The world’s leading expert on Foulden Maar has once again been locked out of the prolific palaeontological site — but this time by the Dunedin City Council.

University of Otago geology Emeritus Prof Daphne Lee was at the forefront of the bid to protect the prehistoric volcanic crater near Middlemarch from mining interests several years ago.

Now she said she was disappointed to learn her long-awaited return to the site was considered a "one-off" by the council.

Prof Lee returned to the globally significant site late last year with a small group of scientific researchers after being barred for about five years when the maar became embroiled in a mining controversy.

Foulden Maar was to be mined by Plaman Resources, but the company went into receivership in 2019.

The city council ultimately bought the fossil site, saying at the time it would prevent mining on the land and "preserve this very special scientific and conservation site into the future".

When a five-year consent for researchers to return was granted late last year, Dunedin’s scientific community celebrated the return of researchers to Foulden Maar as a victory for science.

So prolific is the site that the first group of scientists to return, who were in Dunedin for last year’s Geoscience Society of New Zealand conference, discovered a likely new-to-science 23million-year-old ant at the maar after just a couple of hours.

However, a return visit is not in the cards in the short term it would seem.

Prof Lee told the Otago Daily Times for several weeks this autumn she tried to arrange follow-up visits.

After at first receiving no reply from the council, she ultimately received a "very disappointing" email from council chief executive Sandy Graham.

Ms Graham told Prof Lee she knew her return to the site was a "one off" and future visits would not even be considered until October.

"As you know, we made a one-off arrangement last year," Ms Graham’s email last week said.

Prof Lee disputed this.

"I didn’t know it was a one-off.

"They didn’t tell me it was a one-off."

A five-year consent was granted on November 22 last year that allowed a group of up to 20 scientists, students and support staff to access the site no more than once a month and excavate 0.5cum per visit.

Prof Lee said she believed the consent would allow her to resume research and once again collect fossils from the site, which was why she had asked to visit with a group of students at the start of this month.

"I’ve given three talks in the last three weeks about Foulden Maar and I’ve got more coming up.

"I was confident that visits would be allowed because I now have this five-year consent and it didn’t occur to me that it was for one visit at the end of November and never more."

Nevertheless, Ms Graham told the ODT the council’s position "remains unchanged".

"We’re preserving the fossil record at Foulden Maar while considering the best ways to manage future public access to the site.

"A report on these issues has always been planned and is taking time to complete due to staff workloads, but we’re hoping to have it in front of councillors before the end of the current triennium in October."

Applying for the five-year consent was merely a matter of efficiency, she said.

The council approved Prof Lee’s request to visit the site with a small group as part of the geoscience conference and in order to do this needed to obtain resource consent.

Rather than apply for additional consents each time a group wanted to visit, the council applied for one five-year consent that allowed for multiple visits, Ms Graham said.

"This was a pragmatic approach in the interests of efficiency, but I met with Prof Lee at the time to explain to her that although the consent allowed for multiple visits, she would only be permitted to take one group on site initially.

"Future visits would be subject to the issues of access being resolved, as well as consideration of health and safety factors and the interests of the landowner whose property — a working farm — surrounds the Foulden Maar site."

The staff report being prepared for councillors to consider would examine the best way to manage these various issues.

"I acknowledge this small delay does not suit Prof Lee, but she has been kept fully informed throughout this process."

hamish.maclean@odt.co.nz