Effect of Hatchery Nest Environment on Olive Ridley (Lepidochelys olivacea) Hatchling Performance

Abstract

The nest environment plays an important role in influencing sea turtle hatchling phenotype. Increasing global temperatures can potentially cause detrimental changes to hatchling size and performance and ultimately influence their recruitment into the adult population. The mass nesting rookeries of olive ridleys in Odisha on the east coast of India are among the largest globally and the only major ones outside Central America. Many nests laid on the east coast of India are translocated to hatcheries as part of hatchery management practices. Therefore, it is imperative to understand the effects of temperature on hatchlings produced in hatcheries as well as site-specific factors in order to undertake appropriate climate-resilient hatchery management measures. This study examined the effect of temperature on the morphology and locomotor performance of hatchlings produced in 2 different hatcheries on the east coast: in Rushikulya, Odisha, and in Chennai, Tamil Nadu, India. We examined various size (body, flipper, and neck length) and performance (crawl speed, righting ability, and righting propensity) parameters for hatchlings at both hatcheries across a range of temperatures. We found that hatchling size and performance were significantly influenced by nest incubation temperature. Higher incubation temperatures resulted in smaller hatchling size, which in turn was correlated with lower performance variables. Incubation temperature also had a direct effect on hatchling performance independent of hatchling size. The effect of nest temperature on morphology and performance of hatchlings could influence their survival and recruitment rates, thus influencing population dynamics and resilience to climate change.