An untagged female sea lion found critically injured near the Waipati Estuary, in the Catlins, last month, was euthanised due to the extent of her injuries.
And because the death closely followed the shooting deaths of a well-known mother and her pup in the area, conservationists called on the Department of Conservation (Doc) to expedite the necropsy of the third animal.
Some feared it could be the third human-inflicted death of a female sea lion in the remote Catlins in a matter of weeks.
A dead female sea lion, known as Jade, was found riddled with shotgun pellets in the Catlins Estuary in October after her young pup was shot and killed nearby.
Doc Murihiku operations manager John McCarroll said a necropsy had now been performed and found the sea lion was suffering from two puncture wounds in the left shoulder and chest.
The shoulder wound had broken the left humerus and left the sea lion unable to use its left flipper, Mr McCarroll said.
"It’s not known what caused these puncture wounds," he said.
"There is no suggestion the sea lion has been shot. The pathologist who carried out the necropsy could not rule out or confirm whether these were stab wounds."
The sea lion was a young female in fair health, he said.
"Losing any sea lion is a blow to the recovering Catlins population, but losing a young female is particularly tough as there are only about a dozen breeding age females in the region. Every one is extremely important to the future of the population."
Sea lions re-started breeding in the Catlins in 2006, he said.
And since, 45 pups had been born there, although a number of those had died over the years.
"While we don’t know if anything nefarious has happened to this sea lion, we ask people to look out for sea lions, especially over the holiday period when people will be enjoying the outdoors."
Mr McCarroll urged drivers in coastal areas of the Catlins and Otago to drive carefully because sea lions could be on the road and had been killed by cars in the past.
He also urged members of the public to contact the department if they saw anyone behaving suspiciously around sea lions.
Doc continued to investigate the shootings of Jade and her pup earlier this year, but there was no update at this stage, he said.
The New Zealand Sea Lion Trust is offering a reward of $11,740 for any evidence that leads to the conviction of those responsible for the shooting of female sea lion Jade and her 8-month-old pup.
