Editors: This 11:45 a.m. update on Thursday, March 30, adds information about the recovery of Gary Polis' body and adds information about the return of the expedition members. Editors: Photographs of the dead and missing individuals are available through the Associated Press. According to a University of California, Davis, faculty member in Bahia de Los Angeles, searchers this morning recovered the body of UC Davis ecology professor Gary Polis. The U.S. Coast Guard and Mexican Navy will continue searching for Shigeru Nakano, 37, a Kyoto University researcher, who is the only missing member of Monday's boating accident in the Sea of Cortez. Researchers, participants and survivors of the accident are expected to return to Sacramento late today. The group will be crossing the Mexico border about midday, and then will be required to meet with U.S. Coast Guard investigators for a debriefing before it is free to return home. UC Davis has chartered a private jet to transport the group, as well as some family members, to Sacramento International Airport today. UC Davis officials, including Chancellor Larry N. Vanderhoef, Agricultural and Environmental Sciences Dean Neal Van Alfen, and campus counselors, are en route to San Diego to accompany the group home. It is not known yet when the group will arrive in Sacramento, as it is dependent on the length of the meeting with U.S. officials in San Diego County. Four people have now been identified as having died in the accident, which involved a research expedition led by Polis. In addition to Polis, Michael D. Rose, a UC Davis postgraduate researcher, and two Kyoto University ecology professors have been confirmed as dead. Confirmed as rescued are these individuals from UC Davis: postgraduate researcher Gary Huxel, undergraduate student Sarah Ratay, graduate student Becca Lewison and graduate student Ralph Haygood. Lewison, 28, of New Jersey, is a Ph.D. candidate in ecology. Ratay, of Corning, 20, is majoring in genetics. Haygood of Fresno, 35, is a Ph.D. candidate in population biology. UC Davis Chancellor Larry N. Vanderhoef said the accident was "the most tragic in the history of the university" and "our hearts go out to all of the families." The researchers were part of an expedition of about 20 people visiting the Sea of Cortez to study the ecology of spiders and scorpions that inhabit the area's islands. Grief counselors are assisting friends and colleagues on campus. A delegation of Japanese representatives from Kyoto University and family members was traveling on Wednesday to the United States. The accident occurred between noon and 2 p.m. Monday. An undetermined number of the research group left the town of Pueblo de Bahia de Los Angeles, about 300 nautical miles south of San Diego, Calif., on Monday morning in two boats to conduct research on Isla de Cabeza de Caballo, located about 4 nautical miles off shore. Both boats headed back to port mid-day, but became separated when the wind whipped up four- to six-foot waves. When the crew of one boat arrived at port and realized the other vessel had not yet arrived, it returned to search for that boat. The boat was reported missing to officials in Mexico at 10:30 p.m. Monday night. Several survivors were discovered on the Isla de Los Gemelos. They reported that their boat had begun to take on water and flipped over. Some of the group swam for land, while others stayed with the capsized boat, survivors said. Witnesses and survivors said everyone in the capsized boat had been wearing a life jacket. Early reports described the boats as 22-foot, inflatable boats, but that appears to have been incorrect. The capsized boat is now understood to have been a 22- to 30-foot, Boston-Whaler type of vessel. A description of the boat that returned to port safely is not yet available. Because the incident occurred in Mexico's territorial waters, the search effort is being led by the Mexican Navy using a helicopter, fixed-wing aircraft and high-speed boat. The offices of U.S. Sen. Dianne Feinstein and Congressman Doug Ose have been working with the U.S. Embassy in Mexico City to assist in the search efforts, and to assure the safe return of all those who took part in the expedition. The News Service will update this advisory as more news becomes available.