Incubation temperature effects on hatchling performance in the loggerhead sea turtle (Caretta caretta)

• Published in: PloS one 2014-12, Vol.9 (12), p.e114880
• Main Authors: Fisher, Leah R, Godfrey, Matthew H, Owens, David W
• Format: Article
• Language: English
• Subjects: Animals; Apalone mutica; Aquatic reptiles; Beaches; Biology; Biology and Life Sciences; Caretta caretta; Chelonia mydas; Cheloniidae; Chelydra serpentina; Climate change; Ecology and Environmental Sciences; Eggs; Elusor macrurus; Eretmochelys imbricata; Experiments; Females; Genotype & phenotype; Global temperature changes; High temperature; Incubation; Influence; Juveniles; Lepidochelys olivacea; Natator depressus; Ovum - physiology; Population; Reproduction; Reptiles & amphibians; Reptilia; Research and Analysis Methods; Response time; Righting reflex; Righting response; Sea turtles; Sex differentiation; Studies; Survival; Survival Analysis; Temperature; Temperature effects; Turtles - physiology
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0114880

Incubation temperature has significant developmental effects on oviparous animals, including affecting sexual differentiation for several species. Incubation temperature also affects traits that can influence survival, a theory that is verified in this study for the Northwest Atlantic loggerhead sea turtle (Caretta caretta). We conducted controlled laboratory incubations and experiments to test for an effect of incubation temperature on performance of loggerhead hatchlings. Sixty-eight hatchlings were tested in 2011, and 31 in 2012, produced from eggs incubated at 11 different constant temperatures ranging from 27°C to 33°C. Following their emergence from the eggs, we tested righting response, crawling speed, and conducted a 24-hour long swim test. The results support previous studies on sea turtle hatchlings, with an effect of incubation temperature seen on survivorship, righting response time, crawling speed, change in crawl speed, and overall swim activity, and with hatchlings incubated at 27°C showing decreased locomotor abilities. No hatchlings survived to be tested in both years when incubated at 32°C and above. Differences in survivorship of hatchlings incubated at high temperatures are important in light of projected higher sand temperatures due to climate change, and could indicate increased mortality from incubation temperature effects.