Hell hath no fury like a reformed dolphin trainer. Anyone who has dealt with Russ Rector knows that all too well. From 1968 to 1975 he worked and performed with the creatures at Fort Lauderdale's Ocean World. Today he is president of the Dolphin Freedom Foundation, which he founded in 1992 as a platform from which he could launch relentless attacks against those who do what he once did: hold dolphins captive, or otherwise endanger them. In 1990 he clung to a buoy off the Dry Tortugas to disrupt a U.S. Navy test of underwater explosives he believed could harm the area's wild dolphins. In 1993 he and other activists made a very public stink when Aruba proposed to build a tourist swim-with-the-dolphins facility. In 1994 he was arrested for trespassing at North Key Largo's private Ocean Reef Club, where he was denied access to check on the welfare of three captive dolphins held by the club. In July 1995 he set his sights on the aging Miami Seaquarium, which keeps dolphins and a killer whale named Lolita. Acting on a tip from employees, he videotaped what appeared to be serious structural problems with the main performing stadium. His protests to county, state, and federal agencies went nowhere. For several years in the mid-Nineties he noisily argued that Lolita's holding tank was too small, again to no avail. But last year the 55-year-old sea-mammal advocate connected. Brandishing another videotape and a safety expert's report, commissioned by his foundation, Rector documented scores of electrical code violations at the Seaquarium. This time Miami-Dade County officials responded, slapping the attraction with nearly 140 violations. Cost for repairs: roughly a half-million dollars. Last month he was at it again. A new report by the safety expert alleged more violations, including inadequate emergency exits for Seaquarium visitors. Is he obsessed? Yes. Is he overbearing? Yes. Is he a hero? Certainly not to Arthur Hertz, CEO of Coral Gables-based Wometco, which owns and operates the Seaquarium. But to many other people, here and elsewhere, the answer is yes. He's a hero.