• sea turtles;
  • Caretta caretta;
  • nesting beach selection;
  • multiple regression analysis;
  • Okinawa Islands


Based on data obtained from 3 years' fieldwork in Okinawajima and adjacent islands of the central Ryukyus, Japan, various physical and human-related beach characters were assessed for their relative influence on beach selection by nesting sea turtles using multiple regression analysis. Of the 23 characters considered, sand softness (measured by a specially designed tool) (positive), distance from the nearest human settlement (positive), presence of lagoon (positive), beach length (negative), and beach height (positive) were selected as influential variables in descending order. Explanations were attempted for such results in the light of correlates of these beach characters with natural and artificial factors that are believed to impact the nesting success of female sea turtles.