t precisely 7 a.m., 15 miles off the coast of Portland, Maine, the computerized brain of Buoy E snaps to life. It's a raw and rainy day out on the ocean, where gray skies blend into gray waves beneath a veil of rain. There's little to mark the passage of space or time, save for foraging seabirds, the occasional gust of wind, and E's 10-foot-tall, fluorescent-yellow body rising and falling on the swells. As it does every hour, the aluminum buoy -- outfitted with sensors, solar panels, and antennae -- opens a cell phone connection and dials up its home office 100 miles away at the University of Maine campus in Orono. Data fly through the ether on microwaves: The buoy relays the pattern and frequency of the three-foot swells, while its infrared eye takes a reading of atmospheric visibility (low today, owing to the rain). Seven instrument clusters attached to its thick mooring cable measure the temperature, salt content, and current flows from the ocean surface to the seafloor some 300 feet below. Atop Buoy E's mast, wind vanes and a spinning propeller report changes in the wind's speed and direction over the past hour.

At the other end of the phone connection, computers at the University of Maine's School for Marine Sciences also take calls from Buoy E's nine sister buoys scattered across the Gulf of Maine, a 450-by-200-mile semi-enclosed sea stretching from Cape Cod to the head of the Bay of Fundy in Canada. A rich stream of spectrographic images, collected by four ocean-observing radars, pours into the computers' hard drives. The radars -- whiplike antenna systems erected in front of lighthouses -- detect changes in surface currents and wave patterns from one end of the gulf to the other. Out in space, three satellites operated by the National Oceanic and Atmospheric Administration and NASA beam down full-color images showing not only surface temperatures across New England's sea, but even concentrations of phytoplankton, the tiny marine plants on which fish life depends. All this information is digested and wired down to a Portland office tower, where the staff of the Gulf of Maine Ocean Observing System (GoMOOS) place it on their online servers.

The federal government spends more than $3 million a year to observe the Gulf of Maine, whose prolific fishing banks saved the Pilgrims from starvation, fueled the expansion of colonial New England, and until recently supported an immense fishing industry. Launched in 2001, GoMOOS gathers data on ocean conditions here and releases it to the public free-of-charge -- much as the National Weather Service does for our atmosphere. GoMOOS, a Portland-based consortium of research institutions, nonprofits, commercial associations, and state and federal agencies in New England, Maritime Canada, and Washington, is one of the most sophisticated ocean observing systems on the continent. It also happens to be the prototype for a national network of ocean observing systems that could transform the way we manage our seas.

For the first time, marine scientists can tap into a vast database of oceanographic information that is gathered every hour, 24 hours a day. By combining GoMOOS's temperature and current maps with, for example, new, highly detailed maps of the ocean floor, biologists may be able to figure out how lobster larvae travel on ocean currents (some think they come from as far away as Nova Scotia.) Oceanographers trying to understand the life cycles of cold-water corals in the gulf's deepest canyons are using the new technologies to help pinpoint where to submerge their deepwater submarines. And by logging onto the GoMOOS website (www.gomoos.org), a herring fisherman can use the system to locate phytoplankton blooms and promising temperature fronts -- thus making the tricky task of finding the the fickle schools of silvery fish far easier. Most important, by providing scientists and fishermen clues about the region's entire marine ecosystem, the new technologies may help them bring the Gulf of Maine and its ailing fishing industry back from the brink.

"You're not going to have any fish to catch -- or healthy fishing communities -- unless there is a healthy marine ecosystem to provide those fish," says Jane Lubchenco, a professor of marine biology at Oregon State University in Corvallis. "We need mechanisms to better understand how ocean ecosystems work if we are going to do a better job of managing them."

It is indeed sadly appropriate that ocean observing is being tested here in New England, whose storied fishing grounds have been largely closed due to lack of fish. From 1980 to 2001, for example, New England's haddock catch fell by 77 percent, Atlantic halibut by 87 percent, and cod by 71 percent. Some stocks will take years to recover, others decades, and a few, like the shoals of 600-pound halibut, will probably never return. In the early 1990s, fishermen turned to creatures once derided as "trash fish" -- dogfish, silver hake, even sea urchins and baby eels -- only to see their numbers crash as well.