Geology topics

Max D. Jones

Publications and source records attributed to Max D. Jones.

4 recordsLinked to original sources

USGS2026

Boxed in or branching out? Movement and resource selection of eastern box turtles (Terrapene carolina carolina) in an urban green space

The eastern box turtle ( Terrapene carolina carolina ) is a long-lived terrestrial turtle species distributed throughout the eastern United States that has experienced widespread population decline. Many eastern box turtle populations are persisting as remanent populations in small, fragmented urban green spaces. We investigated the movement and resource selection of eastern box turtles within a mid-Atlantic region urban forest in the eastern United States. We used a combination of turtle occurrence data (via visual encounter surveys) and radio telemetry to create resource selection functions. Additionally, we applied a simulation modeling approach and modeled activity areas via dynamic Brownian Bridge Movement Models to quantify interactions between turtles and roads or trails. We also used these models to determine the propensity for turtles to move outside of the managed urban forest boundary and into surrounding development. We observed that turtles selected for deciduous forest patches and avoided roads and trails despite the urban forest having very little available areas where anthropogenic features could be avoided. We also demonstrated observed (and probable) movements outside of the urban forest boundary. Although eastern box turtles are persisting within the urban green space we examined, our work determined that interactions with roads and trails, and movements outside of protected boundaries into developed areas present challenges to individuals navigating the urban forest.

eastern United States, mid-Atlantic region↗

USGS2025

Aggregated space use by soft-released translocated Gopher Tortoises (Gopherus polyphemus)

Translocated herpetofauna can exhibit irregular space use and movement patterns when compared with resident conspecifics. In Florida, USA, Gopher Tortoises ( Gopherus polyphemus ) are translocated throughout the state to mitigate habitat loss due to development. The postrelease space use of translocated Gopher Tortoises within soft-release pens can affect population dynamics and population monitoring efficacy, and understanding spatial patterns can aid wildlife managers with population management. We used a combination of time-lapse cameras, animal tracking devices, and burrow distribution surveys to investigate translocated tortoise space use at Eglin Air Force Base, Florida, where tortoises have been translocated since 2015. We investigated 10 soft-release pens that varied in size (4–41 ha) and shape (due to landscape configuration and existing infrastructure). Time-lapse cameras and burrow distribution surveys showed that tortoises used habitat within 20 m of soft-release pens (silt fences) significantly more than the interior of pens. In most pens, the selection of pen-edge habitat resulted in a clustering effect that lessened upon subsequent surveys, after fences were removed. Additionally, our tracking data showed mixed evidence for clustering, where three of the seven tortoises used edge area significantly more than the interior of pens. Such clustering can affect the efficacy of population survey methods while potentially having negative impacts on the health of translocatees by increasing local density.

Florida↗

USGS2024

A multi-objective approach for timber harvest scheduling to include management of at-risk species and spatial configuration objectives

Sustainable forestry typically involves integration of several economic and ecological objectives which, at times, may not be compatible with one another. Multi-objective prioritization via harvest scheduling programs can be used to elucidate these relationships and explore solutions. One such program is a spatially explicit harvest scheduler that adopts the Metropolis-Hastings algorithm to iteratively find management solutions to achieve multiple objectives (Habplan). Although this program has been used to address forest management scheduling and simulation-based tasks, its utility is constrained by time-intensive data preparation and challenges with incorporating spatial configuration objectives. To address these shortcomings, we introduce an open-source software package, HabplanR, streamlines data preparation, sets parameters, visualizes results, and assesses spatial components of ecological objectives. We developed four example objectives to incorporate into a multi-objective management problem: habitat quality indices for three species “types” (open, closed, and intermediate-canopy-associated species), and harvested pine pulpwood (revenue). We demonstrate the utility of this package to find management schedules that can accommodate potentially conflicting habitat needs of species, while achieving economic targets. We produced 100 software runs and prioritized individual objectives to select four management schedules for further comparisons. We compared outcome differences of the four schedules, including a spatial comparison of two high performing schedules. The software package makes costs and benefits of different schedules explicit and allows for consideration of the spatial configuration of management outcomes in decision-making.

southeastern United States↗

USGS2024

Simulation modeling to assess line transect distance sampling under a range of translocation scenarios

The accuracy of posttranslocation population monitoring methods is critical to assessing long-term success in translocation programs. Translocation can produce unique challenges to monitoring efforts; therefore, it is important to understand the flexibility and robustness of commonly used monitoring methods. In Florida, USA, thousands of gopher tortoises Gopherus polyphemus have been, and continue to be, translocated from development sites to permitted recipient sites. These recipient sites create a broad range of potential monitoring scenarios due to variability in soft-release strategies, habitat conditions, and population demographics. Line transect distance sampling is an effective method for monitoring natural tortoise populations, but it is currently untested for translocated populations. We therefore produced 3,024 individual-based, spatially explicit scenarios of translocated tortoise populations that differed in recipient site and tortoise population properties, based on real-world examples, literature review, and expert opinion. We virtually sampled simulated tortoise populations by using line transect distance sampling methods and built a Bayesian hierarchical model to estimate the population density for each simulation, which incorporated individual-level covariates (i.e., burrow width and burrow occupancy). Line transect distance sampling was largely appropriate for the conditions that typify gopher tortoise recipient sites, particularly when detection probability on the transect lines was greater than or equal to 0.85. Designing the layout of transects relative to the orientation of soft-release pens, to avoid possible sampling biases that lead to extreme outliers in estimates of tortoise densities, resulted in more accurate population estimates. We also suggest that use of individual-level covariates, applied using a Bayesian framework as demonstrated in our study, may improve the applicability of line transect distance sampling surveys in a variety of contexts and that simulation can be a powerful tool for assessing survey design in complex sampling situations.

Florida↗