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Abstract Currently 1677 species are listed under the U.S. Endangered Species Act (ESA), yet only a small percentage have been delisted due to recovery. In the fall of 2021, the U.S. Fish and Wildlife Service proposed delisting 23 species due to extinction. Tracking changes in species ‘recovery status over time is critical to understanding species’ statuses, informing adaptive management strategies, and assessing the performance of the ESA to prevent further species loss. In this paper, we describe four key obstacles in tracking species recovery status under the ESA. First, ESA 5‐year reviews lack a standardized format and clear documentation. Second, despite having been listed for decades, many species still suffer major data gaps in their biology and threats, rendering it difficult if not impossible to track progress towards recovery. Third, many species have continued declining after listing, yet given the above (1 & 2), understanding potential causes (proximate and/or ultimate) can be difficult. Fourth, many species currently have no path to clear recovery, which represents a potential failing of the process. We conclude with a discussion of potential policy responses that could be addressed to enhance the efficacy of the ESA.

Abstract The Endangered Species Act (ESA) provides legal protection to imperiled populations and their associated habitats. As a part of this process, listed species must undergo a general status review (also called 5‐Year Review) to assess the progress toward recovery every 5 years. However, almost all 5‐year reviews result in a status of “no change,” prompting scientists to question if the review process is robust enough to detect changes in recovery. The U.S. Fish and Wildlife Service (USFWS) was therefore interested in developing a standardized metric for monitoring more nuanced recovery progress as part of the status review. In collaboration with the USFWS, over 75 biologists from five different organizations developed and tested a set of novel metrics to summarize recovery progress of listed species by considering current and future conditions, threats, and conservation measures. We found that, although the majority of species had reviews with a recommendation of no change, scorers were able to use the metrics to interpret more nuanced changes in the 3Rs (resiliency, redundancy, and representation), threats, and conservation measures than in the status review. Our results suggest that these metrics could illuminate more nuanced areas of recovery and decline in species' conditions, but consistency among scorers and status reports should be a focus of future development. Our approach offers a rigorous set of metrics to systematically track the recovery progress of all ESA species.

Abstract Environmental DNA (eDNA) analysis is an effective and non‐invasive technique for surveying and monitoring rare, threatened, or endangered (RTE) species. Compared to conventional capture‐based sampling, eDNA analysis may offer a more cost‐effective approach for surveying RTE species, yet few studies have compared their cost‐efficiency—a critical consideration for conservation planning. We compared the costs, effort, and relative performance of aquatic eDNA sampling and conventional trapping for detecting the Alligator Snapping Turtle, Macrochelys temminckii Troost, 1835, in southwest Louisiana, United States. Environmental DNA was sampled quarterly over 1 year (2018–2019) at 19 streams, including three streams where M. temminckii presence had been previously confirmed via conventional trapping efforts (2012–2013). Water samples from each stream were analyzed using quantitative polymerase chain reaction (qPCR) to assess M. temminckii eDNA presence/absence. Time and costs (i.e., labor, travel, wages, and supplies) per detection via eDNA analysis and trapping were calculated and compared. Environmental DNA analysis documented the presence of M. temminckii DNA at two of the three streams where individuals had previously been trapped and yielded detections (qPCR amplifications) at 16 additional streams not previously sampled, expanding M. temminckii's documented distribution at our study sites by 84%. Environmental DNA analysis returned a detection rate (per site) 5.55 times higher than conventional trapping and was 18.7% less expensive. Our results provide evidence that strategically deployed eDNA surveys may be an effective and cost‐efficient approach for detecting freshwater RTE species. With eDNA analysis, additional resources can be invested toward expanding survey coverage and increasing sampling frequency, allowing managers to more effectively target subsequent intensive monitoring efforts.

Abstract Arthropods can strongly impact ecosystems through pollination, herbivory, predation, and parasitism. As such, characterizing arthropod biodiversity is vital to understanding ecosystem health, functions, and services. Emerging environmental DNA (eDNA) methods targeting trace arthropod eDNA left behind on flowers have the potential to track arthropod biodiversity and interactions. The goal of this study was to determine the extent to which eDNA metabarcoding can identify plant‐arthropod and arthropod‐arthropod interactions and assess eDNA metabarcoding compared to conventional sampling. We deployed camera traps to document arthropod activity on specific flowers, sampled eDNA from those same flowers, then performed a metabarcoding analysis that targets a partial fragment of the cytochrome c oxidase subunit I gene (COI) to determine all arthropod eDNA present. We found that our eDNA metabarcoding analysis detected small arthropod pollinators, plant pests, and parasites, and shed light on potential predator–prey interactions while detecting 55 species compared to just 21 species from conventional camera trapping. The camera trapping survey, however, detected larger, more conspicuous nectarivores more successfully. We also explored the ecology of residual arthropod eDNA, finding that rainfall had a significant negative effect on the ability to detect residual arthropod eDNA. Preliminary evidence also indicates flower species may impact the amount of arthropod eDNA that can be detected. We found that eDNA metabarcoding can provide clues to potential predator–prey interactions on flowers and highlights the potential insights that can be gained from future eDNA metabarcoding studies. We show that eDNA metabarcoding is a valuable tool for not only detecting pollinator communities but for revealing potential interactions among plants, pollinators, pests, parasites, and predators. Future research should focus on how to improve the detection of large pollinators/nectivores and studying the ecology of residual arthropod eDNA to further explore this method's utility.

Abstract Pollinators are declining globally, and this loss can reduce plant reproduction, erode critical ecosystem services and resilience, and drive economic losses. Monitoring pollinator biodiversity trends is essential for adaptive conservation and management, but conventional surveys are often costly, time‐consuming, and requires considerable taxonomic expertise. Environmental DNA (eDNA) metabarcoding surveys are booming due to their rapidity, nondestructiveness, and cost efficiency. Microfluidic technology allows multiple primer sets from different markers to be used in eDNA metabarcoding for more comprehensive inventories, minimizing associated primer bias. We evaluated microfluidic eDNA metabarcoding for pollinator community monitoring in both controlled greenhouse and natural field settings. Using a variety of sampling, preservation, and extraction methods, we assessed pollinator communities with a number of markers using microfluidic metabarcoding. In greenhouse experiments, microfluidic eDNA metabarcoding detected the target bumblebee in two of four focal flower species as well as greenhouse insects in all focal flower species. In the field, numerous common regional arthropods, including some directly observed, were detected. Pollinator detection was maximized using whole flower heads preserved in ATL buffer and extracted with a modified Qiagen® DNeasy protocol for amplification with COI primers. eDNA surveillance could enhance pollinator assessment by detecting protected and endangered species and being more applicable to remote, inaccessible locations, whilst reducing survey time, effort, and expense. Microfluidic eDNA metabarcoding requires optimization to address remaining efficacy concerns, but this approach shows potential in revealing complex networks underpinning critical ecosystem functions and services, enabling more accurate assessments of ecosystem resilience.

Abstract Many animal species exist in fission–fusion societies, where the size and composition of conspecific groups change spatially and temporally. To help investigate such phenomena, social network analysis (SNA) has emerged as a powerful conceptual and analytical framework for assessing patterns of interconnectedness and quantifying group‐level interactions. We leveraged behavioral observations via radiotelemetry and genotypic data from a long‐term (>10 years) study on the pitviper Crotalus atrox (western diamondback rattlesnake) and used SNA to quantify the first robust demonstration of social network structures for any free‐living snake. Group‐level interactions among adults in this population resulted in structurally modular networks (i.e., distinct clusters of interacting individuals) for fidelis use of communal winter dens (denning network), mating behaviors (pairing network), and offspring production (parentage network). Although the structure of each network was similar, the size and composition of groups varied among them. Specifically, adults associated with moderately sized social groups at winter dens but often engaged in reproductive behaviors—both at and away from dens—with different and fewer partners. Additionally, modules formed by individuals in the pairing network were frequently different from those in the parentage network, likely due to multiple mating, long‐term sperm storage by females, and resultant multiple paternity. Further evidence for fission–fusion dynamics exhibited by this population—interactions were rare when snakes were dispersing to and traversing their spring–summer home ranges (to which individuals show high fidelity), despite ample opportunities to associate with numerous conspecifics that had highly overlapping ranges. Taken together, we show that long‐term datasets incorporating SNA with spatial and genetic information provide robust and unique insights to understanding the social structure of cryptic taxa that are understudied.

Abstract Successful conservation of rare, threatened, or endangered (RTE) species is dependent upon rapid and accurate assessment of their distribution and abundance. However, assessments are challenging as RTE species typically exist as numerically small populations in often fragmented habitats and can possess complex natural histories. Environmental DNA (eDNA) analysis may provide a rapid, cost‐effective means of assessing RTE species presence/absence in viable habitat patches. We evaluated the efficacy of eDNA surveillance for the Louisiana Pinesnake (Pituophis ruthveni), an elusive, semi‐fossorial, nonvenomous colubroid snake endemic to Louisiana and Texas, USA, that has dramatically declined in both distribution and abundance. We developed two quantitative polymerase chain reaction (qPCR) assays that target the mitochondrial cytochrome c oxidase subunit I (COI) and mitochondrially encoded ATP synthase membrane subunit 6 (ATP6) genes. We validated each assay in silico, in vitro, and in situ, and investigated the influence of eDNA extraction method and genetic marker on assay performance. Both assays were highly sensitive and successfully detected the Louisiana Pinesnake under artificial and field conditions, including bedding samples collected from captive snake enclosures (100%), soil samples from Louisiana Pinesnake release sites (100%), and soil samples from sites where Louisiana Pinesnakes were documented via radio telemetry (45%). Although differences between genetic markers were negligible, assay performance was strongly influenced by eDNA extraction method. Informed by our results, we discuss methodological and environmental factors influencing Louisiana Pinesnake eDNA detection and quantification, broader implications for management and conservation of the Louisiana Pinesnake and other terrestrial reptiles and provide recommendations for future research. We suggest that eDNA surveys can more effectively assess Louisiana Pinesnake occupancy than conventional sampling, highlighting the need for comprehensive eDNA monitoring initiatives to better identify suitable habitat that will promote persistence of this imperiled species going forward.

Cryptic species present particular challenges to biodiversity conservation, as true species diversity and distributional boundaries remain obscured. However, modern molecular tools have afforded unparalleled opportunities to elucidate cryptic species, define their distributions, and, ultimately, develop conservation interventions to extend their evolutionary trajectories into the future. The Green Salamander (Aneides aeneus) complex provides an evolutionary focal point and the Appalachian Highlands an ecological context for the exploration of cryptic speciation in an imperiled taxon. A recent study uncovered significant levels of genetic and genomic variation geographically structured across the Appalachian Highlands, including up to four lineages, one of which (A. caryaensis) was described therein. Here we extend the genetic and genomic examination of the Castaneides species complex by intensive sampling of additional populations along Cumberland Plateau and Appalachian Valley and Ridge of Alabama and Tennessee, employing both mtDNA and RADseq species delimitation approaches to delineate cryptic diversity and boundaries in this region. Analyses of two mitochondrial loci (nd4 and cytb) identified two reciprocally monophyletic lineages, which are also supported by population clustering and phylogenetic analyses of SNPs, that identified two population clusters with no evidence of gene flow. Our genetic and genomic results support the recognition of two additional cryptic lineages in the Castaneides species complex. Ultimately, this information is critical in developing successful adaptive management strategies for this important and endemic component of Appalachian Highland biodiversity.

Abstract The need for efficient, accurate biodiversity monitoring is growing, especially for globally imperiled taxa, such as amphibians. Environmental DNA (eDNA) analysis holds enormous potential for enhancing monitoring programs, but as this tool is increasingly adopted, it is imperative for users to understand its potential benefits and shortcomings. We conducted a comparative study to evaluate the efficacy of two eDNA methodologies (quantitative (q)PCR and metabarcoding) and conventional field sampling approaches (seining, dipnetting, and visual encounter surveys) in a system of 20 ponds containing six different amphibian species. Using an occupancy modeling framework, we estimated differences in detection sensitivity across methods, with a focus on how eDNA survey design could be further optimized. Overall, both metabarcoding and qPCR were competitive with or improved upon conventional methods. Specifically, qPCR (species‐specific approach) was the most effective technique for detecting two rare species, the California tiger salamander (Ambystoma californiense) and California red‐legged frog (Rana draytonii), with a detection probability of >0.80 per survey. Metabarcoding (community approach) estimated amphibian diversity with comparable rates to field techniques on average, and detected an additional 41 vertebrate taxa. However, for two abundant species (western toads, Anaxyrus boreas, and Pacific chorus frogs, Pseudacris regilla), field techniques outperformed metabarcoding, especially as individuals metamorphosed. Our results indicate that eDNA approaches would be most effective when paired with visual encounter surveys to detect terrestrial life stages, and that more optimization, specifically primer choice and validation, is needed. By comparing methods across a diverse set of ponds and species, we provide guidance for future studies integrating eDNA approaches into amphibian monitoring.

The importance of vertebrate animals as seed dispersers (zoochory) has received increasing attention from researchers over the past 20 years, yet one category in particular, diploendozoochory, remains understudied. As the term implies, this is a two-phase seed dispersal system whereby a secondary seed predator (carnivorous vertebrate) consumes a primary seed predator or granivore (rodent and bird) with undamaged seeds in their digestive tract (mouth, cheek pouch, crop, stomach, or other organ), which are subsequently eliminated with feces. Surprisingly, although snakes are among the most abundant predators of granivorous vertebrates, they are the least studied group insofar as our knowledge of seed rescue and secondary dispersal in a diploendozoochorous system. Here, using live snake subjects of the Sonoran Desert (one viperid and two colubrid species) and seeds of the Foothill Palo Verde (Parkinsonia microphylla), a dominant tree of the same region, we experimentally tested germination frequency and rate, and seedling viability. Specifically, to mimic rodents with seed-laden cheek pouches, we tested whether wild-collected P. microphylla seeds placed in the abdomen of thawed laboratory mice and ingested by the snakes would retain their germination viability. Second, we examined whether seeds exposed to gut transit germinated at a greater frequency and rate than the controls. While we found strong statistical support for our first hypothesis, both aspects of the second one were not significant. Accordingly, we provide an explanation for these results based on specific life-history traits (dormant and non-dormant seeds) of P. microphylla. Our study provides support for the role of snakes as important agents of seed rescue and dispersal in nature, their potential as ecosystem engineers, and crucial evidence for the investment of field-based studies on diploendozoochorous systems in deserts and other ecosystems.

Abstract Due to decades of fire suppression, much of the Upper Midwest savanna habitat has converted to oak woodland. In efforts to restore oak savanna habitat, fire has been re‐introduced in many of these woodlands. A primary purpose of these burns is to kill the fire‐sensitive mesophytic tree species, which had established themselves during the decades of fire suppression, reduce the number of understory trees, and preserve the larger more widely spaced oaks. It is clear from ongoing efforts that restoring oak savannas will require frequent fires over decades, but frequent fires over the long term can also threaten the desirable oaks. Long‐term demographic studies at savanna restoration sites experiencing frequent fires are necessary to determine the extent to the frequent burns are supporting and/or confounding restoration goals. Results presented here are from a twenty‐five‐year demographic study of an Upper Midwest bur oak (Quercus macrocarpa) savanna/woodland experiencing frequent fire, during which both the survival and growth of more than 9000 trees were documented. Survival was assessed annually and growth every five years. In the face of frequent fires, stem survival was found to be strongly associated with tree species, stem size, and stem growth. In turn, stem growth was found to be related to tree species and stem size. Decades of frequent burning in this oak woodland have substantially reduced the abundance of unwanted trees, specifically mesophytic species and Quercus ellipsoidalis, the latter which outcompetes Q. macrocarpa in the absence of fire. While Q. macrocarpa mid‐sized (10–25 cm dbh) and large (≥25 cm dbh) trees are quite resistant to fire and now dominate the savanna landscape, they are not immune from fire‐induced mortality. It is recommended that the number and density of these trees should be re‐evaluated every few years to ensure that desirable numbers remain. If necessary, fires should be suspended for a period of time. This will give smaller Q. macrocarpa trees time to grow larger and become more fire‐resistant, thereby ensuring successive generations of Q. macrocarpa.

Abstract Background Imperfect detection of hard‐to‐sample organisms has motivated the development of novel monitoring techniques. Environmental DNA (eDNA) can provide a sensitive, relatively low‐cost sampling method in aquatic systems, but biotic and abiotic factors can affect its reliability. Aims We used a reintroduced population of radio‐tracked alligator snapping turtles (Macrochelys temminckii) to test the efficacy and ecology of eDNA in a lotic system. Materials & Methods We collected samples at turtle locations as well as random up‐ and downstream sites. Using a novel eDNA assay, we modeled occupancy and detection of eDNA using turtle biomass and remotely sensed UV exposure and also tested the relationship between these parameters and eDNA concentration. Results We found eDNA occupancy was best explained by upstream biomass and detection probability decreased with greater upstream UV exposure. The concentration of eDNA in a sample was not significantly affected by biomass measures, but decreased with higher upstream UV exposure, and the effect was significant. Discussion Our results show that UV exposure can affect aquatic eDNA sampling in situ with free‐ranging animals. The use of radiotelemetry allowed for higher control when modeling eDNA persistence and transport in a natural setting relative to laboratory, enclosure, or mesocosm studies. Conclusion We propose using wildlife tracking techniques to provide added realism to studies of eDNA dynamics.

Thirty-one species of Nearctic Perlesta Banks, 1906 (Plecoptera: Perlidae) are recognized. A new species is described from western Arkansas and eastern Oklahoma, USA, Perlesta sublobata South & DeWalt, sp. nov., from the adult male, adult female, and egg. Perlesta sublobata males are differentiated from other congeners by a combination of a prominent ventral caecum and a distinct dorsal extension of the lateral sclerites of the aedeagus. A preliminary molecular phylogenetic hypothesis is proposed for Perlesta based on 17 congeners and three outgroup taxa using partial mitochondrial cytochrome c oxidase subunit I sequence data. Illustrations, stereomicroscope images, and scanning electron micrographs support the description and comparison to other Perlesta.

Ecological restoration can promote biodiversity conservation in anthropogenically fragmented habitats, but effectiveness of these management efforts need to be statistically validated to determine ’success.’ One such approach is to gauge the extent of recolonization as a measure of landscape permeability and, in turn, population connectivity. In this context, we estimated dispersal and population connectivity in prairie vole (Microtus ochrogaster; N = 231) and meadow vole (M. pennsylvanicus; N = 83) within five tall-grass prairie restoration sites embedded within the agricultural matrix of midwestern North America. We predicted that vole dispersal would be constrained by the extent of agricultural land surrounding restored habitat patches, spatially isolating vole populations and resulting in significant genetic structure. We first employed genetic assignment tests based on 15 microsatellite DNA loci to validate field-derived species-designations, then tested reclassified samples with multivariate and Bayesian clustering to assay for spatial and temporal genetic structure. Population connectivity was further evaluated by calculating pairwise FST, then potential demographic effects explored by computing migration rates, effective population size (Ne), and average relatedness (r). Genetic species assignments reclassified 25% of initial field identifications (N = 11 M. ochrogaster; N = 67 M. pennsylvanicus). In M. ochrogaster population connectivity was high across the study area, reflected in little to no spatial or temporal genetic structure. In M. pennsylvanicus genetic structure was detected, but relatedness estimates identified it as kin-clustering instead, underscoring social behavior among populations rather than spatial isolation as the cause. Estimates of Ne and r were stable across years, reflecting high dispersal and demographic resilience. Combined, these metrics suggest the agricultural matrix is highly permeable for voles and does not impede dispersal. High connectivity observed confirms that the restored landscape is productive and permeable for specific management targets such as voles and also demonstrates population genetic assays as a tool to statistically evaluate effectiveness of conservation initiatives.

El objetivo de este trabajo es examinar el efecto mediador de la autoficacia, la esperanza y la vitalidad en la relación de la perspectiva futura de tiempo con la satisfacción laboral y el compromiso organizacional. Se aplicó un cuestionario autoinformado a 299 estudiantes de máster con experiencia laboral. Las hipótesis se probaron mediante un análisis de mediación utilizando regresión lineal. Los resultados indican que los tres factores considerados median la relación entre la perspectiva futura de tiempo y la satisfacción laboral. También se encontró que mientras que la autoeficacia y la esperanza median la relación entre la perspectiva futura de tiempo y el compromiso organizacional, la vitalidad no lo hace. Este estudio sugiere que la asociación entre la perspectiva futura de tiempo y las actitudes analizadas no es directa, sino que se transmite, en mayor o menor medida, a través de factores que varían en poder de mediación.