Photo copyright Luis Lamar.

Famed underwater photographer Wesley Skiles, a pioneering cave-diver, explorer and conservationist, died Wednesday while on assignment for National Geographic. He was 52.

Skiles was involved in a diving accident off the coast of eastern Florida, the details of which are still under investigation. Underwater at the time, he signaled to other divers that he was ascending to get more film for his camera. However he never returned to the surface. Colleagues found him on the ocean floor and rushed him to St. Mary’s Medical Center in West Palm Beach. He was pronounced dead shortly after.

Known as a pioneer in underwater photography and film making, Skiles was renowned for his enthusiasm and daring in seeking out remote underwater caverns where no one had ever filmed before. He produced over 100 films for television, and was noted for his passion for conservation education. Skiles’ amazing photo of the blue caves in the Bahamas Islands is on the cover of the current issue of National Geographic.

“Wes was a true explorer in every sense and a wonderful spirit,” said Chris Johns, National Geographic’s editor in chief. “He set a standard for underwater photography, cinematography and exploration that is unsurpassed. It was an honor to work with him, and he will be deeply missed.”