Nest site selection by the green turtle (Chelonia mydas) in a beach of the north of Veracruz, Mexico

Abstract

The distribution of the nests of marine turtles on beaches is one of the most important factors for hatchling success. Beaches with fine sands, moderate slopes and good humidity and drainage, are the main environmental variables for ovoposition. The objective of this investigation was to determine the nesting variations of the green turtle during which the nesting frequency per year, beach morphology and distance from the nests to the tidal line were registered. During the nesting seasons, 1 654 nests were registered on 13 beaches, among which significant differences in the number of nests per month were noted (f= 14.07; p< 0.05). Central beaches displayed major nesting probability and included beaches with short distances from the intertidal zone to the supralittoral zone. Dunes were the sites with greater preference for oviposition, being different from the sandy beaches and the intertidal zone (f=54.68; p< 0.05). Significant differences were found in the location of the nests with respect to the tidal line (t=2.33; p< 0.05), and the greatest intervals for nesting were between 10 and 24 m from the tidal line. The area displayed beaches with moderate slopes and dunes with an average distance of 22.6 m from the tidal line. This area is the most important nesting site for green turtle in the American Continent.