The distribution of the nests of marine turtles on beaches is one of the most important factors for hatchlingsuccess. Beaches with fine sands, moderate slopes and good humidity and drainage, are the main environmentalvariables for ovoposition. The objective of this investigation was to determine the nesting variations of the green turtleduring which the nesting frequency per year, beach morphology and distance from the nests to the tidal line wereregistered. During the nesting seasons, 1 654 nests were registered on 13 beaches, among which significant differencesin the number of nests per month were noted (f= 14.07; p< 0.05). Central beaches displayed major nesting probabilityand included beaches with short distances from the intertidal zone to the supralittoral zone. Dunes were the sites withgreater 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 thegreatest intervals for nesting were between 10 and 24 m from the tidal line. The area displayed beaches with moderateslopes and dunes with an average distance of 22.6 m from the tidal line. This area is the most important nesting sitefor green turtle in the American Continent.

Recent studies have shown that acoustic signals play an important role in turtle social behavior and reproduction. We recorded embryos and hatchlings of Lepidochelys kempii inside the nest...

Anthropogenic habitat disturbances are causing large-scale declines in animal abundance. For many species, information on the drivers of decline is lacking or restricted to single sites, despite calls for regional approaches. In this study, we determined the effect of different types of habitat disturbance (natural or anthropogenic) and ecological factors on Geoffroy’s spider monkey (Ateles geoffroyi) abundance using a regional approach. We selected this study species because of its high degree of social flexibility and its endangered status. We surveyed 4 sites in the Yucatan Peninsula and recorded the number of individual monkeys encountered along 72 line-transect segments each measuring 500 m. Habitat disturbance variables were obtained from open-access databases and included distance to roads, presence and number of hurricanes, forest loss, and presence of forest fires. Ecological factors were based on data collected during vegetation surveys and included number and basal area of feeding tree species, and canopy height. We ran generalized linear mixed models and found that monkey abundance was negatively affected by forest loss but positively affected by the basal area of feeding trees. We, therefore, suggest that a combination of anthropogenic and ecological factors affects spider monkey abundance. Spider monkey’s high degree of social flexibility may be a mechanism allowing them to adjust to changes in their environment when canopy connectivity is not lost. Our results provide policy and conservation decision makers with key information to develop regional conservation plans. Additionally, our methods can be used to identify the factors that affect the abundance of other mammal species.