The San Francisco Police Department has sent a negotiator to talk down a man who is standing on a railing on the westbound side of the Bay Bridge near Treasure Island, according to California Highway Patrol Officer Virgil Aquilar.Also assisting in the situation is the U.S. Coast Guard, which has sent two boats to the Bay Bridge "for any type of rescue and assistance should the man decide not to go back over the rail onto the auto deck,'' Coast Guard Petty Officer Gabriel Flesher said.