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Roel R. Lopez

Publications and source records attributed to Roel R. Lopez.

2 recordsLinked to original sources

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

Using a multi-model ensemble approach to determine biodiversity hotspots with limited occurrence data in understudied areas: An example using freshwater mussels in México

Species distribution models (SDMs) are an increasingly important tool for conservation particularly for difficult-to-study locations and with understudied fauna. Our aims were to (1) use SDMs and ensemble SDMs to predict the distribution of freshwater mussels in the Pánuco River Basin in Central México; (2) determine habitat factors shaping freshwater mussel occurrence; and (3) use predicted occupancy across a range of taxa to identify freshwater mussel biodiversity hotspots to guide conservation and management. In the Pánuco River Basin, we modeled the distributions of 11 freshwater mussel species using an ensemble approach, wherein multiple SDM methodologies were combined to create a single ensemble map of predicted occupancy. A total of 621 species-specific observations at 87 sites were used to create species-specific ensembles. These predictive species ensembles were then combined to create local diversity hotspot maps. Precipitation during the warmest quarter, elevation, and mean temperature were consistently the most important discriminatory environmental variables among species, whereas land use had limited influence across all taxa. To the best of our knowledge, our study is the first freshwater mussel-focused research to use an ensemble approach to determine species distribution and predict biodiversity hotspots. Our study can be used to guide not only current conservation efforts but also prioritize areas for future conservation and study.

Pánuco