An artists impression of an elasmosaurus, an enormous marine reptile from the Late Cretaceous period that could reach up to 14 metres long. The fossils contain what are thought to be remnants of an elasmosaurus skeleton. Illustration / Getty Images
A treasure trove of taniwha fossils unearthed in northern Hawke’s Bay as a result of Cyclone Gabrielle scouring of the landscape will rewrite the New Zealand fossil record.
Maungataniwha native forest, and specifically the Mangahouanga Stream, have been a hotbed of fossil finds since renowned New Zealand palaeontologist Joan Wiffenand her team discovered New Zealand’s first dinosaur fossils there in 1975.
About a dozen previously undiscovered fossils, some thought to be about 80 million years old, were discovered in March while staff and volunteers from the Forest Lifeforce Restoration Trust were assessing storm damage in the forest. Scientists have recently been able to begin identifying them.
Pete Shaw, forest manager of the Forest Lifeforce Restoration Trust and an experienced fossil finder, said they had not had a find with fossils of this size and number before in his outings to the area.
He said the most notable were two lumps of fossilised vertebrae that appeared to be part of a large spinal column.
“Both of them have got a series of vertebrae, one of them has got four big vertebrae, and I mean they are big, they are probably 200 millimetres across, they are massive,” Shaw said.
Shaw said the area had been hit hard by Cyclone Gabrielle, with over 200 kilometres of road and quad bike tracks requiring repairs, but the fossils were one bit of good news.
“The block out there has been just smashed to bits,” he said.
“We’ve got a huge job ahead of us, but we are getting there.”
Marianna Terezow, National Paleontological Collection manager for GNS Science, has identified two large fossil vertebrae as potentially being from an elasmosaurus - an enormous marine reptile from the late Cretaceous period that could reach up to 14 metres long - from photos of the fossils sent to GNS.
Other vertebrae discovered in the bunch may have come from a mosasaur, a marine reptile from the late Cretaceous period.
“The identifications we made were based on general characteristics of the bone, where obvious, as well as comparisons with material previously found in the area, supported by our knowledge of the geology and paleobiodiversity of the Maungataniwha area,” Terezow said.
“Based on the images, the vertebrae appear to be about 8-10 cm in size, so these extinct animals would have been very large.”
The finds were comparable to fossils previously found in the Maungataniwha area and appeared to all be marine fauna, most of them being marine reptiles like elasmosaurs.
She said floods and excessive water erosion of river beds, steams and coastlines can upturn large amounts of sediment and rocks, revealing new exposures.
“If the geology of the area is conducive to fossilisation, then yes, you could end up with new and exciting fossil discoveries,” she said.
“The recent Maungataniwha finds are the only new fossil finds of this extent that I’m aware of, but it’s highly likely other areas in Hawke’s Bay have new outcrops with fossils.”
James Pocock joined Hawke’s Bay Today in 2021 and writes breaking news and features, with a focus on environment, local government and post-cyclone issues in the region. He has a keen interest in finding the bigger picture in research and making it more accessible to audiences. He lives in Napier. james.pocock@nzme.co.nz