modification, pathogens and parasites, contaminants, and invasive species. Some behavior-based approaches to mitigating invasive species issues have been successful in short-term studies with individual species. However, widespread application of these tactics has not yet been integrated into conservation and management strategies for ecologically-similar species. A diversity of modeling approaches has enhanced understanding of how climate change may impact amphibian populations, but model predictions need empirical tests to provide conservation managers with workable approaches to multiple perturbations associated with global environmental change. We illustrate that behavior and physiology can have broad utility for amphibian conservation, but evidence is scant that such studies have actually been used to inform strategies for amphibian conservation and management.

Frontiers in Ecology and Evolution↗
USGS2022

Maximizing species distribution model performance when using historical occurrences and variables of varying persistency

Occurrence data used to build species distribution models often include historical records from locations in which the species no longer exists. When these records are paired with contemporary environmental values that no longer represent the conditions the species experienced, the model creates false associations that hurt predictive performance. The extent of mismatching increases with the number of historical occurrences and with inclusion of environmental variables that are prone to change over time. Indeed, the mismatch between occurrence data and contemporaneous environmental variables is a common dilemma when modeling rare or cryptic species, especially those of conservation concern that were once more abundant. Herein, we assess (1) the impact of historical occurrences on model performance across three sets of environmental variables of increasing persistency and (2) the performance of models built using selected-historical occurrences from locations that showed evidence of limited environmental change over time. Concepts are tested on federally listed flatwoods salamanders, reflecting real-world conservation management efforts. We predicted that, compared to other occurrence sets, (1) historical occurrences would perform best with environmental variables that were more persistent, (2) recent occurrences would perform best when the environmental variables were more impersistent, and that (3) our selected-historical occurrences would perform best with a combination of persistent and impersistent variables. Our results showed the expected inversion of model performance of recent and historical occurrences across environmental variables of increasing persistency when evaluated by correct predictions. However, the inversion was not seen in area under the curve performance, in which historical occurrences outperformed recent occurrence models across all variable sets. Selected-historical occurrences did not notably improve performance over all-historical occurrences in any metric or variable set. To maximize utility and performance, modelers could acknowledge potential trade-offs from inclusion of historical occurrences and consider number and age of recent and historical occurrences available, the persistency of environmental variables considered, and how their conservation goals are reflected in model design and evaluation, particularly with respect to sensitivity versus specificity. Our study lends support for inclusion of historical occurrences, with the potential exception of mostly impersistent variables when sensitivity is the highest priority.

Alabama, Florida, Georgia, South Carolina↗
USGS2019

Integrating amphibian movement studies across scales better informs conservation decisions

Numerous papers have highlighted the need to integrate amphibian research and conservation across multiple scales. Despite this, most amphibian movement studies focus on a single level of organization (e.g., local population) and a single life stage (e.g., adults) and many suggest potential conservation actions or imply that the information is useful to conservation, yet these presumptions are rarely clarified or tested. Movement studies to date provide little information to guide conservation decisions directly because they fail to integrate movement across scales with individual or population parameters (i.e., fitness metrics); this is exacerbated by a general failure to set movement studies in a probabilistic context. An integrative approach allows prediction of population or metapopulation responses to environmental changes and different management actions, thus directly informing conservation decisions and ‘moving the needle’ towards an informed application of conservation actions. To support this perspective we: 1) revisit reviews of amphibian movement to illustrate the focus on single scales and to underscore the importance of movement – at all scales – to conservation; 2) make the case that movement, breeding, and other demographic probabilities are intertwined and studies executed at different temporal and spatial scales can aid in understanding species' responses to varying environmental and/or management conditions; 3) identify limitations of existing movement-related research to predict conservation action outcomes and inform decision-making; and 4) highlight under-utilized quantitative approaches that facilitate research that either connects movement to fitness metrics (individual-level studies) or estimates population and metapopulation vital rates in addition to, or associated with, movement probabilities.

Biological Conservation↗