A SEVEN-YEAR-OLD boy and a captain who was recently praised as a hero are among eight people believed dead after a fishing boat sank in rough weather off the coast of southern New Zealand.

The sole known survivor from Thursday’s accident near Stewart Island was found clinging to a barrel in the ocean after enduring 18 hours in dark and cold conditions. He was taken to a local hospital suffering from severe hypothermia.

Rescue crews have recovered three bodies and hold out little hope of finding more survivors from the vessel Easy Rider due to poor sea conditions and a long delay before authorities were alerted to the accident.

The survivor, Dallas Reedy, 44, told police he was on the deck just after midnight when the boat was hit by a rogue wave, causing it to capsize almost immediately. He managed to cling to the overturned boat’s hull for about two hours before it sank, according to Invercargill Police Inspector Lane Todd.

The 40-foot boat was taking a family group to a remote island so they could hunt for mutton birds, which are considered a delicacy by some locals. There were three crew and six passengers on board, including the 7-year-old, Odin Karetai.

The captain of the boat, 47-year-old Rewai Karetai, was lauded two months ago when he helped rescue three people from another capsized fishing boat. Two people died in the earlier accident.

Police said the captain and the boy are related but are not father and son.

The Easy Rider sank at the southern end of New Zealand in Foveaux Strait, which is notorious for its treacherous conditions. According to New Zealand meteorological agency MetService, there were very rough seas in the area at the time of the accident as well as winds of about 65 kilometres per hour and heavy rain.

The MetService says the water temperature was about 13 degrees Celsius.

It took some 14 hours before authorities knew the boat was missing. The boat was supposed to meet with a helicopter Thursday afternoon, and when it didn’t show up, the helicopter pilot raised the alarm.

Police say that neither the survivor nor the three victims they’ve found were wearing life jackets. If the boat had an emergency locater beacon, police say, it wasn’t activated when the boat capsized.

Rescuers recovered the first victim Thursday evening and found two more bodies Friday afternoon, after a civilian ship assisted by the New Zealand navy located the wreck on the ocean floor, about 40 metres below the surface and 2 kilometres from the northwestern tip of Stewart Island.

Rescue crews are considering attempting a deep-sea dive onto the wreck Saturday, after equipment and specialised dive squads arrive.