Magnetic features of marine black turtle natal beaches and implications for nest selection

Abstract

The beaches of Colola and Maruata, Michoacán, southern México are nesting places of the marine black turtle, Chelonia agassizi. Marine turtles use magnetic cues to orient their long distance navigation, and might also use magnetic such to refine their geographical position within their natal area. We present results on the characterization of nesting beaches in terms of magnetic properties. Hysteresis parameters may allow distinguishing nesting from non–nesting beaches. The results may have implications for the selection and identification of nesting sites by marine black turtles, in the context of magnetic orientation mechanisms.