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240 record(s) found.

Papers & Reports Trade-offs in initial and long-term handling efficiency of PIT-tag and photographic identification methods
Authors: Lindsey Roberts; Bennett Hardy; Erin Muths; Abigail Feuka; L L Bailey
Date: 2021-07 | Outlet: Ecological Indicators
Individual identification is required for long-term investigations that examine population-level changes in survival or abundance, and mechanisms associated with these changes in wild populations. Such identification generally requires the application of a unique mark, or the documentation of characteristics distinctive to each individual animal. To minimize impacts to often declining populations, scientific and ethical concerns encourage marking strategies that minimize handling time (i.e., stress) for captured individuals. We examined the relative efficacy of passive integrated transponder (PIT)-tagging and photo-identification to identify individual Boreal toads (Anaxyrus boreas boreas) in field and indoor settings. We evaluated whether initial handling time was influenced by identification method (PIT-tag or photo-identification) or environment (field or indoor) and assessed the applicability of each method in long-term monitoring programs. Initial handling time was higher for PIT-tagging than photo-identification and higher in the field than in an indoor environment; however, handling time for previously PIT-tagged individuals was greatly reduced such that photo-identification led to > 5.5 times more handling time than PIT-tagging over the course of a toad's lifetime. Investigators must determine the trade-off between initial and subsequent handling times to minimize the expected cumulative handling time for an individual over the course of a study. Cumulative handling time is a function of the study design and the species’ survival and detection probabilities. We developed a Shiny Application to allow investigators to determine the identification method that minimizes handling time for their own study system.
Papers & Reports Amphibian population responses to mitigation: relative importance of wetland age and design
Authors: Emily B Oja; L K Swartz; Erin Muths; Blake R Hossack
Date: 2021 | Outlet: Ecological Indicators
Wetland creation is a common practice to mitigate for the loss of natural wetlands. However, there is still uncertainty about how effectively created wetlands replace habitat provided by natural wetlands. This uncertainty is due in part because post-construction monitoring of biological communities, and vertebrates especially, is rare and typically short-term (< 5 years). We estimated occupancy of 4 amphibian species in 8 created mitigation wetlands, 7 impacted wetlands, and 7 reference wetlands in the Greater Yellowstone Ecosystem in Wyoming, USA. Mitigation wetlands were created to replace wetland habitat that was lost during road construction and ranged in age from 1 to 10 years when sampled. Impacted wetlands were natural wetlands partially filled by road construction and were adjacent to a highway. We sampled for amphibian larvae during 6 summers from 2013 to 2020 and used multi-species occupancy models that estimated detection and occupancy of each of 4 amphibian species to determine how amphibian responses changed over time, especially in mitigation wetlands. Occupancy did not differ between impacted and reference wetlands for any of the 4 amphibian species. Western Toads (Anaxyrus boreas) were most common (although briefly) in created wetlands, and occupancy of Columbia Spotted Frogs (Rana luteiventris), Western Tiger Salamanders (Ambystoma mavortium), and Boreal Chorus Frogs (Pseudacris maculata) was lower in created wetlands than in impacted or reference wetlands. Wetland area was positively associated with occupancy for all 4 species and wetland vegetation cover was positively associated with Boreal Chorus Frog and Columbia Spotted Frog occupancy; these results emphasize the importance of design characteristics when planning mitigation wetlands. The link between wetland age and occupancy was complex and included threshold and quadratic relationships for three of the four species, but only Boreal Chorus Frog occupancy was still increasing slowly at the end of our study. Our results indicate created wetlands did not attain the suitability of impacted and natural wetlands for local amphibians, even several years after construction. The complicated relationships between wetland age and species-specific occupancy illustrate the importance of long-term monitoring in describing population responses to the construction of wetlands as mitigation for wetland loss.
Papers & Reports Evaluating Corticosterone as a Biomarker for Amphibians Exposed to Increased Salinity and Ambient Corticosterone
Authors: B J Tornabene; Blake R Hossack; E J Crespi; C W Breuner
Date: 2021-07 | Outlet: Conservation Physiolology 9(1): coab049
Salinization is harmful to amphibians and waterborne corticosterone could be a useful biomarker. Salinity was only associated with waterborne corticosterone for one of three amphibian species. Ambient corticosterone likely confounded associations and possibly influenced amphibian physiology. We provide suggestions to improve reliability of waterborne corticosterone as a biomarker of salt stress.
Papers & Reports Staggered-entry analysis of breeding and occupancy dynamics of Arizona Toads from historically occupied habitats of New Mexico, USA
Authors: M J Forzley; M J Ryan; I M Latella; J T Giermakowski; Erin Muths; Brent H Sigafus; Blake R Hossack
Outlet: Copeia
For species with variable phenology, it is often challenging to produce reliable estimates of population dynamics or changes in occupancy. The Arizona Toad (Anaxyrus microscaphus) is a southwestern USA endemic that has been petitioned for legal protection, but status assessments are limited by a lack of information on population trends. Also, timing and consistency of Arizona Toad breeding varies greatly, making it difficult to predict optimal survey times or effort required for detection. To help fill these information gaps, we conducted breeding season call surveys during 2013–2016 and 2019 at 86 historically occupied sites and 59 control sites across the species’ range in New Mexico. We estimated variation in mean dates of arrival and departure from breeding sites, changes in occupancy, and site-level extinction since 1959 with recently developed multi-season staggered-entry models, which relax the within-season closure assumption common to most occupancy models. Optimal timing of surveys in our study areas was approximately March 5 - March 30. Averaged across years, estimated probability of occupancy was 0.58 (SE = 0.09) for historical sites and 0.19 (SE = 0.08) for control sites. Occupancy increased from 2013 through 2019. Notably, even though observer error was trivial, annual detection probabilities varied from 0.23 to 0.75 and declined during the study; this means naïve occupancy values would have been misleading, indicating apparent declines in toad occupancy. Occupancy was lowest during the first year of the study, possibly due to changes in stream flows and conditions in many waterbodies following extended drought and recent wildfires. Although within-season closure was violated by variable calling phenology, simple multi-season models provided nearly identical estimates as staggered-entry models. Surprisingly, extinction probability was unrelated to the number of years since the first or last record at historically occupied sites. Collectively, our results suggest a lack of large, recent declines in occupancy by Arizona Toads in New Mexico, but we still lack population information from most of the species’ range.
Papers & Reports Demography of the Oregon spotted frog along a hydrologically modified river
Authors: J C Rowe; Adam Duarte; C A Pearl; B McCreary; P K Haggerty; J W Jones; M J Adams
Date: 2021-06-21 | Outlet: Ecosphere
Altered flow regimes can contribute to dissociation between life history strategies and environmental conditions, leading to reduced persistence reported for many wildlife populations inhabiting regulated rivers. The Oregon spotted frog (Rana pretiosa) is a threatened species occurring in floodplains, ponds, and wetlands in the Pacific Northwest with a core range in Oregon, USA. All life stages of R. pretiosa are reliant on aquatic habitats, and inundation patterns across the phenological timeline can have implications for population success. We conducted capture-mark-recapture (CMR) sampling of adult and subadult R. pretiosa at three sites along the Deschutes River downstream from two dams that regulate flows. We related the seasonal extent of inundated habitat at each site to monthly survival probabilities using a robust design CMR model. We also developed matrix projection models to simulate population dynamics into the future under current river flows. Monthly survival was strongly associated with the extent and variability of inundated habitat, suggesting some within-season fluctuations at higher water levels could be beneficial. Seasonal survival was lowest in the winter for all three sites, owing to limited water availability and the greater number of months within this season relative to other seasons. Population growth for the two river-connected sites was most strongly linked to adult survival, whereas population growth at the river-disconnected site was most strongly tied to survival in juvenile stages. This research identifies population effects of seasonally limited water and highlights conservation potential of enhancing survival of particularly influential life stages.
Papers & Reports Enigmatic Near-Extinction in a Boreal Toad Metapopulation in Northwestern Montana
Authors: Rebecca M McCaffery; R E Russell; Blake R Hossack
Outlet: Journal of Wildlife Management
North America’s protected lands harbor significant biodiversity and provide habitats where species threatened by a variety of stressors in other environments can thrive. Yet disease, climate change, and other threats are not limited by land management boundaries and can interact with conditions within protected landscapes to affect sensitive populations. We examined the population dynamics of a boreal toad (Anaxyrus boreas) metapopulation at a wildlife refuge in northwestern Montana over a 16-year period (2003-2018). We used robust design capture-recapture models to estimate male population size, recruitment, and apparent survival over time and in relation to the amphibian chytrid fungus, Batrachochytrium dendrobatidis. We estimated female population size in years with sufficient captures. Finally, we examined trends in male and female toad body size and condition. We found no evidence of an effect of disease or time on male toad survival but detected a strong negative trend in recruitment of new males to the population. Estimates of male and female abundance decreased dramatically over time. Body size of males and females was inversely related to estimated population size, consistent with reduced recruitment to replace adults, but body condition of adult males was only weakly associated with abundance. Together, these results describe the demography of a near-extinction event, and point to dramatic decreases in the recruitment of new individuals to the breeding population as the cause of this decline. We surmise that processes related to the restoration of historical hydrology within the refuge adversely affected amphibian breeding habitat, and that these changes interacted with disease, life history, and other factors to restrict the recruitment of new individuals to the breeding population over time. Our results point to challenges in understanding and predicting drivers of population change and highlight that current metrics for assessing population status can have limited predictive ability.
Papers & Reports Density dependence and adult survival drive dynamics in two high elevation amphibian populations
Authors: A M Kissel; S Tenan; Erin Muths
Date: 2020-12-12 | Outlet: Diversity 2020, 12, 478; doi:10.3390/d12120478
Amphibian conservation has progressed from the identification of declines to mitigation, but efforts are hampered by the lack of nuanced information about the effects of environmental characteristics and stressors on mechanistic processes of population regulation. Challenges include a paucity of long-term data and scant information about the relative roles of extrinsic (e.g., weather) and intrinsic (e.g., density dependence) factors. We used a Bayesian formulation of an open population capture-recapture model and >30 years of data to examine intrinsic and extrinsic factors regulating two adult boreal chorus frogs (Pseudacris maculata) populations. We modelled population growth rate and apparent survival directly, assessed their temporal variability, and derived estimates of recruitment. Populations were relatively stable (geometric mean population growth rate >1), and regulated by negative density dependence (i.e., higher population sizes reduced population growth rate). In the smaller population, density dependence also acted on adult survival. In the larger population, higher population growth was associated with warmer autumns. Survival estimates ranged from 0.30-0.87, per-capita recruitment was <1 in most years, and mean seniority probability was >0.50, suggesting adult survival is more important to population growth than recruitment. Our analysis indicates density dependence is a primary driver of population dynamics for P. maculata adults.
Papers & Reports Estimating the survival of unobservable life stages for a declining frog with a complex life-history.
Authors: Jonathan P Rose; Sarah J Kupferberg; Clara A Wheeler; Patrick M Kleeman; Brian J Halstead
Date: 2021-02-15 | Outlet: Ecosphere 12(2):e03381
Demographic models enhance understanding of drivers of population growth and inform conservation efforts to prevent population declines and extinction. For species with complex life histories, however, parameterizing demographic models is challenging because some life stages can be dif?cult to study directly. Integrated population models (IPMs) empower researchers to estimate vital rates for organisms that have cryptic or widely dispersing early life stages by integrating multiple demographic data sources. For a stream-inhabiting frog(Rana boylii) that is declining through much of its range in Oregon and California, USA, we collected egg-mass counts and capture–mark–recapture data on adults from two populations in California to ?t IPMs that estimate adult abundance and the survival rate of both marked and unobserved life stages. Estimates of adult abundance based on long-term monitoring of egg-mass counts showed that study populations ?uctuated greatly inter-annually but were stable at longer timescales (i.e., decades). Adult female survival during 5–6 yr of capture–mark–recapture study periods was nearly equal in each population. Survival rate of R. boylii eggs to the subadult stage is low on average (0.002) but highly variable among years depending on post-oviposition stream ?ow. Population viability analysis showed that survival of adult and subadult life stages has the greatest proportional effect on population growth; the survival of egg and tadpole life stages, however, is more malleable by management interventions. For example, simulations showed head-starting of tadpoles, salvaging stranded egg masses, and limiting aseasonal pulsed ?ows could dramatically reduce the threat of extirpation. This study demonstrates the value of integrating multiple demographic data sources to construct models of population dynamics in species with complex life histories.
Papers & Reports Conservation genomics of the threatened western spadefoot, Spea hammondii, in urbanized southern California
Authors: K M Neal; R N Fisher; M J Mitrovich; H B Shaffer
Date: 2020-11-27 | Outlet: Journal of Heredity 2020:613-627
Populations of the western spadefoot (Spea hammondii) in southern California occur in one of the most urbanized and fragmented landscapes on the planet and have lost up to 80% of their native habitat. Orange County is one of the last strongholds for this pond-breeding amphibian in the region, and ongoing restoration efforts targeting S. hammondii have involved habitat protection and the construction of artificial breeding ponds. These efforts have successfully increased breeding activity, but genetic characterization of the populations, including estimates of effective population size and admixture between the gene pools of constructed artificial and natural ponds, has never been undertaken. Using thousands of genome-wide single-nucleotide polymorphisms, we characterized the population structure, genetic diversity, and genetic connectivity of spadefoots in Orange County to guide ongoing and future management efforts. We identified at least 2, and possibly 3 major genetic clusters, with additional substructure within clusters indicating that individual ponds are often genetically distinct. Estimates of landscape resistance suggest that ponds on either side of the Los Angeles Basin were likely interconnected historically, but intense urban development has rendered them essentially isolated, and the resulting risk of interruption to natural metapopulation dynamics appears to be high. Resistance surfaces show that the existing artificial ponds were well-placed and connected to natural populations by low-resistance corridors. Toad samples from all ponds (natural and artificial) returned extremely low estimates of effective population size, possibly due to a bottleneck caused by a recent multi-year drought. Management efforts should focus on maintaining gene flow among natural and artificial ponds by both assisted migration and construction of new ponds to bolster the existing pond network in the region.
Papers & Reports The influence of species life history and distribution characteristics on species responses to habitat fragmentation in an urban landscape
Authors: S Amburgey; David AW Miller; C J Rochester; K S Delaney; S PD Riley; C S Brehme; S A Hathaway; R N Fisher
Date: 2021-01-20 | Outlet: Journal of Animal Ecology
1. Fragmentation within urbanized environments often leads to a loss of native species diversity; however, variation exists in responses among-species and among-populations within species.
2. We aimed to identify patterns in species biogeography in an urbanized landscape to understand anthropogenic effects on vertebrate communities and identify species that are more sensitive or resilient to landscape change.
3. We investigated patterns in species richness and species responses to fragmentation in southern Californian small vertebrate communities using multispecies occupancy models and determined factors associated with overall commonness and sensitivity to patch size for 45 small vertebrate species both among and within remaining non-developed patches.
4. In general, smaller patches had fewer species, with amphibian species richness being particularly sensitive to patch size effects. Mammals were generally more common, occurring both in a greater proportion of patches and a higher proportion of the sites within occupied patches. Alternatively, amphibians were generally restricted to larger patches but were more ubiquitous within smaller patches when occupied. Species range size was positively correlated with how common a species was across and within patches, even when controlling for only patches that fell within a species’ range. We found sensitivity to patch size was greater for more fecund species and depended on where the patch occurred within a species’ range. While all taxa were more likely to occur in patches in the warmer portions of their ranges, amphibians and mammals were more sensitive to fragmentation in these warmer areas as compared to the rest of their ranges. Similarly, amphibians occurred at a smaller proportion of sites within patches in drier portions of their ranges. Mammals occurred at a higher proportion of sites that were also in drier portions of their range while reptiles did not differ in their sensitivity to patch size by range position.
5. We demonstrate that taxonomy, life history, range size, and range position can predict commonness and sensitivity of species across this highly fragmented yet biodiverse landscape. The impacts of fragmentation on species communities within an urban landscape depend on scale, with differences emerging among and within species and populations.
Papers & Reports Widespread Ranavirus and Perkinsea infections in Cuban Treefrogs (Osteopilus septentrionalis) invading New Orleans, USA
Authors: N Galt; M S Atkinson; B M Glorioso; J Hardin Waddle; M Litton; Anna E Savage
Date: 2021-04-30 | Outlet: Herpetological Conservation and Biology
Papers & Reports A latent process model approach for improving the utility of indicator species
Authors: Jill Fleming; C Sutherland; S Sterrett; Evan HC Grant
Outlet: Oikos
The state of an ecosystem is governed by dynamic biotic and abiotic processes, which can only be partially observed. Costs associated with measuring each component limit the feasibility of comprehensive assessments of target ecosystems. Instead, indicator species are recommended as a surrogate index. While this is an attractive concept, indicator species have rarely proven to be an effective tool for monitoring ecosystems and informing management decisions. One deficiency in the existing theoretical development of indicator species may be overcome with the incorporation of latent (i.e., unobservable) states. Advancements in quantitative ecological models allow for latent-state models to be tested empirically, facilitating the robust evaluation and practical use of indicator species for ecosystem science and management. Here, we extend the existing conceptual models of indicator species to include a direct relationship between an indicator species, ecosystem change drivers, and latent processes and variables. Our approach includes explicit consideration of important estimation uncertainty and narrows the range of values a latent variable may take by relating it to measurable attribute(s) of an indicator species. We demonstrate the utility of this approach by relating a commonly cited indicator species, the red-backed salamander (Plethodon cinereus), to a typical latent process of interest – ecosystem health.
Papers & Reports Climate’s cascading effects on disease, predation, and hatching success in Anaxyrus canorus, the threatened Yosemite toad
Authors: W J Sadinski; A L Gallant; J Cleaver
Date: 2020-09-01 | Outlet: Global Ecology and Conservation
The U.S. Fish and Wildlife Service listed Anaxyrus canorus, the Yosemite toad, as federally threatened in 2014 based upon reported population declines and vulnerability to global-change factors. A. canorus lives only in California’s central Sierra Nevada at medium to sub-alpine elevations. Lands throughout its range are protected from development, but climate and other global-change factors potentially can limit populations. A. canorus reproduces in ultra-shallow wetlands that typically hydrate seasonally via melting of the winter snowpack. Lesser snowpacks in drier years can render wetland water volumes and hydroperiods insufficient to allow for successful breeding and reproduction. Additionally, breeding and embryogenesis occur very soon after wetlands thaw when overnight temperatures can be below freezing. Diseases, such as chytridiomycosis, which recently decimated regional populations of ranid species, also might cause declines of A. canorus populations. However, reported studies focused on whether climate interacts with any pathogens to affect fitness in A. canorus have been scarce. We investigated effects of these factors on A. canorus near Tioga Pass from 1996 to 2001. We found breeding subpopulations were distributed widely but inconsistently among potentially suitable wetlands and frequently consisted of small numbers of adults. We occasionally observed small but not alarming numbers of dead adults at breeding sites. In contrast, embryo mortality often was notably high, with the majority of embryos dead in some egg masses while mortality among coincidental Pseudacris regilla (Pacific treefrog) embryos in deeper water was lower. After sampling and experimentation, we concluded that freezing killed A. canorus embryos, especially near the tops of egg masses, which enabled Saprolegnia diclina (a water mold [Oomycota]) to infect and then spread through egg masses and kill more embryos, often in conjunction with predatory flatworms (Turbellaria spp.). We also concluded exposure to ultraviolet-B radiation did not play a role. Based upon our assessments of daily minimum temperatures recorded around snow-off during years before and after our field study, the freezing potential we observed at field sites during embryogenesis might have been commonplace beyond the years of our field study. However, interactions among snow quantity, the timing of snow-off, and coincidental air temperatures that determine such freezing potential make projections of future conditions highly uncertain, despite overall warming trends. Our results describe important effects from ongoing threats to the fitness and abundance of A. canorus via reduced reproduction success and demonstrate how climate conditions can exacerbate effects from pathogens to threaten the persistence of amphibian populations.
Papers & Reports Time-to-detection occupancy methods: performance and utility for improving efficiency of surveys
Authors: Brian J Halstead; Jonathan P Rose; Patrick M Kleeman
Date: 2020-11-25 | Outlet: Ecological Applications
Occupancy methods propelled the quantitative study of species distributions forward by separating the observation process, or the imperfect detectability of species, from the ecological processes of interest governing species distributions. Occupancy studies come at a cost, however: the collection of additional data to account for nondetections at sites where the species is present. The most common occupancy designs (repeated measures designs) require repeat visits to sites or the use of multiple observers or detection methods. Time-to-detection methods have been identified as a potentially efficient alternative, requiring only one visit to each site by a single observer. A comparison of time-to-detection methods to repeated measures designs for visual encounter surveys would allow researchers to evaluate whether time-to-detection methods might be appropriate for their study system and can inform optimal survey design. We collected time-to-detection data during two different repeated measures design occupancy surveys for four amphibians and compared the performance of time-to-detection methods to the other designs using the location (potential bias) and precision of posterior distributions for occurrence parameters. We further used results of time-to-detection surveys to optimize survey design. Time-to-detection methods performed best for species that are widespread and have high detection probabilities and rates, but performed less well for cryptic species with lower probability of occurrence or whose detection was strongly affected by survey conditions. In all cases single surveys were most efficient in terms of person-hours expended, but under some conditions the survey duration required to achieve high detection probabilities would be prohibitively long for a single survey. Regardless of occupancy survey design, time-to-detection methods provide important information that can be used to optimize surveys, allowing researchers and resource managers to efficiently achieve monitoring and conservation goals. Collecting time-to-detection data while conducting repeated measures occupancy surveys requires only small modifications to field methods but could have large benefits in terms of time spent surveying in the long-term.
Papers & Reports Multi-Taxa Database Data Dictionary
Authors: E Watson; C J Rochester; C W Brown; D Holmes; S A Hathaway; R N Fisher
Date: 2021-02-09 | Outlet: U.S. Geological Survey Techniques and Methods 16-B1, 149 p.
The conservation of biological resources relies on the successful management of ecological and physiological research data. The Western Ecological Research Center of the U.S. Geological Survey is working with researchers, land managers and decision makers from non-government organizations, and city, county, state and federal resource agencies to develop data management methods. Access to the most current and applicable research data available in making sound decisions to conserve species diversity is foundational. We sought to accomplish several goals in developing the data management strategy used in the Multi-Taxa database (MTX). Data persistence and availability are primary goals of well-developed databases. By documenting and sharing the structure and definitions of MTX, we hope to further the successful management of these crucial data.
Papers & Reports Estimation of metademographic rates and landscape connectivity for a conservation-reliant anuran
Authors: Adam Duarte; J T Peterson; C A Pearl; J C Rowe; B McCreary; S Galvan; M J Adams
Outlet: Landscape Ecology
Context Amphibian conservation efforts commonly assume populations are tied to waterbodies that collectively function as a metapopulation. This assumption is rarely evaluated, and there is a need to understand the degree of connectivity among patches to appropriately define, manage, and conserve biological populations.

Objectives Our objectives were to quantify local persistence, colonization, and recruitment (metademographic rates) in relation to habitat attributes, evaluate the influence of the spatial arrangement of patches on landscape-scale population dynamics, and estimate the scale at which metapopulation dynamics are occurring for the Oregon spotted frog (Rana pretiosa).

Methods We collected R. pretiosa detection/non-detection data and habitat information from 93 sites spread throughout the species’ core extant range in Oregon, USA, 2010–2018. We developed a spatial multistate dynamic occupancy model to analyze these data.

Results Results indicated the proportion of sites occupied by R. pretiosa was relatively stable despite regular turnover in site occupancy. Connectivity was highest when the distance between sites was within 4.49–7.70 km, and populations within 1 km are at the appropriate spatial scale for effective population management. Rana pretiosa metademographic rates were strongly tied to water availability, vegetation characteristics, and beaver dams.

Conclusions Our analysis provides critical information to identify the appropriate spatial scale for effective population management, estimates the distance at which populations are connected, and quantifies the effects of hypothesized threats to species at a landscape scale. We believe this type of model can inform conservation and management strategies for multiple species.
Papers & Reports Changes in capture rates and body size among vertebrate species occupying an insular urban habitat reserve
Authors: T R Stanley; R W Clark; R N Fisher; C J Rochester; S A Root; K J Lombardo; S D Ostermann-Kelm
Date: 2020-06-29 | Outlet: Conservation Science and Practice 2020;e245.
Long-term ecological monitoring provides valuable and objective scientific information to inform management and decision making. In this paper we analyze 22 years of herpetofauna monitoring data from the Point Loma Ecological Conservation Area (PLECA), an insular urban reserve near San Diego, California. Our analysis showed that counts of individuals for one of the four most common terrestrial vertebrates declined, whereas counts for other common species increased or remained stable. Two species exhibited declines in adult body length, whereas biomass pooled over the five most common species increased over time and was associated with higher wet season precipitation. Although the habitat and vegetation at PLECA have remained protected and intact, we suspect that changes in arthropod communities may be driving changes in the abundance, growth, and development of insectivorous lizards. This study underscores the value of long-term monitoring for establishing quantitative baselines to assess biological changes that would otherwise go undetected.
Papers & Reports Herpetofauna of the cedar glades and associated habitats of the Inner Central Basin of Middle Tennessee
Authors: Mathew L Niemiller; R G Reynolds; B M Glorioso; J Spiess; B T Miller
Date: 2011 | Outlet: Herpetological Conservation and Biology6(1):127-141
The cedar glades and barrens of the Inner Central Basin (ICB) of middle Tennessee support a unique and diverse flora and fauna and represent some of the state’s most valued natural areas. We conducted herpetofaunal inventories of the cedar glades, associated barrens, cedar-hardwood forest, and adjacent aquatic habitats of the Stones River drainage of Middle Tennessee, focusing our sampling effort primarily at seven state- or federally owned properties in Rutherford and Wilson counties. These properties included Stones River National Battlefield (SRNB), Flat Rock State Natural Area (FRSNA), Vesta Cedar Glade State Natural Area (VSNA), Fall Creek Recreation Area (FCRA) on J. Percy Priest Wildlife Management Area, Cedars of Lebanon State Forest (CLSF), Cedars of Lebanon State Forest Natural Area (CLSNA), and Cedars of Lebanon State Park (CLSP). We used a variety of inventory techniques in terrestrial, aquatic, and subterranean habitats to survey these properties periodically from 1989 to 2010. We documented 49 species (22 amphibian and 27 reptile) accounting for 75.4% of the 65 herpetofaunal species thought to occur in the ICB, including records for Cemophora coccinea, Aneides aeneus, Gyrinophilus palleucus, Ambystoma barbouri, and Pseudotriton montanus. We found differences in alpha and beta diversity between sites, with the CLSF complex containing a high of 41 herpetofaunal species and FRSNA containing a low of 23 species. Beta diversity comparisons indicated similarity in amphibian species composition between FRSNA and CLSF and between SRNB and CLSF (9 shared species), and in reptile species composition between VSNA and the CLSF complex (16 shared species). We compare the results of our inventory with two previous studies conducted in the area and discuss the relative abundance, conservation, and threats to the herpetofaunal community of these habitats.
Papers & Reports A trapping survey targeting head-started alligator snapping turtles in southwest Louisiana
Authors: B M Glorioso; L J Muse; C J Hillard; B R Maldonado; J Streeter; C D Battaglia; J Hardin Waddle
Date: 2020 | Outlet: Journal of Fish and Wildlife Management
Papers & Reports Survival estimates for the invasive American Bullfrog
Authors: P E Howell; Erin Muths; Brent H Sigafus; Blake R Hossack
Outlet: Amphibia-Reptilia
We used five years of capture mark-recapture data to estimate annual apparent survival of post-metamorphic bullfrogs in a population on the Buenos Aires National Wildlife Refuge in their invaded range in Arizona, U.S.A.