Police have spoken to a boat owner after he was reported to have harassed a dolphin in waters in Cornwall.
The code of conduct exists to protect marine wildlife
A member of the public called police a after the alleged incident at Sennen Cove.
When the boat owner returned to the shore he was informed about the Marine Creatures Code of Conduct, which exists to protect marine wildlife.
The code states that boats should stay at least 100m (328ft) away from dolphins.
It also says if the creatures approach a boat, the engines should be switched to neutral.
The code also tells boat owners to totally avoid groups with mothers and young.
Joana Doyle, marine conservation officer for Cornwall Wildlife Trust said: "We are lucky enough to get 17 species of whales, dolphins and porpoises as well as basking sharks and turtles visiting the South West.
"The last thing we want to do is to drive these beautiful animals away from our coast and their feeding grounds."