Rare baby ghost shark found off the South Island

Ghost shark embryos develop in egg capsules laid on the sea floor and feed off yolk until they are ready to hatch. Photo / Supplied

By RNZ

A days-old ghost shark has been discovered during a recent survey off the east coast of the South Island.

The newly hatched deep-water shark was collected at a depth of about 1200m on the Chatham Rise.

"You can tell this ghost shark recently hatched because it has a full belly of egg yolk. It's quite astonishing," Niwa fisheries scientist Dr Brit Finucci, part of the team that made the discovery, said.

Also known as chimaeras, ghost sharks are relatives of sharks and rays. Their embryos develop in egg capsules laid on the sea floor, and feed off a yolk until they are ready to hatch.

Newly born ghost sharks are rarely found and little is known about them, she said.

"What we know about ghost sharks, which is very little to begin with, is mostly from the adult animals," Finucci told Morning Report.

"It's very, very rare to actually find one that fits in the palm of your hand."

Finucci said the discovery would help fill in some of the gaps in knowledge of the species.

The baby shark was discovered during a recent trawl survey to estimate abundance of hoki. The survey is carried every two years and also looks at non-commercial fish species.

Further tests and genetic analysis would need to be carried out to determine the exact species.

Juveniles tended to be found in different areas and depths to adults.

"From some of the better-known ghost shark species we also know that juveniles can eat very different things from adults. They can be eaten by a whole wealth of fish as well.

"We know just from a couple of species that juveniles can actually look very different from the adults too.

"Everything that we can collect fills in some knowledge gaps from these very, very data-poor species."