The roughly 700-pound common dolphin was seen swimming in circles in shallow water. Fish and Game officials said while the dolphin appeared disoriented, it seemed healthy.
"He's not used to being in a confined area," said Dean Gomersall of the Pacific Marine Mammal Center.
At least six other dolphins were seen swimming in Huntington Harbour, just west of Warner Avenue. Officials believe the dolphins have been in the harbor area since Wednesday feeding on fish, but the wayward dolphin strayed away from its family, swimming underneath a bridge at Warner Avenue.
Rescue crews got in the water and observed the dolphin, but they decided not to attempt a rescue.
"Sometimes when rescuers intervene when they shouldn't, if we intervene prematurely, we can complicate the issue, and it can backfire on us," said Peter Wallerstein of the Los Angeles County Marine Animal Rescue. "We are going to kind of back off, let the tide come up. Nine times out of 10, these animals will find their way out. They're very smart animals."
Dozens of spectators pulled off Pacific Coast Highway to get a look at the dolphin.
"People always find it curious ... I was surprised, caught my attention. I had to come over and see what was going on," said Guy Conigliaro of Long Beach.
Fish and Game officials say the dolphin has plenty of food to eat in the wetlands. They are hoping the mammal finds its way out in the next day or so.
Because of poor lighting, officials were unsure if the dolphin was still in the area Friday night. Experts were expected to be back at the shore at first light Saturday to see if there are still signs of the dolphin. If so, they may need to use more drastic measures to get it back toward Huntington Harbor.