At 3:50 p.m., a male surfer was paddling on his surfboard when what is suspected to be a bull shark bit him several times on his left arm, officials said.
The surfer said the shark's round nose came out of the water and the shark was 5 to 6 feet long, said Capt. Emily Hall, Martin County Ocean Rescue.
The man sustained nonlife-threatening injuries and had his wife take him to a hospital, she said.
"This is the time of year where we see more shark migration," Hall said. "It is not uncommon to see (sharks). After all it is their environment."
The shark bite comes after lifeguards twice Thursday had to call all swimmers and surfers out of the water after sharks were spotted in the area, Hall said.
Lifeguard had swimmers and surfers wait 20 to 30 minutes after the last shark had been seen to return to water.
About 2 p.m. officials received a report of a fisherman in an unguarded portion of the beach snagging a 5-foot-long spinner shark, said Daniel Harshburger, fire rescue spokesman.
However, the fisherman and other beachgoers returned the shark to the water, he said.
Fishing from the beach is not allowed in guarded areas of the beaches where people are swimming, because sharks are know for following schools of fish, Hall said.
Lifeguards flew double-red flags at the beach the remainder of the afternoon warning beachgoers of the presence of sharks, Hall said.