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Girondot, M.

Publications and source records attributed to Girondot, M..

2 recordsLinked to original sources

Performance of the sea turtle Lepidochelys olivacea hatchlings from a hatchery on the Pacific coast of Guatemala

Sea turtles are marine species that are generally in danger of extinction. The conservation strategies in the different countries are attempting to preserve these species and should be constantly updating their policies according to research results taking place on site. The most abundant and frequent species of sea turtle that nest in the Pacific Coast of Guatemala is Lepidochelys olivacea (Eschscholtz, 1829), therefore human predation has been historically high. The solution to this predation, since the 1970s, as a conservation strategy was to place eggs in enclosed protected spaces called hatcheries, where collectors must give 20% of the nest as a conservation quota. Since this program leads to no natural nests (in situ) remaining on the beaches, the good functioning of the hatcheries plays a fundamental role in the conservation process to work. To understand and predict the fitness of the hatchlings being produced in Guatemalan hatcheries, crawling performance and self-righting performance were measured in 210 hatchlings of the Multiple Uses Area of Hawaii, in the Pacific Coast of Guatemala. The results of the performance were contrasted with incubation conditions to provide an insight into how the management may influence it. We found that self-righting may be a more meaningful measure of variable behavior than crawling performance, showing that there was little variation due to the homogeneous environment of the hatcheries. We can conclude that a greater number of eggs result in faster self-righting, while deeper nests produce hatchlings with slower rates of self-righting. Summary statementWhen hatcheries are the only sea turtle conservation strategy, and their well-functioning is vital to achieve this purpose, performance can provide information of hatchlings fitness in response to management conditions.

ecology↗

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↗