Revillagigedo Archipelago

Overall, our team of scientists found an interesting mix of tropical and temperate species. They observed a high diversity of sharks, consisting of at least eight species, and a high fish biomass with several endemic species. The abundance of mantas was exceptional. Large predatory pelagic species were also abundant, with sharks and tuna observed regularly. Five species of shark from two families were observed; the most common was the silky shark, occurring at 92% of all locations. Yellowfin tuna were abundant in the waters sampled, appearing in 28% of drops, sometimes in large schools. Olive grouper (Epinephelus cifuentes), and sharks and chimaeras were common. Of these cartilaginous fishes, the purple Chimaera (Hydrolagus purpurescens) was the most abundant and occurred on 40% of the surveys. Tiger shark, Galeocerdo cuvier, was observed at 1,229 m. Prickly shark (Echinorhinus cookie) and Combtooth dogfish (Centroscyllium nigrim) at 1,807 m and 1,134 m, respectively. The team documented new records of elasmobranch species in the Archipelago. With the Dropcams, they found the sleeper shark (Somniosus microcephalus), prickly Echinorhinus cookei and longnose skate (Raja spp). These are the topline principal findings, as the comprehensive scientific results of the expedition are still being determined.