Police in New Zealand are investigating reports that Moko the solitary dolphin who has a reputation for stealing surfboards and balls from swimmers was attacked with a paddle after annoying a canoeist.

Moko has spent the past three years on the North Islands' east coast travelling between Mahia and Gisborne. He has taken to overturning kayaks, tipping over water skiers and interfering with surf lifeguard training. When he recently prevented a female canoeist going back to shore, she lost patience with Moko and hit him with an oar. The dolphin hasn’t suffered any injuries however after the incident a witness said he was skittish and reluctant to approach people for a while.

Police are investigating the alleged assault on him. New Zealand law protects sea mammals such as Moko from harassment, with offenders facing fines of up to 30,000 New Zealand dollars (US$22,200) under the Marine Animals Protection Act.