Hundreds of dead sharks have washed up on the Iranian Shif island.
The sharks are thought to have been killed for their fins as fishermen catch the sharks for their fins before throwing the dead sharks back into the sea, leaving them to wash up on the shore.
The fins are believed to have medicinal properties, officials say, however catching the sharks is illegal.
The fine for catching a shark is about $7,000.
According to the BBC after cutting off the fins, they throw the dead sharks in the sea because they fear they will be fined.
The sharks end up washing up on the beach, an environment official in the southern port city of Bushehr is quoted as saying by IRNA news agency.
The price for 1kg (2.2lb) of shark fin is about $2 (£1.50), the director-general of the Environmental Protection Organisation, Hoseyn Delshab, said.
Shark fishing was banned in Iran in 2014 over concerns the population was facing extinction.