Biology subjects

Abreu-Grobois, F. A.

Publications and source records attributed to Abreu-Grobois, F. A..

3 recordsLinked to original sources

bioRxiv2026

Individual natal assignment in highly migratory species: the genomic baseline and its application in loggerhead turtles

O_LIEffective conservation of highly migratory species requires understanding genetic structure across breeding populations and access high{square}resolution markers capable of assigning individuals from mixed aggregates (e.g. bycatch or new nesting sites) to their natal origins. Genomic approaches provide unprecedented resolution but add methodological challenges; thus, it is essential to first build a genomic baseline from known breeding areas and then evaluate strategies for assigning unknown individuals. C_LIO_LITo address this, we used 2b-RAD sequencing, a genomic reduction technique useful for degraded DNA, and loggerhead turtles as a case study. This species shows philopatric breeding, while juveniles and adults form mixed aggregations in foraging grounds. C_LIO_LIOur results highlight the importance of building baselines that include all potential source populations contributing to mixed aggregations. We detected hierarchical genetic differentiation and high resolution and successfully assigned the natal origin of 124 unknown individuals from four Mediterranean foraging grounds. These grounds showed distinct source contributions, and comparisons with previous studies suggest possible temporal shifts in stock composition. C_LIO_LIWe provide a comprehensive genomic baseline for individual assignment of Altanto-Mediterranean loggerhead turtles of unknown natal origin and a general framework for identifying population-specific threats in highly migratory species. C_LI

evolutionary biology↗

bioRxiv2021

Integrating ecological monitoring and local ecological knowledge to evaluate conservation outcomes

Successful conservation of long-lived species requires reliable understanding of long-term trends and historical baselines. Using a green turtle (Chelonia mydas) foraging aggregation in the northern Gulf of California, Mexico as case study, we integrated scientific monitoring data with historic catch rate reconstructions derived from Local Ecological Knowledge (LEK). Models fit to LEK and monitoring data indicate that turtle abundance is increasing, but only after ~40 years of safeguarding the species nesting and foraging habitats in Mexico. However, as population declines occurred 75% faster than increases, and current abundance is at ~60% of historical baseline levels, indicating the need for sustained, long-term conservation actions. This study demonstrates the potential of linking LEK and ecological science to provide critical information for conservation, by establishing reference baselines and gauging population status, while promoting equitable and sustainable futures for local communities.

ecology↗

bioRxiv2019

Neglecting low season nest protection exacerbates female biased sea turtle hatchling production through the loss of male producing nests.

In the eastern Pacific, peak olive ridley sea turtle (Lepidochelys olivacea) nesting occurs during the warmest months which coincide with the rainy season, yet as nesting takes place year-round, the small proportion of the nests laid during dry-low season are exposed to contrasting environmental conditions. Most of the studies on Pacific coast sea turtles have estimated sex ratios produced during the rainy-high season when the majority of conservation activities take place. Thus, dry-low season nests have on the whole been overlooked. Here we compared sex ratios and hatchling fitness for offspring produced during the dry and rainy seasons during 2015. We found that protected olive ridley clutches incubated during the dry-low season were exposed to lower temperatures, yielded higher hatchling success, produced 100% male offspring and larger, heavier hatchlings with better locomotor abilities. Our results highlight the critical value of monitoring and protecting sea turtle nests beyond the peak season (when nests can be protected more efficiently) to include low season nests, albeit at much lower densities, but which by yielding higher proportions of males and with greater locomotor capacities may be the key to population viability and adaptation to anthropogenic climate change.

ecology↗