It's hard to put a finger on what drives the wild popularity of Deadliest Catch, the Discovery Channel's series about crab fishing in the Bering Sea. Pulling load after load of crustaceans off the bottom of the ocean seems like pretty thin stuff for a runaway entertainment phenomenon. Yet the show has somehow won over more than 4 million viewers and garnered five seasons of red-hot ratings.

Granted, the weekly drama of the Red Bull-guzzling, cigarette-huffing, bleepity-bleeping captains doing battle with 13 million pounds of king crab does give the show a certain NASCAR-worthy je ne sais quoi. But if there's a single secret ingredient behind the show's success, it is the drama of the multimillion-dollar fishing derby -- starring the likes of Phil Harris, spitting blood and tearing his hair out as his boat gradually falls apart around him, and Johnathan Hillstrand, like a Hells Angel behind the wheel of the Time Bandit -- to catch as many crabs as possible before the government drops the checkered flag on the season. Though it's not much discussed on the show, the scramble for crab is just a videogenic symptom of a larger -- and potentially catastrophic -- problem in fishing: Too many boats chasing too few fish.

"You could've had 25 boats easily catching the whole quota," says Edward Poulsen, a second-generation Bering Sea crab fisherman. "But there were 300 boats."

That free-for-all brought a host of problems, from environmental damage caused by carpet-bombing the ocean floor with crab pots, to bankruptcies and a chilling roster of lost fishermen and boats that sank after they ventured out into fierce storms so they wouldn't get left behind in the race. For years, crab fishing in the Bering Sea was the deadliest job in the country -- more likely to kill you than going on foot patrol in Iraq.

But even as the Deadliest Catch rocketed to popularity, the hard lessons of two decades of racing for fish were finally sinking in for fishermen in the Bering Sea, and they were voluntarily agreeing to end the race. You'd never know it from watching the show, but only one season after it hit TV screens, crab fishermen in Alaska began fishing under a new system that permanently divided up the annual catch between all the boats in the fishery. 

"The whole dynamic of the fishery has changed," says Kale Garcia, another longtime crab fisherman, who owns a boat called the Aquila.

In the Bering Sea today, the race for crab is now over. But the fishery there is just one ripple in the tide of a revolution that has swept the fishing world over the past 20 years. Today, fisheries for everything from fish-stick staples like whiting and pollock to high-end delicacies like halibut and sablefish operate under "catch share" programs. Many more, including a major groundfish fishery on the West Coast and one in New England, are now following suit. Jane Lubchenco, the marine biologist who now heads the National Oceanic and Atmospheric Administration (which manages the nation's fisheries) has launched a concerted effort to institute catch-share programs in as many U.S. fisheries as possible.

Yet even as the tide rises for catch shares, the fleet and the crews in the Bering Sea are still contending with far-reaching aftereffects -- something not seen on TV, and not much discussed by catch-share boosters.