Fleming Kelsey A, Perrault Justin R, Stacy Nicole I, Coppenrath Christina M, Gainsbury Alison M
Department of Biological Sciences, University of South Florida St. Petersburg, St. Petersburg, FL 33701, USA.
Loggerhead Marinelife Center, Juno Beach, FL 33408, USA.
Conserv Physiol. 2020 Jun 3;8(1):coaa046. doi: 10.1093/conphys/coaa046. eCollection 2020.
Incubation temperatures, in addition to an embryo's genetic makeup, are critical in many aspects of adequate sea turtle embryonic development. The effects of high and low incubation temperatures on hatchling quality have been previously examined; however, many of these studies were conducted on relocated or laboratory-reared nests, which do not accurately reflect natural nest temperature fluctuations. To observe the impacts of varying incubation temperatures on loggerhead sea turtle () hatchling morphology, various health variables and locomotor performance, temperature data loggers were deployed in 15 loggerhead nests on Juno Beach, Florida, between May and July 2018. Over the course of the study period, 10 morphological traits were measured, blood analytes and heart rate were assessed for the establishment of reference intervals and the self-righting response in seawater was evaluated. Warmer months were associated with smaller body size and higher body condition index, larger umbilical scar size, slower righting time, lower heart rates and higher packed cell volume, hemoglobin, total solids, total white blood cell count, absolute heterophils and absolute basophils. These findings provide evidence that higher incubation temperatures have the potential to adversely affect hatchlings from warmer nests due to increased risk of predation from smaller body sizes, decreased physical responses and overall fitness, altered hemodynamic balance (e.g. dehydration) and potential inflammation and/or stress. With rising temperatures, we predict sea turtle hatchlings may have increasing risks of developing suboptimal physiological features affecting overall fitness and ultimately survival. These results demonstrate that rising environmental temperatures can negatively impact sea turtle hatchlings, thus representing additional stress on sea turtle populations and contributing to our understanding of potential pathophysiological effects of climate change on the delicate life-stage class of the sea turtle hatchling. This information will be useful for formulating effective future sea turtle management plans.
孵化温度，除了胚胎的基因组成外，在海龟胚胎充分发育的许多方面都至关重要。先前已经研究了高、低孵化温度对幼龟质量的影响；然而，这些研究大多是在重新安置或实验室饲养的巢穴上进行的，这些并不能准确反映自然巢穴温度的波动。为了观察不同孵化温度对蠵龟幼龟形态、各种健康变量和运动性能的影响，2018年5月至7月期间，温度数据记录器被部署在佛罗里达州朱诺海滩的15个蠵龟巢穴中。在研究期间，测量了10个形态特征，评估了血液分析物和心率以建立参考区间，并评估了在海水中的自行扶正反应。较温暖的月份与较小的体型、较高的身体状况指数、较大的脐部疤痕尺寸、较慢的扶正时间、较低的心率以及较高的红细胞压积、血红蛋白、总固体、白细胞总数、绝对嗜中性粒细胞和绝对嗜碱性粒细胞有关。这些发现提供了证据，表明较高的孵化温度可能会对来自较温暖巢穴的幼龟产生不利影响，原因是体型较小增加了被捕食的风险、身体反应和整体健康状况下降、血液动力学平衡改变（如脱水）以及潜在的炎症和/或应激。随着温度升高，我们预测海龟幼龟可能有越来越大的风险出现影响整体健康并最终影响生存的次优生理特征。这些结果表明，环境温度升高会对海龟幼龟产生负面影响，从而给海龟种群带来额外压力，并有助于我们理解气候变化对海龟幼龟这一脆弱生命阶段潜在的病理生理影响。这些信息将有助于制定未来有效的海龟管理计划。
