Crews attempting to aid a blue whale that became entangled in what appeared to be heavy fishing line off Point Fermin in San Pedro worked into the night Friday to try to free the giant mammal, but eventually lost track of it, officials said.
"They were going to come in but decided to go back out and try to cut off as much line as they can," said Justin Viezbicke, California Stranding Network coordinator for the National Oceanic and Atmospheric Administration.
Crews had earlier attached buoys to the line to dissuade the whale from diving and to better track the animal.
But Viezbicke said that the marine mammal experts on the scene determined that the best course was to remove as much of the line as possible to reduce the drag and fatigue on the whale.
Late Friday night, Viezbicke said crews had gone back out but were unable to find the whale and would resume their rescue effort on Saturday.
The mammal appears to be trapped about eight miles from Point Fermin, between San Pedro and Catalina Island, officials said. The whale was reportedly trailing at least 200 feet of line, possibly with a crab pot on the end of it.
Dan Salas, a captain with Harbor Breeze Cruises, said one of the company's boats spotted the animal during an afternoon whale-watching trip.
"Nothing was unusual until the captain got close and he immediately noticed that the whale was in distress," Salas said. The whale is reported to be about 75 feet long. The captain saw about 400 feet of line attached to the whale's tail, and a buoy hanging off the end, Salas said.
The largest animals on Earth, blue whales can grow to more than 100 feet long and weigh 150 tons. About a quarter of the estimated worldwide population of 10,000 congregate in the waters off the West Coast.
A record number of West Coast whales became entangled in crabbing gear in 2014, according to a report released earlier this year. At least 30 whales -- most of them grays and humpbacks -- were entangled in vertical lines between surface buoys and crab traps on the ocean floor last year, nearly twice as many as reported the year before, according to the NOAA's National Marine Fisheries Service.
Experts expect 2015 to be another record-breaker: as of April, 25 entangled whales had already been reported off the coast of California.
"You've got a horrible situation because you've got these innocent fishermen who are just really trying to do their job, and then you've got these innocent whales, and they just happen to overlap," said Diane Alps, programs coordinator for the Cabrillo Marine Aquarium.