Geology topics

Anthony Tur

Publications and source records attributed to Anthony Tur.

7 recordsLinked to original sources

USGS2026

Range-wide relative abundance of the Appalachian grizzled skipper ( Pyrgus centaureae wyandot ) in the Eastern United States

The U.S. Fish and Wildlife Service has designated the Pyrgus centaureae wyandot (Appalachian Grizzled Skipper [AGS]) to be at-risk, based on its declining populations and the lack of information on its status. The objective of this study was to complete range-wide surveys to locate extant AGS colonies and to quantify the number of AGS observed at each location. From 2021–24, 284 surveys were done in 25 unique (that is, distinct) counties in 8 States in the Eastern United States — Maryland, Michigan, New York, North Carolina, Ohio, Pennsylvania, Virginia, and West Virginia. We found AGS in only two counties: Alleghany County, Virginia, and Greenbrier County, West Virginia. AGS were observed 180 times in these two counties. Our results can inform U.S. Fish and Wildlife decisions about where and how future AGS conservation efforts can be implemented.

Maryland, Michigan, New York, North Carolina, Ohio↗

USGS2026

Range-wide relative abundance of Pyrgus centaureae wyandot (W.H. Edwards, 1863) (Appalachian Grizzled Skipper)

The US Fish and Wildlife Service has designated the butterfly Pyrgus centaureae wyando t (Appalachian Grizzled Skipper [AGS]) to be at-risk, based on its declining populations and the lack of information on its status. Our objective was to conduct range-wide surveys to locate extant AGS colonies and to quantify the number of AGS observed at each location. From 2021 to 2024, we conducted 284 surveys in 25 unique (i.e., distinct) counties in 8 states (Maryland, Michigan, New York, North Carolina, Ohio, Pennsylvania, Virginia, and West Virginia). We found AGS in only 2 counties: Alleghany County, VA, and Greenbrier County, WV. AGS were observed 180 times in these counties. Our results can inform US Fish and Wildlife decisions about where and how future AGS conservation efforts can be implemented.

Northeastern Naturalists↗

USGS2025

Quantifying the relative importance of survival threats to a long-lived reptile using expert elicitation

Long-term survival of a conservation-reliant species requires understanding the impact of threats on population growth rate and the management actions that can help mitigate these threats. We used a threat assessment with expert-elicited estimates to determine the relative effect of each stage-specific threat on the population growth rate of the wood turtle Glyptemys insculpta . In addition, we offered potential management actions that could mitigate these threats and examined the relative cost and benefit of each. The experts responded that predators had the largest effect on hatchling and juvenile survival and that road mortality had the largest effect on adult survival. The population growth rate of the simulated turtle population increased the most when predators were removed from the system, though the population trajectory remained negative. Finally, we found that predator control had the lowest cost:benefit ratio of the proposed management actions. The process used in this analysis of expert elicitation combined with modeling that accounts for uncertainty proved to be a useful technique that is less expensive and labor intensive than empirical studies and quicker to implement, although it relies on sufficient empirical studies to inform expert responses. This process could be replicated for other species to inform species status assessments.

Endangered Species Research↗

USGS2024

Long-term monitoring reveals management effects on Prairie Warbler colonization, local extinction, and detection in a Massachusetts pine barren

Habitat management can directly impact Setophaga discolor (Prairie Warbler) abundance and distribution. Despite regional declines, Prairie Warbler populations at Camp Edwards (Bourne, MA) have increased. To investigate habitat-management effects on Prairie Warbler populations at Camp Edwards, we used a dynamic-occupancy model to analyze a long-term monitoring dataset collected across 84 point-count sites from 2013 to 2022. The model results indicated that Prairie Warbler colonization and extinction probabilities were impacted by management (measured in years since disturbance). Colonization probability was highest initially after disturbance, then subsequently decreased for ∼50 years, and extinction probability also decreased for ∼25 years. Both probabilities remained low before increasing at ∼75 years since disturbance. The increase in colonization probability >75 years since disturbance may have been an artifact of our study design and incomplete disturbance records. We also found that latitude and longitude significantly affected colonization probability, likely a result of how habitat types are distributed across the base. These results inform how Prairie Warblers respond to long-term management, suggesting that habitat management could improve colonization rates and sustain Prairie Warbler populations.

Massachusetts↗

USGS2024

The effect of myiasis on Eastern Box Turtle (Terrapene carolina carolina) body condition, movement, and habitat use at Camp Edwards in Massachusetts

In 2020, natural resource managers at Camp Edwards, Barnstable County, MA, observed Terrapene carolina carolina (Eastern Box Turtle) individuals infected by myiasis, where parasitic flesh flies larviposit into the living tissue of a host. The hypothesized parasite was Dexosarcophaga cistudinis, but its impacts on the host's body condition, movement, and habitat use were unknown. Our objectives were to identify the parasite at Camp Edwards and to compare the body condition, movement, and habitat characteristics at capture locations of Eastern Box Turtles for infected and noninfected individuals. We radio-tracked turtles weekly and encountered 48 individuals from May to August 2022 at Camp Edwards, MA. Upon capture, we recorded turtle infection status, mass, carapace length, shell surface temperature, GPS location, and habitat characteristics of the capture location. We confirmed D. cistudinis as the parasite and found that myiasis-infected turtles had a significantly higher shell temperature (27.92 ± 5.28 °C) than noninfected turtles (26.77 ± 5.64 °C). However, we did not find an effect of myiasis on body condition, habitat use, or average daily distance moved. Collectively, our results suggest that infected turtles may exhibit behavioral fever, a mechanism by which ectotherms move to warmer microclimates to raise their body temperature in response to infections. Eastern Box Turtles at Camp Edwards may be able to use behavioral fever in response to myiasis infection because of the habitat mosaic made available through detailed habitat-management regimes.

Massachusetts↗

USGS2022

Evaluating the effect of expert elicitation techniques on population status assessment in the face of large uncertainty

Population projection models are important tools for conservation and management. They are often used for population status assessments, for threat analyses, and to predict the consequences of conservation actions. Although conservation decisions should be informed by science, critical decisions are often made with very little information to support decision-making. Conversely, postponing decisions until better information is available may reduce the benefit of a conservation decision. When empirical data are limited or lacking, expert elicitation can be used to supplement existing data and inform model parameter estimates. The use of rigorous techniques for expert elicitation that account for uncertainty can improve the quality of the expert elicited values and therefore the accuracy of the projection models. One recurring challenge for summarizing expert elicited values is how to aggregate them. Here, we illustrate a process for population status assessment using a combination of expert elicitation and data from the ecological literature. We discuss the importance of considering various aggregation techniques, and illustrate this process using matrix population models for the wood turtle ( Glyptemys insculpta ) to assist U.S. Fish and Wildlife Service decision-makers with their Species Status Assessment. We compare estimates of population growth using data from the ecological literature and four alternative aggregation techniques for the expert-elicited values. The estimate of population growth rate based on estimates from the literature (λ mean = 0.952, 95% CI: 0.87–1.01) could not be used to unequivocally reject the hypotheses of a rapidly declining population nor the hypothesis of a stable, or even slightly growing population, whereas our results for the expert-elicited estimates supported the hypothesis that the wood turtle population will decline over time. Our results showed that the aggregation techniques used had an impact on model estimates, suggesting that the choice of techniques should be carefully considered. We discuss the benefits and limitations associated with each method and their relevance to the population status assessment. We note a difference in the temporal scope or inference between the literature-based estimates that provided insights about historical changes, whereas the expert-based estimates were forward looking. Therefore, conducting an expert-elicitation in addition to using parameter estimates from the literature improved our understanding of our species of interest.

Journal of Environmental Management↗

USGS2017

Microsatellite marker development from next-generation sequencing in the New England cottontail (Sylvilagus transitionalis) and cross-amplification in the eastern cottontail (S. floridanus)

Objective The New England cottontail ( Sylvilagus transitionalis ) is a species of high conservation priority in the Northeastern United States, and was a candidate for federal listing under the Endangered Species Act until a recent decision determined that conservation actions were sufficient to preclude listing. The aim of this study was to develop a suite of microsatellite loci to guide future research efforts such as the analysis of population genetic structure, genetic variation, dispersal, and genetic mark-recapture population estimation. Results Thirty-five microsatellite markers containing tri- and tetranucleotide sequences were developed from shotgun genomic sequencing of tissue from S. transitionalis , S. obscurus , and S. floridanus . These loci were screened in n = 33 wild S. transitionalis sampled from a population in eastern Massachusetts, USA. Thirty-two of the 35 loci were polymorphic with 2–6 alleles, and observed heterozygosities of 0.06–0.82. All loci conformed to Hardy–Weinberg Equilibrium proportions and there was no evidence of linkage disequilibrium or null alleles. Primers for 33 of the 35 loci amplified DNA extracted from n = 6 eastern cottontail ( S. floridanus ) samples, of which nine revealed putative species-diagnostic alleles. These loci will provide a useful tool for conservation genetics investigations of S. transitionalis and a potential diagnostic species assay for differentiating sympatric eastern and New England cottontails.

Massachusetts↗