BOLINAS -- Authorities in Marin County on Monday resumed their search for.
The Coast Guard said they received a report at 10:40 a.m. of a person swimming who was attacked by a shark and pulled under at Wildcat Beach at the southern end of Point Reyes.
Marin County firefighters responded and determined that three men who had gone for a swim encountered a shark which attacked one of them. The others swam back to shore and told first responders there was a large pool of blood in the water.
The men said that, before the attack, they had been swimming about 25 to 50 yards from the beach. Authorities still have not confirmed that a shark attack occurws.
Authorities said the missing swimmer is approximately 50 years old. The three swimmers were camping with a group of about 10 to 15 people above the beach in an area called Wildcat Campground.
"The further amount of time, it decreases the chance of survivability," Batt. Chief Todd Overshiner with the Marin County Fire Department said Sunday.
On Monday, National Park Service (NPS) officials from Point Reyes National Seashore said they were working with other agencies to continue their search for the missing swimmer
While the U.S. Coast Guard suspended its search in the frigid waters Monday morning with no results, a ground search continues with first responders from the NPS, the Marin County Sheriff's Office and the Marin County Fire Department, and the Stinson Beach Fire Department.
Authorities said the search was initially conducted by land, water and air. At least one agency is now calling this, a recovery effort.
First responders scoured the coast on watercraft near Wildcat Beach for the second straight day, but more than 24 hours after a swimmer was reported missing, there were no visible signs of life.
"We do remain hopeful for positive outcome, and at this point, we will continue our search efforts through the day," said Point Reyes National Seashore Public Information Officer Christine Beekman.
Most of the operation is being conducted from a bluff overlooking the area where the 52 year old man was last seen.
"They're using binoculars and spotting scopes to be looking for any any sign of the missing individual," explained Beekman.
Dave Ebert is the director of San Jose State's Pacific Shark Research Center. He says there are more great white shark sightings in the area in September and October because of elephant seals and sea lions giving birth.
"It's pretty unusual here where there's an incident when a swimmer is attacked and just completely disappears," said Ebert. "From predator standpoint it's a good hunting time. You have young, inexperienced elephant seals and sea lions going in the water,"
But Ebert emphasized that in the 70 plus years of tracking shark attacks in California, the average has remained very consistent with only three to four incidents a year.
"They tend to hunt where they have an advantage," he said. "If you think about the surf, you know, the sea lions can't always pick up on stuff because of all the activity. And that's where whites will often attack."
Ebert says Marin County has among the higher number of shark attacks compared to other counties across the state since 1950.
The identity of the missing swimmer is being withheld pending notification of family and in collaboration with law enforcement agencies.
Kenny Choi contributed to this story.
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