Fay died of a heart attack at Berkley West Convalescent Hospital in Santa Monica on Tuesday after a series of strokes that had left him incapacitated in recent years.
A UCLA-trained biochemist and professional diver who collected specimens for biomedical research, Fay focused public attention on industrial discharges of the pesticide DDT off the Palos Verdes peninsula that made fish too toxic to eat and nearly drove the California brown pelican to extinction. He was among the first to call for Los Angeles to halt dumping of sewage sludge, a once-quixotic quest that drew kindred souls in the 1980s who joined with him to launch the movement to clean up coastal waters.
He spent six years as a state coastal commissioner, until complaints to Sacramento leaders about his uncompromising anti-growth attitude and open outrage about damaging coastal wetlands and beachfront got him fired. He was replaced on the panel by a developer.
Admirers often likened Fay to John Steinbeck's friend and drinking companion, Edward F. Ricketts, a pioneer of marine ecology who inspired the character "Doc" in the novel "Cannery Row."
"He was so much like Doc Ricketts," said Dorothy Green, who joined with Fay and others to launch the nonprofit group Heal the Bay. "He earned his living collecting animals for research. He drank too much. He would go out diving at night -- alone."
Fay supplied sea creatures, aquarium tanks and advice during the production of the 1982 movie of "Cannery Row," starring Nick Nolte and Debra Winger. His son, Douglas, has a vivid recollection of his beaming father on the movie set: "He was puffing on his cigars. That was one of the best times."
Fay also spent much of his life, after his divorce in 1975, living and sleeping in his laboratory, located first in Venice, then in Inglewood and Port Hueneme.
Far more comfortable in a wetsuit than a dress shirt and jacket, Fay logged thousands of hours prowling the seafloor doing his own research and collecting specimens.
"He has probably spent more time underwater than any man on the planet," said Harold Dunnigan, a former Navy diver and retired Los Angeles County lifeguard who taught Fay how to dive in 1955. Dunnigan said he could easily out-compete Fay in swimming contests, but underwater, few could keep up with him. "He was at one with the ocean."
Over a span of 40 years, Fay made four to six dives a day, mostly collecting live sea animals for his business, Pacific Bio-Marine Labs. He would whisk the animals to meet planes departing nearby Los Angeles International Airport to biomedical researchers at universities worldwide.
His live specimens were used to study human nerve cell damage as well as to develop weapons against tumors and to concoct a non-addictive pain reliever.
Fay supplied sea hares, Aplysia californica, to Columbia University neuroscientist Eric Kandel, who shared the 2000 Nobel Prize for research on the physiological basis of memory storage in neurons, said Janet Fay, his ex-wife, who lives in Salinas, Calif.
Fay celebrated the contributions his marine creatures made to mankind, but often lamented the disservice that man had done in return to sea life and undersea habitat.
"They've dumped everything in this bay except radioactive waste," he once complained to a Times reporter.
Although he saw some improvement in recent years, Fay was disappointed at the long-term trends that had transformed Southern California waters from a major fishing area into an industrial dump.
He talked about the burden of knowing how the bay looked more than 40 years ago, and how it appears today.
"You spent your whole life around the ocean, you develop a sense of responsibility to the environment. If you don't respond to your convictions, then what kind of person are you?"
Born July 22, 1929, in Santa Monica and raised in Venice, Fay remembered his father, a recreational fisherman, reeling up barn-door-sized halibut from the bay at a time when boys wading into the surf at Venice Beach could still see both their feet and darting fish.