Habitat suitability and environmental factors affecting whale shark (Rhincodon typus) aggregations in the Mexican Caribbean

The Mexican Caribbean is considered one of the most important sites for whale shark aggregations. Whale shark groups of over 300 individuals have been recorded frequently. There is little published information regarding the ecology of the whale shark in Mexico, and the role that the Mexican Caribbean plays as habitat for this species. This area has been recognized as important for the whale shark and therefore it is necessary to determine the environmental factors that shape the distribution of these animals. The aim of this study was to identify key environmental factors associated with whale shark feeding aggregations and to determine the patterns in habitat suitability for whale sharks in the Mexican Caribbean through the modeling approach of maximum entropy. Whale shark data obtained for this study included 250 records during April to September (2008–2012). The MaxEnt model performed better than random and produced an area under the curve (AUC) score of 0.946. Primary productivity and sea surface temperature were the variables most strongly related to whale shark sightings. The model predicted a high suitability in areas located to the north of Isla Contoy and the offshore area east of Isla Contoy named “Afuera” (>0.75), with medium suitability north of Cabo Catoche (>0.5) and lower suitability for the northeast of Cabo Catoche (<0.5). The habitat suitability maps also indicated seasonal variations, showing a higher prediction of whale shark sightings during the rainy season (June to October), when primary productivity is higher in the area.