Mystery and "hundreds of kilos of rock" continue to surround a massive whale fossil rescued from a North Otago lime works a year ago.
Discovered by Tokarahi lime works quarry workers three years ago, the 6m toothless baleen whale fossil is now housed at Museum of New Zealand Te Papa Tongarewa. Paleontologists, including the late University of Otago geology emeritus professor Ewan Fordyce, had been studying the fossil before it was removed at the end of last year as part of a rescue excavation to ensure the specimen was not destroyed.
The excavation took a team made up of Te Papa paleontologists Dr Felix Marx and Dr Alan Tennyson, the museum’s collections manager, museum volunteers and University of Otago and Victoria University students two weeks.
At the end of last year the team removed the fossil in four large chunks.
Dr Marx, who is an honorary senior lecturer at the University of Otago, said it had taken a "lot of luck" for the fossil to be preserved, and it would have taken a lot of luck for the bones to survive scavengers, bone-eating worms, pressure, heat or any deformation of the rock that could partially destroy the fossil while in the rock, and for the fossil to be discovered.
As the whale fossil was part of a "rescue excavation" other works might be prioritised at the museum over it, but the other reason for any delay was also due to the length of time in fossil preparation, Dr Marx said.
It could take weeks or months to chip away slowly at the chunks the team extracted.
"There are hundreds of kilos of rock, maybe more, across the four blocks, so working on that fossil itself will probably take a year easily," he said.
Dr Marx said the aim was to continue to work on the whale fossil and develop a productive plan to discover what had been found.
"We don’t know yet whether it’s a known species or an unknown species, or exactly how much of it is there."
He said trying to learn more about the variability of the species was very difficult, especially with a large fossil, because researchers often only found one or two specimens.
"These fossils are not necessarily complete either, so the whole process of preserving and then finding and working on a fossil is very much guided by chance," Dr Marx said.
Tokarahi lime works owner Brett Jones said the fossil was first dug up by quarry machine operators.
He said a former quarry manager had contacted Te Papa about the whale bones.
"This fossil had been out there for a long time and the guys always worked around it," Mr Jones said.
Dr Marx said he first saw the fossil when he was a PhD student at the University of Otago with his supervisor, Prof Fordyce, who, before his death in 2023, had spoken to the university about the fossil.
Dr Marx, who specialises in marine mammals, said the area’s limestone deposits were the result of the continent of New Zealand sinking and being flooded by sea millions of years ago.
It was out of one of these layers that the team excavated the ancient whale.
On the first field trip, in 2023, to view the fossil they initially looked at the exposed part of the fossil that was the head of the whale, Dr Marx said.
"There were two lower jaws exposed and we thought we would try to work back from there and see what was around that.
"We don’t know to start with how big a fossil is, how much is there, or how well it is preserved, where it’s sort of arranged more or less with the bones in the right place or not.
"We started digging around the skull and found that the fossil was relatively long".
The team decided to come back on a further dig and excavate the entire whale, Dr Marx said.
In the meantime, the impression he had of his visit was the whale fossil was "a symbol for the quarry that people could see and learn something about it, and the people working in the quarry were a bit attached to it", he said.
However, a full fossil lab was built a year ago at Te Papa around the same time the whale was collected from the lime works, which had given the museum the resources to work at "more of a capacity rather than in an "ad hoc way", Dr Marx said.
Questions still remained about what the whale fossil might reveal, he said.
"Once we know that ... there will almost certainly be a scientific publication on it."
