Skip to main content
Dryad

Data from: swimming through sand: using accelerometers to observe the cryptic, pre-emergence life-stage of sea turtle hatchlings

Dor, Davey1; Booth, David2; Schwanz, Lisa1

Published Aug 21, 2024 on Dryad. https://doi.org/10.5061/dryad.c866t1gdd

Data files

Aug 21, 2024 version files 33.14 KB

Abstract

Animals that hatch within a subterranean nest, such as turtle hatchlings, expend some of their limited energy reserves digging out through sand or soil to reach the surface. In sea turtles, this emergence process can take the hatchlings 3 – 7 days. However, we have a poor understanding of this process as it is difficult to observe what is occurring underground. Here we utilize a novel method to characterise digging-out behaviour: affixing an accelerometer directly to newly hatched green turtles (Chelonia mydas) to record movement until nest emergence. Our data revealed that buried hatchlings maintained a head-up orientation, but did not move in the expected left and right swaying motion associated with alternating limb crawling. Rather, they moved using dorsal-ventral heaving and pitching as if swimming vertically through the sand to the surface. Movement activity was irregular and brief, interspersed by many short periods of inactivity, mostly lasting less than 10 minutes. The first 24-hours of head-up activity displayed no diel patterns, but the last 24-hours prior to emergence involved more intense movement during nighttime hours compared with daytime hours. Thus, our results add valuable new insight, and in some cases change previous assumptions, regarding the digging behaviours during the egg-to-emergence life stage in sea turtles.