Influences of the Local Climate on Loggerhead Hatchling Production in North Florida: Implications From Climate Change

Abstract

The environment and climate in which sea turtle eggs incubate affects how successful and viable hatchlings are. Therefore, it is crucial to understand how local climate impacts sea turtle hatchling production as well as how potential changes in climate may impact future hatchling production. In this study, we investigated the effects of five climate variables at different temporal scales on loggerhead sea turtle (Caretta caretta) hatchling production from North Florida, USA. Humidity, air temperature, and accumulated precipitation were the main climatic drivers of hatchling production, while sea surface temperature and wind speed did not demonstrate to have strong effects. Climate projections show air temperatures increasing at the nesting beaches throughout the 21st century, while precipitation and humidity projections vary between sites and projection scenarios. Due to the temperate nature of these nesting beaches, increases in hatching success for nests that incubate undisturbed (not affected by depredation and storm-related impacts) are projected for this region by 2100. This study demonstrates how different climate variables and their interactions can have a determining effect on an important marine species.

Plastic pollution can affect the emergence patterns of loggerhead turtle hatchlings

“…In the absence of explicit scientific conclusions to elucidate the reasons for such impacts, we propose two distinct hypotheses. Plastics might change the substrate humidity and water‐holding capacity (Souza Machado et al ., 2018; Wan et al ., 2019), very important aspects in the successful production of hatchlings (Montero et al ., 2018; Gravelle & Wyneken, 2022): high humidity may promote fungal growth (Sarmiento‐Ramírez et al ., 2010; Gleason, Allerstorfer, & Lilje, 2020), whereas low humidity may lead to egg desiccation (Carson et al ., 2011). However, it is unlikely that alterations in the sand water content directly affect the emergence patterns.…”

Caretta caretta nesting activity on Akumal Beaches, Mexico

“…Temperatures above 31 °C may impact the hatchling survivorship rate 25 , which probably explains why some ES values were so low. Humidity, air temperature, and precipitation are probably the main climatic drivers of hatchling production; sea surface temperature and wind speed, though important, do not have significant influences 27 . It would be very important to determine, for example, the temperature fluctuations in Akumal sand/ nests to understand how they affect incubation conditions (are they female-biased with an increasing trend?…”

Sea turtle conservation as a blueprint for freshwater turtles in the eastern U.S.

“…Climate change is also expected to affect species distribution (Patel et al, 2021;Fuentes et al, 2020), foraging success and breeding phenology (Lettrich et al, 2020;Hawkes et al, 2009). Sea level rise, warmer temperatures, more extreme precipitation events and ocean acidification as modeled by the Intergovernmental Panel on Climate Change will put further pressure on sea turtle populations (Lettrich et al, 2020;IPCC, 2022), potentially causing increased preemergence mortality in more southern U.S. Atlantic nesting beaches (Montero et al, 2018). Continually rising and more frequent extreme sea levels, in particular, are expected to perpetuate beach erosion and decrease available nesting habitat for sea turtles and force them to nest closer to the water line (Lyons et al, 2020).…”