Data and code supporting acoustic and environmental factors driving digging behavior in the early life of a freshwater turtle

Acoustic communication is widespread in the animal kingdom and often fundamental to early life survival. Extant archosaurs, birds and crocodilians, display complex vocalizations in early life that function in parental care and embryo communication. Turtles are a sister group to archosaurs, and vocalize, but lack parental care, providing an opportunity to decouple parental care from other factors driving the evolution of neonatal communication. Turtle hatchlings produce vocalizations in the subterranean nest before emergence, but their function remains unclear. We hypothesized that acoustic cues may facilitate emergence from the nest by cuing hatchlings to begin digging out of the subterranean nest cavity. We test whether hatchling vocalizations are positively associated with digging activity in hatchling snapping turtles (Chelydra serpentina). In two successive years, we monitored subterranean hatchling behaviour in situ with acoustic recorders in semi-natural turtle nests. Structural Equation Modelling revealed that vocalization was causally associated with hatchling movement. Our findings support a hypothesis that early-life acoustic communication coordinates a social activity in the absence of parental care, a function with relatively few described parallels in the animal kingdom.