Dr. McCosker was a Senior Scientist and the first Chair of Aquatic Research at the California Academy of Sciences.
He retired in 2014 and continues to occupy the chair in an emeritus capacity.
From 1973 through 1994, he was Director of the Steinhart Aquarium in San Francisco. He received his PhD in Marine Biology from the Scripps Institution of Oceanography.
His research activities have taken him around the world underwater, and include field and laboratory studies ranging from microscopic bioluminescent bacteria to macroscopic man-eating elasmobranchs (sharks and their relatives).
He has also studied the taxonomy of snake eels and moray eels, the marine life of the Galápagos, the biology of salmonid fishes, dispersed and renewable energy sources as alternatives to national vulnerability and war, and the public understanding of sustainable seafoods.
His conservation activities have involved the banning of trade in shark fins in California and the protection of endangered salmon.
His studies of white sharks have resulted in the publication of more than 260 technical and popular publications, books, and documentaries that have changed our understanding of white shark behavior and helped to formulate public safety policies and legislation to protect the species. During his tenure as Director of Steinhart Aquarium, it became the first aquarium to display a live white shark in captivity — that survived. After nearly a week of swimming in the former Fish Roundabout, Sandy was released back into the Pacific Ocean off the Farallon Islands in August 1980 — a landmark moment in McCosker‘s career and a sea change in the Aquarium industry.