Mapping the path of the biggest fish: The whale shark from the Mexican Pacific side

Whale sharks exhibit distinct size-based segregation and high site fidelity in their movements, with juvenile aggregations predominantly occurring in coastal waters (Los Angeles Bay, La Paz Bay, San Luis Gonzaga, Nayarit, and Coyote Bay), while pregnant adult females congregate in oceanic regions like Espiritu Santo Island, Los Cabos, and the Revillagigedo Archipelago. A 21-year photo-identification study identified 898 sharks, revealing that juveniles (841 individuals) show remarkable fidelity to coastal sites, with up to 61% re-sighted annually in La Paz Bay, while adult females exhibit lower recapture rates. The research highlights the need for regional conservation strategies, as only three of eight studied localities are currently protected.

Ramírez-Macías, D., Vázquez-Haikini, A., Luja, V., Murillo, R., & Mata, R. (2016). Mapping the path of the biggest fish: The whale shark from the Mexican Pacific side. The 4th International Whale Shark Conference. https://doi.org/10.5339/qproc.2016.iwsc4.46