A woman suffered a significant leg wound in a late-night shark attack while wading in knee-deep water. 

Southland Police said a 21-year-old woman was walking through the water in an estuary near the Riverton rugby grounds about 2am on Monday when the attack happened. 

“She received a significant laceration to her leg that required treatment from emergency services,” a police spokesperson said. 

“The culprit is possibly a sevengill shark, which is present in the estuary. The time of day is a possible factor.” 

Hato Hone St John confirmed they were notified at 2.27am on Monday “of an incident involving an animal”. 

“We responded [with] one ambulance and one rapid response unit to Leader St, Riverton,” a spokesman said. 

“Our paramedics treated and transported one patient in a serious condition to Southland Hospital.” 

Located 30km west of Invercargill, Riverton is a popular holiday destination and police are asking anyone heading into the water to “follow safety guidelines and avoid late-night swims”. 

Speaking to the Herald in 2022, New Zealand Marine Studies Centre educator Rob Lewis said that in southern New Zealand, sevengill sharks often moved closer to shore in the summer. 

They were “very curious animals” and fast movements and splashing could trigger them to investigate. 

“Of course, their way of investigating is by biting things,” Lewis said. 

If approached by a sevengill shark, the most important thing to do was to keep eye contact with it, he said. 

“After which, you should try, as calmly as possible, to exit the water.” 

Water Safety NZ has resources and advice for all water-going holidaymakers.