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At least 541 records · Page 30Linked to original sources
USGS2016

Species traits and catchment-scale habitat factors influence the occurrence of freshwater mussel populations and assemblages

Conservation of freshwater unionid mussels presents unique challenges due to their distinctive life cycle, cryptic occurrence and imperilled status. Relevant ecological information is urgently needed to guide their management and conservation. We adopted a modelling approach, which is a novel application to freshwater mussels to enhance inference on rare species, by borrowing data among species in a hierarchical framework to conduct the most comprehensive occurrence analysis for freshwater mussels to date. We incorporated imperfect detection to more accurately examine effects of biotic and abiotic factors at multiple scales on the occurrence of 14 mussel species and the entire assemblage of the Tar River Basin of North Carolina, U.S.A. The single assemblage estimate of detection probability for all species was 0.42 (95% CI, 0.36–0.47) with no species- or site-specific detection effects identified. We empirically observed 15 mussel species in the basin but estimated total species richness at 21 (95% CI, 16–24) when accounting for imperfect detection. Mean occurrence probability among species ranged from 0.04 (95% CI, 0.01–0.16) for Alasmidonta undulata, an undescribed Lampsilis sp. , and Strophitus undulatus to 0.67 (95% CI, 0.42–0.86) for Elliptio icterina . Median occurrence probability among sites was <0.30 for all species with the exception of E. icterina . Site occurrence probability generally related to mussel conservation status, with reduced occurrence for endangered and threatened species. Catchment-scale abiotic variables (stream power, agricultural land use) and species traits (brood time, host specificity, tribe) influenced the occurrence of mussel assemblages more than reach- or microhabitat-scale features. Our findings reflect the complexity of mussel ecology and indicate that habitat restoration alone may not be adequate for mussel conservation. Catchment-scale management can benefit an entire assemblage, but species-specific strategies may be necessary for successful conservation. The hierarchical multispecies modelling approach revealed findings that could not be elucidated by other means, and the approach may be applied more broadly to other river basins and regions. Accurate measures of assemblage dynamics, such as occurrence and species richness, are required to create management plans for effective conservation.

Freshwater Biology↗
USGS2014

Successes and challenges from formation to implementation of eleven broad-extent conservation programs

Integration of conservation partnerships across geographic, biological, and administrative boundaries is increasingly relevant because drivers of change, such as climate shifts, transcend these boundaries. We explored successes and challenges of established conservation programs that span multiple watersheds and consider both social and ecological concerns. We asked representatives from a diverse set of 11 broadextent conservation partnerships in 29 countries 17 questions that pertained to launching and maintaining partnerships for broad-extent conservation, specifying ultimate management objectives, and implementation and learning. Partnerships invested more funds in implementing conservation actions than any other aspect of conservation, and a program&rsquo;s context (geographic extent, United States vs. other countries, developed vs. developing nation) appeared to substantially affect program approach. Despite early successes of these organizations and benefits of broad-extent conservation, specific challenges related to uncertainties in scaling up information and to coordination in the face of diverse partner governance structures, conflicting objectives, and vast uncertainties regarding future system dynamics hindered long-term success, as demonstrated by the focal organizations. Engaging stakeholders, developing conservation measures, and implementing adaptive management were dominant challenges. To inform future research on broad-extent conservation, we considered several challenges when we developed detailed questions, such as what qualities of broad-extent partnerships ensure they complement, integrate, and strengthen, rather than replace, local conservation efforts and which adaptive management processes yield actionable conservation strategies that account explicitly for dynamics and uncertainties regarding multiscale governance, environmental conditions, and knowledge of the system?

Conservation Biology↗
USGS2015

Defining conservation targets on a landscape-scale

Conservation planning, the process of deciding how to protect, conserve, enhance and(or) minimize loss of natural and cultural resources, is a fundamental process to achieve conservation success in a time of rapid environmental change. Conservation targets, the measurable expressions of desired resource conditions, are an important tool in biological planning to achieve effective outcomes. Conservation targets provide a focus for planning, design, conservation action, and collaborative monitoring of environmental trends to guide landscape-scale conservation to improve the quality and quantity of key ecological and cultural resources. It is essential to have an iterative and inclusive method to define conservation targets that is replicable and allows for the evaluation of the effectiveness of conservation targets over time. In this document, we describe a process that can be implemented to achieve landscape-scale conservation, which includes defining conservation targets. We also describe what has been accomplished to date (September 2015) through this process for the Peninsular Florida Landscape Conservation Cooperative (PFLCC).

Florida↗
USGS2022

Sea otters in a California estuary: Detecting temporal and spatial dynamics with volunteer monitoring

Volunteer monitoring can support conservation of imperiled wildlife, by providing higher resolution data in space and time than those available from professional scientists. However, concerns have been raised that data collected by amateurs are inaccurate or inconsistent and thus do not allow for robust detection of spatial or temporal trends. We evaluated the rigor and value of volunteer monitoring data for one iconic wildlife species, the southern sea otter ( Enhydra lutris nereis ), in Elkhorn Slough estuary in central California, USA, and explored whether volunteer monitoring could provide added value to complement limited professional surveys. First, we compiled and analyzed sea otter counts taken on daily ecotourist boat trips along the estuary, and then compared temporal patterns to data collected by professional scientists tasked with monitoring this federally listed species. Second, we analyzed data on sea otter abundance, habitat use, and behavior collected by a team of trained volunteers, the Elkhorn Slough Reserve Otter Monitoring Program. Overall, we demonstrated the ability to detect important ecological patterns relevant to sea otter conservation and wetland habitat management using volunteer-derived datasets. Long-term trends and inter-annual variability were similar between professional agency monitoring data and volunteer datasets. Moreover, the much higher frequency of volunteer observations allowed for seasonal and tidal dynamics to be detected that could not be revealed by less frequent professional monitoring. We found higher sea otter abundance in the estuary in spring–summer, indicating seasonality in use of the estuary. We detected differences in habitat use of the estuary between higher and lower tides, and greater frequency of foraging at low tide and in certain areas. Volunteer observations revealed fine-scale differences in habitat use: eelgrass beds were used much more heavily than adjacent areas only a few meters away. Volunteer data can thus provide critical information about coastal habitat use and behavior that can improve conservation strategies for threatened wildlife species.

California↗
USGS2013

Current and future land use around a nationwide protected area network

Land-use change around protected areas can reduce their effective size and limit their ability to conserve biodiversity because land-use change alters ecological processes and the ability of organisms to move freely among protected areas. The goal of our analysis was to inform conservation planning efforts for a nationwide network of protected lands by predicting future land use change. We evaluated the relative effect of three economic policy scenarios on land use surrounding the U.S. Fish and Wildlife Service's National Wildlife Refuges. We predicted changes for three land-use classes (forest/range, crop/pasture, and urban) by 2051. Our results showed an increase in forest/range lands (by 1.9% to 4.7% depending on the scenario), a decrease in crop/pasture between 15.2% and 23.1%, and a substantial increase in urban land use between 28.5% and 57.0%. The magnitude of land-use change differed strongly among different USFWS administrative regions, with the most change in the Upper Midwestern US (approximately 30%), and the Southeastern and Northeastern US (25%), and the rest of the U.S. between 15 and 20%. Among our scenarios, changes in land use were similar, with the exception of our “restricted-urban-growth” scenario, which resulted in noticeably different rates of change. This demonstrates that it will likely be difficult to influence land-use change patterns with national policies and that understanding regional land-use dynamics is critical for effective management and planning of protected lands throughout the U.S.

PLoS ONE↗
USGS2021

Evaluation of hydrologic simulation models for fields with subsurface drainage to mitigated wetlands in Barnes, Dickey, and Sargent Counties, North Dakota

Proper identification of wetlands, along with a better understanding of the hydrology of mitigated wetlands, is needed to assist with conservation efforts aimed at maintaining the productivity and ecological function (wetland mitigation) of agricultural lands. The U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture Natural Resources Conservation Service, completed a study to evaluate two models for simulating hydrologic conditions in fields with subsurface drainage to mitigated wetlands at several sites in North Dakota. These two models were evaluated as possible tools for water resource managers to use for designing wetland mitigation projects in the area in the future. The Soil-Plant-Atmosphere-Water (SPAW) model simulates the daily hydrologic water budgets of agricultural landscapes by two linked routines, one for farm fields (field hydrology) and one for impoundments such as wetlands and ponds (pond model). The DRAINMOD model was used in conjunction with the SPAW model because although the SPAW model can be used to simulate the hydrology of small drainage basins containing wetlands, the SPAW model does not contain routines to simulate drainage, either subsurface drainage or surface (drainage ditches), that can directly affect the wetland hydrology. The wetlands in the study areas in this report are all downstream from and adjacent to drained agricultural fields. SPAW and DRAINMOD models were developed and calibrated at three study areas (study areas B, D, and S) to evaluate how the models simulated field-scale hydrologic characteristics and the water balance in wetlands from January 1, 2003, through December 31, 2018. The SPAW model developed for study area B included five modeled fields in the field hydrology portion of SPAW that contributed inflow to one wetland simulated in the pond model portion of SPAW. Simulated wetland water depths were most similar to water depths measured at site BWET1, with an absolute mean error of 0.10 foot and a root mean square error of 0.14 foot. Site BWET2 had slightly larger errors, with an absolute mean error of 0.22 foot and a root mean square error of 0.28 foot. Simulated water depths were similar to the pattern of measured water depths at BWET1 and BWET2 from about mid-April 2018 through about mid-September 2018, but overpredicted water depths in the fall from about mid-September 2018 through about mid-October 2018. The SPAW model developed for study area D included six modeled fields in the field hydrology portion of SPAW that contributed inflow to five wetlands connected in series in the pond model portion of SPAW. Simulated water depths compared relatively well to water depths in the five wetlands, with the absolute mean error ranging from 0.17 foot (DWET1) to 0.39 foot (DWET2), and the root mean square error ranging from 0.28 foot (DWET1) to 0.56 foot (DWET5). The SPAW model developed for study area S included one modeled field in the field hydrology portion of SPAW that contributed inflow to one wetland in the pond model portion of SPAW. Among the SPAW models developed for the three study areas, the model for study area S had the best comparison between simulated and measured water depths, with an absolute mean error of 0.06 foot and a root mean square error of 0.10 foot. DRAINMOD models were developed and calibrated at the three study areas and provided inflow from subsurface drainage discharge to the SPAW models for simulating water levels in wetlands in the study areas. The calibrated DRAINMOD model for study area B showed the variability of hydrologic processes in the modeled field throughout the wide range of hydrologic conditions from January 1, 2003, through December 31, 2018. In general, the discharge through the modeled subsurface drainage system was in the spring and early summer (April through June) most years, with little to no discharge later in the year. Although the subsurface drainage system in study area D was the most complex among the three study areas and was simplified into a uniform system within DRAINMOD, simulated water table depths at study area D correlated better to measured water table depths compared to results from the model applications at the other two study areas. Simulated water table depths had an absolute mean error of 0.30 foot and root mean square error of 0.37 foot at site DGW1 and an absolute mean error of 0.29 foot and a root mean square error of 0.34 foot at site DGW2. Although the subsurface drainage system in study area S was the simplest and the modeled field was the smallest among the three study areas, simulated water table depths at study area S did not correlate as well to measured water table depths compared to results from the model applications at the other two study areas. The SPAW and DRAINMOD model applications at the three study areas in southeast North Dakota adequately simulated the hydrologic processes for fields with subsurface drainage that are connected to adjacent wetlands. However, more measured data would be needed to fully evaluate the models throughout the range of possible climatic conditions.

North Dakota↗
USGS2011

Guidelines for collecting and maintaining archives for genetic monitoring

Rapid advances in molecular genetic techniques and the statistical analysis of genetic data have revolutionized the way that populations of animals, plants and microorganisms can be monitored. Genetic monitoring is the practice of using molecular genetic markers to track changes in the abundance, diversity or distribution of populations, species or ecosystems over time, and to follow adaptive and non-adaptive genetic responses to changing external conditions. In recent years, genetic monitoring has become a valuable tool in conservation management of biological diversity and ecological analysis, helping to illuminate and define cryptic and poorly understood species and populations. Many of the detected biodiversity declines, changes in distribution and hybridization events have helped to drive changes in policy and management. Because a time series of samples is necessary to detect trends of change in genetic diversity and species composition, archiving is a critical component of genetic monitoring. Here we discuss the collection, development, maintenance, and use of archives for genetic monitoring. This includes an overview of the genetic markers that facilitate effective monitoring, describes how tissue and DNA can be stored, and provides guidelines for proper practice.

Conservation Genetics Resources↗
USGS2011

Conservation and management of crayfishes: Lessons from Pennsylvania

North America's crayfish fauna is diverse, ecologically important, and highly threatened. Unfortunately, up‐to‐date information is scarce, hindering conservation and management efforts. In Pennsylvania and nearby states, recent efforts allowed us to determine the conservation status of several native crayfishes and develop management strategies for those species. Due to rarity and proximity to urban centers and introduced (exotic) crayfishes, Cambarus (Puncticambarus) sp., an undescribed member of the Cambarus acuminatus complex, is critically imperiled in Pennsylvania and possibly range‐wide. Orconectes limosus is more widespread; however, recent population losses have been substantial, especially in Pennsylvania, and northern Maryland, where its range has declined (retreated eastward) by greater than 200 km. Introduced congeners likely played a major role in those losses. Although extirpated from some areas, Cambarus bartonii bartonii remains widespread and is not an immediate conservation concern. In light of these findings, the role of barriers (e.g., dams), environmental protection, educational programs, and regulations in preventing crayfish invasions and conserving native crayfishes is discussed, and management initiatives centered on those factors are presented. The need for methods to eliminate exotics and monitor natives is highlighted. Although tailored to a specific regional fauna, these ideas have broad applicability and would benefit many North American crayfishes.

Pennsylvania↗
USGS2014

Geographic coincidence of richness, mass, conservation value, and response to climate of U.S. land birds

Distributional patterns across the United States of five avian community breeding-season characteristics&mdash;community biomass, richness, constituent species' vulnerability to extirpation, percentage of constituent species' global abundance present in the community (conservation index, CI), and the community's position along the ecological gradient underlying species composition (principal curve ordination score, PC)&mdash;were described, their covariation was analyzed, and projected effects of climate change on the characteristics and their covariation were modeled. Higher values of biomass, richness, and CI were generally preferred from a conservation perspective. However, higher values of these characteristics often did not coincide geographically; thus regions of the United States would differ in their value for conservation depending on which characteristic was chosen for setting conservation priorities. For instance, correlation patterns between characteristics differed among Landscape Conservation Cooperatives. Among the five characteristics, community richness and the ecological gradient underlying community composition (PC) had the highest correlations with longitude, with richness declining from east to west across the contiguous United States. The ecological gradient underlying composition exhibited a demarcation near the 100th meridian, separating the contiguous United States grossly into two similar-sized avian ecological provinces. The combined score (CS), a measure of species' threat of decline or extirpation, exhibited the strongest latitudinal pattern, declining from south to north. Over &sim;75% of the lower United States, projected changes in June temperature and precipitation to year 2080 were associated with decreased averaged values of richness, biomass, and CI, implying decreased conservation value for birds. The two ecological provinces demarcated near the 100th meridian diverged from each other, with projected changes in June temperatures and precipitation from the year 2000 to 2080 suggesting increased ecological dissimilarity between the eastern and western halves of the lower United States with changing climate. Anticipated climate-related changes in the five characteristics by 2080 were more weakly correlated with latitude or longitude then the responses themselves, indicating less distinct geographic patterns of characteristic change than in the characteristics themselves. Climate changes projected for 2080 included geographic shifts in avian biomass, CS, and PC values, a moderate overall decline in CI, and general decline in species richness per site.

Ecological Applications↗
USGS2017

Novel observations of larval fire survival, feeding behavior, and host plant use in the regal fritillary, Speyeria idalia (Drury) (Nymphalidae)

Speyeria idalia is a prairie specialist that has experienced dramatic population declines throughout its range. Speyeria idalia is nearly extirpated from the eastern portion of its former range; however, populations within Kansas are relatively stable. We made several previously undescribed field observations of late-instar larvae and post-diapause female S. idalia in northeastern Kansas during 2014–2016. We report finding late-instar larvae at locations that were burned within weeks of detection. The observations of larvae shortly following a burn suggests that S . idalia larvae are capable of surviving fire and contradicts our current knowledge of this species. Additionally, we describe a feeding behavior characteristic of late-instar larvae. Larvae observed in the field and lab stripped leaves of host plants leaving only stems. This strip-style feeding behavior provided unique feeding evidence that was valuable to detecting the presence of larvae in the field. Finally, we documented larvae and post-diapause, egg depositing females using Viola sororia. The use of this relatively widespread and common plant by S. idalia populations in the Central Great Plains has only been implicitly documented but may have important conservation implications. These novel observations further our knowledge of the ecology of this imperiled species and provide timely information that may improve research and conservation management efforts directed toward S . idalia populations.

Journal of the Lepidopterists' Society↗
USGS2019

Riverscape correlates for distribution of threatened spotfin chub Erimonax monachus in the Tennessee River Basin, USA

Globally, aquatic biodiversity is imperiled at an increasing rate, especially in diversity hotspots such as the southeastern USA. The spotfin chub Erimonax monachus is a federally threatened minnow with a disjunct distribution resulting from numerous impoundments on the Tennessee River and its tributaries in the heart of the southeastern USA. Recovery actions required to remove federal protection for E. monachus are dependent on the establishment of additional populations within the historical range of the species, but little is known regarding macroscale habitat requirements that could guide conservation planning. We analyzed local- and network-scale watershed attributes to develop an ecological niche model (ENM) for E. monachus useful for directing conservation actions at sampled and unsampled sites across the Tennessee River Basin. We found E. monachus occurred most often in larger streams with large upstream catchment areas and minimal alteration to forested uplands, but all of these sites were in close proximity to high densities of downstream dams due to populations being restricted to large-stream habitat upstream of reservoirs. The ENM showed the highest probability of E. monachus occurrence among catchment locations with known extant populations; however, additional historical and previously unoccupied catchments showed potential for successful (re)introductions, provided that fine-scale habitats are appropriate. Our framework can be used to identify potential survey and (re)introduction sites for E. monachus as well as other rare riverine fishes and represents a method for identifying areas of high priority for conserving aquatic biodiversity.

Alabama, Georgia, Kentucky, Mississippi, North Car↗
USGS2022

Managing multiple species with conflicting needs in the Greater Everglades

Given limited funding, natural resources decision making is riddled with tradeoffs, including which species or landscapes to prioritize for management action. Florida’s Everglades wetland is home to numerous indicator species, some of which are endangered. But with a multitude of species comes differing hydrologic requirements to yield appropriate foraging and breeding conditions for each. The Everglades ecosystem is highly managed, with water being moved across the landscape to meet the habitat and reproductive needs of species of concern. Predictive modeling can help water managers understand potential consequences to targeted water conditions. EverForecast is a novel spatially explicit, hydrologic, and ecological operational forecast developed to inform conservation management decisions. Not only does EverForecast provide probable near-term water conditions, but also predicted species responses to those hydrologic conditions. Using examples from two focal regions of the Everglades, we show the magnitude of impacts to a suite of species and an almost 70% decline in suitable conditions for one species when prioritizing water management to meet the needs of another species. Although EverForecast is a relatively new decision support tool, its hydrologic outputs are already commonly used to make water management recommendations because it provides near-term hydrologic forecasts that scientists and managers need for water operations decision making. Because species management decisions have historically been made to target a single species at a time, it may take longer for full utility of EverForecast’s ability to quantify tradeoffs among species to become integrated into decision making.

Florida↗
USGS2022

Stoneflies in the genus Lednia (Plecoptera: Nemouridae): Sentinels of climate change impacts on mountain stream biodiversity

Rapid recession of glaciers and snowfields is threatening the habitats of cold-water biodiversity worldwide. In many ice-sourced headwaters of western North America, stoneflies in the genus Lednia (Plecoptera: Nemouridae) are a prominent member of the invertebrate community. With a broad distribution in mountain streams and close ties to declining glacier cover, Lednia has emerged as a sentinel of climate change threats to high-elevation aquatic biodiversity. Lednia tumana , which is endemic to Glacier National Park, USA and the surrounding mountains, is the most well-studied species in the genus and in 2019 became federally protected under the U.S. Endangered Species Act (ESA) due to climate-induced loss of meltwater habitats. Three other Lednia species have also been described, and like L. tumana , each is endemic to a mountain region of western North America: Lednia sierra in the Sierra Nevada, Lednia borealis in the Cascade Range, and Lednia tetonica in the Teton Range. In this review, we provide a comprehensive overview of Lednia ecology, genetics, and physiology, with an emphasis on the conservation outlook for the group and species with similar headwater distributions. We highlight substantial progress made in the last decade to better understand the ecology and evolution of Lednia , including the identification of 140 Lednia- containing streams (an increase from 12 streams in 2010), and a more complete understanding of the degree to which warming streams may imperil species in the genus. In light of the ESA listing of L. tumana , we show that similar conservation threats likely face all extant Lednia species. However, substantial gaps in our knowledge remain, primarily centering around their distributions (and the potential for as yet undescribed species), life history, ecophysiology, and trophic ecology. We conclude by describing pressing questions for Lednia that when addressed will expand knowledge of the genus and its conservation as well as broader understanding of climate risks to mountain stream biodiversity worldwide.

California, Montana, Washington, Wyoming↗
USGS2021

Can identifying discrete behavioral groups with individual-based acoustic telemetry advance the understanding of fish distribution patterns?

Identifying patterns of organismal distribution can provide valuable insights for basic and applied marine and coastal ecology because understanding where animals are located is foundational to both research and science-based conservation. Understanding variation in distributional patterns can lead to a better assessment of ecological drivers and an improved ability to predict consequences of natural and altered relationships. Here, our purpose is to explore if quantifying coexisting groups of individual fish predators advances our understanding of field distribution patterns. Toward this end, we quantified locations of 59 acoustically tagged striped bass ( Morone saxatilis) within a 26-stationary unit telemetry receiver array in Plum Island Estuary (PIE), MA, United States. We then used cluster analyses on spatial and temporal-spatial metrics from this dataset to (1) assess if distinct groups of individuals coexisted, (2) quantify group characteristics, and (3) test associations between groups and distribution (e.g., physical site type and region). Based on multiple lines of evidence, we identified four groups of striped bass with different space use patterns that persisted across seasons (summer and fall). Similar-sized striped bass clustered at spatial and temporal scales at which individuals within distinct groups could, and did, physically overlap. In addition, distributional groups were linked to components of physical site type and region suggesting that discrete groups of individuals can interact differently with the environment within the same ecological system. The identification of these distinct groups of individuals creates a baseline from which to explore further ecological implications of grouping behavior for research and conservation in geographically large, temporally dynamic, and spatially heterogeneous marine and coastal environments.

Massachusetts↗
USGS2005

Threats, conservation strategies, and prognosis for suckers (Catostomidae) in North America: insights from regional case studies of a diverse family of non-game fishes

Catostomid fishes are a diverse family of 76+ freshwater species that are distributed across North America in many different habitats. This group of fish is facing a variety of impacts and conservation issues that are somewhat unique relative to more economically valuable and heavily managed fish species. Here, we present a brief series of case studies to highlight the threats such as migration barriers, flow regulation, environmental contamination, habitat degradation, exploitation and impacts from introduced (non-native) species that are facing catostomids in different regions. Collectively, the case studies reveal that individual species usually are not threatened by a single, isolated factor. Instead, species in general face numerous stressors that threaten multiple stages of their life history. Several factors have retarded sucker conservation including widespread inabilities of field workers to distinguish some species, lack of basic natural history and ecological knowledge of life history, and the misconception that suckers are tolerant of degraded conditions and are of little social or ecological value. Without a specific constituent group lobbying for conservation of non-game fishes, all such species, including members of the catostomid family, will continue to face serious risks because of neglect, ignorance, and misunderstanding. We suggest that conservation strategies should incorporate research and education/outreach components. Other conservation strategies that would be effective for protecting suckers include freshwater protected areas for critical habitat, restoration of degraded habitat, and design of catostomid-friendly fish bypass facilities. We believe that the plight of the catostomids is representative of the threats facing many other non-game freshwater fishes with diverse life-history strategies globally.

Biological Conservation↗
USGS2025

Answering key bumble bee conservation questions by studying discovered wild nests: A Bombus affinis case study

The nesting ecology of wild bumble bees is not well resolved, but information learned from discovered nests can be of great conservation value. Data collected at nests on foraging patterns, caste-specific behaviour and health (e.g., pathogens) are invaluable for understanding bumble bee behaviour and ecology, but difficult to decipher solely from foraging observations away from the nest. Post-senescence nest excavation allows the estimation of colony size, caste numbers, documents pest incidence and provides opportunities to examine nest material for stressors (e.g., pesticides) and to use nest material for training purposes (e.g., conservation dogs). Wild nests are often found opportunistically, and there is an absence of standardised guidance on data collection. We provide an action plan to ensure the data collection is comparable across studies. This framework includes key conservation questions and methodological guidelines for both for in situ and post-season nest data collection and is ordered by increasing complexity of data collection methods. To illustrate our framework, we provide an example with recently discovered Bombus affinis (rusty patched bumble bee) nests. Through observations at B. affinis nests, we discovered novel patterns of activity, changing activity levels over time, the timing of male and gyne production, variable timing in nest senescence, and associations of nests with past rodent activity. Although individual nest discoveries may be of limited value in forwarding conservation strategies, the aggregate collections of many similar datasets can be of critical importance for species of conservation concern.

Insect Conservation and Diversity↗
USGS2017

An evaluation and comparison of conservation guidelines for an at-risk migratory songbird

For at-risk wildlife species, it is important to consider conservation within the process of adaptive management. Golden-winged Warblers (Vermivora chrysoptera) are Neotropical migratory songbirds that are experiencing long-term population declines due in part to the loss of early-successional nesting habitat. Recently-developed Golden-winged Warbler habitat management guidelines are being implemented by USDA: Natural Resource Conservation Service (2014) and its partners through the Working Lands For Wildlife (WLFW) program. During 2012–2014, we studied the nesting ecology of Golden-winged Warblers in managed habitats of the eastern US that conformed to WLFW conservation practices. We evaluated five NRCS “management scenarios” with respect to nesting success and attainment of recommended nest site vegetation conditions outlined in the Golden-winged Warbler breeding habitat guidelines. Using estimates of territory density, pairing rate, nest survival, and clutch size, we also estimated fledgling productivity (number of fledglings/ha) for each management scenario. In general, Golden-winged Warbler nest survival declined as each breeding season advanced, but nest survival was similar across management scenarios. Within each management scenario, vegetation variables had little influence on nest survival. Still, percent Rubus cover and density of >2 m tall shrubs were relevant in some management scenarios. All five management scenarios rarely attained recommended levels of nest site vegetation conditions for Golden-winged, yet nest survival was high. Fledgling productivity estimates for each management scenario ranged from 2.1 to 8.6 fledglings/10 hectares. Our results indicate that targeted habitat management for Golden-winged Warblers using a variety of management techniques on private lands has the capability to yield high nest survival and fledgling productivity, and thus have the potential to contribute to the species recovery.

Global Ecology and Conservation↗
USGS2015

Evaluating species richness: biased ecological inference results from spatial heterogeneity in species detection probabilities

Accurate estimates of species richness are necessary to test predictions of ecological theory and evaluate biodiversity for conservation purposes. However, species richness is difficult to measure in the field because some species will almost always be overlooked due to their cryptic nature or the observer's failure to perceive their cues. Common measures of species richness that assume consistent observability across species are inviting because they may require only single counts of species at survey sites. Single-visit estimation methods ignore spatial and temporal variation in species detection probabilities related to survey or site conditions that may confound estimates of species richness. We used simulated and empirical data to evaluate the bias and precision of raw species counts, the limiting forms of jackknife and Chao estimators, and multi-species occupancy models when estimating species richness to evaluate whether the choice of estimator can affect inferences about the relationships between environmental conditions and community size under variable detection processes. Four simulated scenarios with realistic and variable detection processes were considered. Results of simulations indicated that (1) raw species counts were always biased low, (2) single-visit jackknife and Chao estimators were significantly biased regardless of detection process, (3) multispecies occupancy models were more precise and generally less biased than the jackknife and Chao estimators, and (4) spatial heterogeneity resulting from the effects of a site covariate on species detection probabilities had significant impacts on the inferred relationships between species richness and a spatially explicit environmental condition. For a real dataset of bird observations in northwestern Alaska, the four estimation methods produced different estimates of local species richness, which severely affected inferences about the effects of shrubs on local avian richness. Overall, our results indicate that neglecting the effects of site covariates on species detection probabilities may lead to significant bias in estimation of species richness, as well as the inferred relationships between community size and environmental covariates.

Ecological Applications↗