Hirama, S. B. Witherington, S. Hirsch, A. Sylvia, and R. R. Carthy. 2023. Accuracy and precision of hatchling sea-finding orientation as a function of dune proximity in hatchlings of two species of sea turtles. Marine and Freshwater Research (IF 1.8) , DOI:10.1071/mf23052.
Abstract
Sea turtle hatchlings emerge at night from nests on sand beaches and immediately orient using visual cues. The purpose of this study was to understand how dune proximity (distance from nest to dune silhouette) affected hatchling orientation, and if differences existed in nesting locations in three sea turtle species sharing the same nesting beach. We measured accuracy and precision of hatchling orientation in hatchling loggerheads, green turtles, and leatherbacks, using tracks left in beach sand. Generalized linear models were used to investigate the effect of dune proximity on sea turtle hatchling orientation. A Kruskal-Wallace analysis of variance was employed to further understand differences in dune proximity of nests across species. The results indicated a significant decrease in hatchling orientation accuracy and precision across species as the distance between nests and dune increased, while green turtles and loggerheads showed similar orientation ability when in the same proximity to dune. We conclude that dune features are likely to provide important cues for hatchling orientation on sea turtle nesting beaches. Considering the importance of beach dunes to sea-finding success of hatchlings, we suggest management strategies to maintain natural beach profiles on sea turtle nesting beaches.