BAHIA DE LOS ANGELES, Mexico - Its deep-blue waters surrounded by dusty desert peaks, the Gulf of California can appear tranquil and inviting. But often on a spring afternoon, powerful winds can howl out of the west and ferociously churn the sea.
Nine university researchers felt the fury of the gulf this week as they rode across a channel in an open boat about the size of an old station wagon. Led by a renowned scientist who had ridden these waters dozens of times, they set off for a quick trip back to their base camp for lunch.
But winds kicked up suddenly. Pounding waves soon filled their simple wood and fiberglass motorboat with water and the nine men and women were dumped into the sea.
Four men drowned, including expedition leader Gary Polis, whose body was recovered today, three days after the accident. The U.S. Coast Guard and Mexican navy continued to search for a Japanese researcher who was missing and feared dead.
While authorities continued to string together details of the tragedy, fishermen and other locals say they already know its cause: A boat with too many people aboard and boaters who were ill-equipped for the rough seas of Baja.
''Everyone says it's because they didn't have a guide,'' said Francisco Savin, 40, who has fished most of his life in the waters of Bahia de los Angeles, using a boat similar to the one that capsized.
The boat, known in Spanish as a ''panga,'' was owned by Polis, a top expert in scorpions who led the expedition from the University of California, Davis, and was well known in the tiny village of Bahia de los Angeles, some 300 miles south of San Diego.
The rugged islands around that part of the gulf are well known to researchers who frequent the area to study lizards, snakes, birds, marine life - and many species which exist nowhere else on Earth.
Polis, a California native who had traveled to the area regularly for more than a decade, would have been familiar with its sudden changes in wind and weather.
Following the accident midday Monday, Polis, a UC Davis researcher and two other Japanese professors were found dead.
U.S. and Mexican authorities said they didn't know whether it was Polis who was piloting the craft, and survivors left Bahia de los Angeles on Wednesday having said little about the incident.
All nine adults had either a life jacket or a seat cushion, according to Gary Huxel, 38, a post-doctoral researcher in ecology. Huxel and three other Davis students fought the rough seas for some five hours before reaching a pair of tiny islands and finding rescue.
Their boat was recovered later, moored a few yards off-shore and placed under the guard of Mexican soldiers.
Approximately 20 feet long, the boat would have been at or near its maximum capacity with nine adults on board - especially in heavy wind, several boating experts said.
''There should have been five or six people maximum,'' said Guillermo Galvan, whose family has rented boats and equipment in Bahia de los Angeles since 1949.
With the weight of nine adults, the panga would have been slower and had less maneuverability than normal. It also would have been closer to the water line, making it more vulnerable to waves, according to John Sieger, a power boat salesman and sportfishing captain in San Diego.
Those problems could have been overcome with a good guide, which normally costs around $30 a day in Baja, Savin said.
''A good guide would have known when not to go out because the wind is too strong and can steer the panga when you get into trouble,'' he said.
Mexican and U.S. authorities said Wednesday they were concentrating their efforts on searching for possible survivors - not on the cause of the accident.
One possibility was that some of the boat's occupants could have panicked and shifted their weight too suddenly, causing it to capsize, said Gordon Padgett, the general manager of a powerboat dealer in San Diego.
But searching for a cause was not an immediate priority for UC Davis, according to Bob Brewer, who was sent to represent the school as the search effort continued at Bahia de los Angeles.
''It was really a terrible experience,'' he said, ''and I hope we don't lose sight of the fact that what's important is the loss of fathers and the loss of husbands.''