Hero photograph
Kotahi the NZ Sea Lion and her pup Rocky.
 
Photo by Supplied to NZ Sea Lion Trust

Kotahi the Sea Lion

John Burke, NZ Sea Lion Trust —

Sea Lions are beautiful creatures. Their return to the shores of New Zealand has been one of the greatest self reintroduction stories of an endemic species in the world. In 1993 'Mum' was the first female NZ Sea Lion to give birth on the mainland for a hundred years. She went on to have 11 pups and established a small breeding population. But this is the story of another female known as Kotahi and the unusual place where she chose to give birth.

As female sea lions increased in number a Trust was set up in 2003 by Shaun McConkey and Brian Templeton to help document their return and monitor their progress around the New Zealand coast. In those days there were fewer than 10 female sea lions on the mainland and they were all daughters of the matriarch 'Mum'.

One thing that remained constant was that sea lions preferred sandy beaches as haul outs while their cousins, the New Zealand fur seals would opt for rocky outcrops.

Until we met Kotahi.

Kotahi was an unusual mother who was discovered by the family of the local landowner close to Akatore in January 2017. While visiting a beach in the area they went to show some visitors the fur seal colony that was located on a rocky shoreline. Many fur seal mothers and their pups were known to use the area as it provided a safe environment for the seals to play and grow while the mothers would be feeding at sea. But on this day there was a surprise. In amongst the fur seal colony was a large pregnant sea lion who had crossed over the rocks through the colony and was sharing a rock with a large fur seal.

They were amazed and contacted DOC and the Sea Lion Trust.

Following a site visit the sighting was confirmed and not only that, a newborn pup was discovered too. He (for it was a boy) became known as 'Rocky' as he was the only pup that we knew of who had been born next to a fur seal colony. Rocky was tagged, receiving the number 9050. We believed that he was going to be a one off but in the last two years Kotahi has returned to the same spot and had two more pups, Rocky's younger brother Wero who was born in 2018 and another, as yet to be named boy, born in 2019.

The pups have so far been healthy and do not seem to have any illusions that they are fur seals despite spending the first few weeks of their lives living with them as neighbours. It is believed that in finding a spot behind a fur seal colony Kotahi has successfully disguised her presence from dominant adult males that can cause problems for the females and pups by their overeager and boisterous behaviour.

As she is not tagged we do not know how old Kotahi is or where she was born but Jim Fyfe from DOC believes that she could be from the sub Antarctic islands, 600 kilometres to the south of the mainland. We do know from DNA research that she has no direct relationship to any of our local sea lions but that her pups do, being fathered by local males.

We hope that she becomes a regular in her unusual fur seal colony habitat and goes on to have a long and productive life increasing the sea lion population for future generations to come.