RIO DEL MAR – An Aptos man was playing with his dog at Hidden Beach Thursday afternoon when he noticed a 42-inch long shark wash up onto the beach.

The man and his dog had been playing for about 40 minutes, Tracy McAvoy said. Around 2 p.m. the dark gray and white shark washed up on its belly. From 50 yards away it looked like a dolphin because of the light gray color, he said. It only moved its mouth.

“I was happy to see him moving. I thought he might be dead,” McAvoy said. “It’s terrible to see any creature dead.”

When the waves washed ashore, McAvoy cautiously pulled the shark back into the water by the tail. The waves quickly washed the shark back up on shore, but McAvoy noticed the shark had become more responsive. on the second try, the shark managed to swim back out to sea and disappeared.

“It felt good; I think we may have saved him,” McAvoy said.

Sean Van Sommeran, shark researcher with the Pelagic Shark Research Foundation, said the organization’s Stranding and Collecting Unit has received multiple calls this week regarding salmon sharks washing ashore. Three were reported from Manresa, Carmel and Rio Del Mar.

Around 12:20 p.m. Thursday, the unit responded to a beached salmon shark that was in the surf line just south of Rio Del Mar beach. It had been in and out with the tide for at least an hour before they got the call, Van Sommeran said.

The shark was collected as a specimen and was taken to the marine lap at UC Santa Cruz. he said previous stranded specimens have showed signs of a bacterial infection in the nose that causes symptoms similar to demoic acid poisoning. a formal necropsy has yet to be scheduled.