There are always lists of unanswered questions, gathering dust in the corridors of research institutions. Often the hurdle to answering them is not an intellectual dead end or riddle, but something as mundane as not having got to it yet - the creeping delay of logistical box ticking. Such organisational challenges have always prevented scientists reaching the tiny albatross population living on Three Kings Islands. The rocky islets are located 60km north of New Zealand where the south Pacific Ocean and Tasman Sea converge. A bird of mythological significance in European and Māori tradition, the species of Buller's albatross is endemic to New Zealand waters. This is the journey to find a new subspecies. If the 30-odd Three Kings albatrosses are genetically isolated they will be critically endangered. It will be a discovery that occurs in New Zealand conservation barely once a decade.
As he sits in his Auckland Museum backroom office filled with jars of decomposing birds, Matt Rayner is open about the difficulties of an expedition he describes as a "career highlight".
For the museum's curator of land vertebrate it's been a four-year journey. For the New Zealand ornithology (bird) research community, much longer.
"Basically in terms of seabird conservationists, it's been on the list of things that need to be done for a very long time," Rayner said.
"But it's 60km off the mainland, and exposed steep 50m high rock, exposed to southwesterly swells, that you can't land a helicopter on. So no one had done it yet.
"It's taken us four years to get to a point where we could get out there with Ngāti Kurī and get it done.
"But it's been on the list since 1984 when the population was discovered. It's been a question mark."
He's talking about a journey to Three Kings islands, Manawatāwhi, undertaken by a select group of researchers and Far North iwi in late February.
Their target was a tiny population of albatrosses which for, whatever reason, have chosen the smallest craggy islet of a cluster of 13 rock islands to breed and call home.
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Rayner will eventually determine whether this group of just 30 to 40 seabirds is a new species of the near threatened Buller's Albatross.
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The nearest population of the elegant silver-grey seabird is the Chatham Islands - 1500km away.
And if this were a distinct subspecies only breeding among themselves it would make it critically endangered, in need of urgent conservation.
"The big question for conservation managers, for scientists and for mana whenua is: are these birds on a little rock stack in the middle of the ocean unique?
"If it was genetically isolated it would be of very high conservation threat category. The next question would be well, how can we help this population?"
The trip: 'A story of isolation'
As much as the expedition to Three Kings Islands was Auckland War Memorial Museum's conception, the journey was equally orchestrated by the local iwi of Ngāti Kurī.
A team of five travelled by boat to the rock stack 60km northwest of Cape Reinga - New Zealand's northernmost point.
This included tube-nosed seabird expert, Rayner, his friend and professional conservationist Kevin Parker, Auckland Museum photographer Jennifer Carol and two representatives from Ngāti Kurī: Thomas Hvid and Trenton Neho.
On February 26, the Auckland Museum team drove five hours from Auckland to Houhora Harbour in Northland to unite with the Ngāti Kurī team who had overseen an extensive quarantine process of their gear, sent up earlier.
"These islands are pristine. They're like New Zealand was centuries ago," Rayner said.
"In quarantine your gear must be washed in a disinfectant that kills any kauri dieback or nasty diseases, clean the seeds. It's all checked and put in sealed containers."
"The history of Manawatāwhi is one of isolation. The island group is far away from mainland New Zealand but in the last ice age was connected to the mainland.
"So this island group is very special, it's a nature reserve of the highest conservation category and it's got many unique and endemic animals and plants only found there: skinks and geckos, trees, and potentially also albatrosses."
On February 27, the team of five ventured before dawn by motorboat 90km from Houhora to Cape Reinga, and then 60km northwest in open sea to Manawatāwhi - a four-hour journey.
The trip had been scheduled precisely for a day when the sea would be at its calmest during January, February and March.
But despite best intentions, when the boat arrived at Manawatāwhi, the sea was rough.
Rayner, Parker and Carol had to land on Rosemary Rock - the one particular island where the population of 30-odd Buller's albatrosses choose to breed.
"We left Houhora before dawn. When we got there we had to cruise around the rock for quite some time figuring out the best place to land because there was quite a big swell surging. And the best spot to land wasn't necessarily the best spot to climb up," Rayner says.
After debating the best course of approach while sheltering in calmer waters behind one of the surrounding islands, the trio of Rayner, Parker and Carol made a 15m splash for Rosemary Rock on the sheltered side of the swell.
"We had to make a swim for it into a rock platform with our wetsuits, booties, gloves, and then pull our gear ashore with life jackets: our waterproof backpacks, a barrel with Jenn's camera gear," Rayner says.
"It was rougher than we'd hoped - a lot of current, really strong. But it was a bloody exposed, not flat by any means. It's in the middle of the Tasman Sea."
Once changed into dry clothes at the base of Rosemary Rock, Rayner had to guide Parker and Carol up the safest route of the approximately 50m-high rise to where the albatross population were breeding.
In his Auckland Museum office a week later, Rayner flicks through the extensive health and safety leaflet the team had devised.
"We're used to working around steep terrain in this island work, but if you make one mistake you're dead, that's not in the health and safety plan," Rayner says.
"We didn't put ourselves in situations where a fall would result in death. There were some places the birds were we didn't go."
The group tracked a rough course up the rock to sheltered locations where the Buller's albatross chose to nest.
A 2017 study on seagulls in northern New Zealand helped guide the climb.
"This paper came out and they had flown an aeroplane over all seagull colonies and took high resolution, including at Manawatāwhi, so we had high-res aerial imagery of the rock we were able to look at," Rayner said.
However, with the exception of "one little tricky bit, steep bit about head high" Rayner said it was relatively straightforward.
"We kind of already had an inkling where they were from this layout. And they were there," he says.
The next step was to physically grasp several birds.
This posed a slight challenge.
"It wasn't ideal because when the birds are sitting on eggs, they're all there to be captured," Rayner says.
"But these birds were feeding chicks, so there weren't that many adults. We captured enough: three adults and four chicks. Seven blood samples."
Albatrosses actually need the wind at their back to take off, and it was a detail Rayner and his team took advantage of on the sheltered southern slope of Rosemary Rock.
"I was very lucky I had a colleague with me, Kevin Parker from Parker Conservation, who is very experienced with albatross," Rayner says.
"These birds are very unique, they've evolved at their breeding sites without people, without cats and dogs so they actually don't have a fear response.
"They are quite large birds, a number of kg, and they need a run up to get airborne. If you approach from downwind, they can't take off. You approach very slowly and it's just simply a matter of grabbing the bill and quickly putting your arm around them.
"Then we took a blood sample with a syringe for genetic analysis, body measurements and high-resolution photos of the birds for comparison."
Working as quickly as possible, this process can take under five minutes.
After an intense four hours on Rosemary Rock inspecting the birds, it was back to the boat around 4pm, and a long return journey back to land at Houhora around 8pm.
"It's special for me, a career highlight," Rayner says a week after the journey.
"I've never been to the Three Kings, so it's pretty awesome. My preference would have been to go for longer but it was a wicked experience to get there. I mean it was full on, it was go, go, go.
"We were knackered. It was a big day, field work is hard to organise, co-ordinate, find the funding, get the permissions, engage with the stakeholders.
"But everything pretty much went to plan. It was cool."
The next step in identification: DNA analysis
With blood samples of the Three Kings albatross population secured, a group at the University of Otago will now undertake DNA analysis, and potentially map the genome of the birds.
This will take several months.
"A paleogenetics lab are going to do the analysis of those blood samples, and they're going to look at different mitochondrial and nuclear DNA of these birds and compare them to the existing DNA in databases for the other [Buller's albatross] populations," Rayner said.
"We're also going to compare the high-resolution imagery we took of these birds between populations, and the measurements."
Around New Zealand waters there is a breeding population of around 13,000 Buller's albatrosses.
In addition to their geographical isolation, one distinguishing characteristic of the Three Kings albatross compared to populations in the Chatham Islands is their slightly smaller stature.
"We don't know [if the population of 30-40 albatross on Rosemary Rock is breeding with any other albatross]. The key questions are: what degree of gene flow is there? Are these birds related to birds further south? If they're not, the DNA is going to show there's absolutely no gene flow.
"If Three Kings are genetically isolated it would be of very high conservation threat category. All populations fluctuate over time. Small populations can fluctuate really easily to zero. So it would be an immediate concern."
Rayner says there are conservation efforts to bolster the population that could be implemented immediately.
"I've been involved in some projects where we've used 3D printed dummies of birds to attract them to breed at new locations. So there's actually a bit of habitat on Three Kings' [other islands].They only use this one little rock stack," Rayner says
"So potentially we could use dummy albatrosses to try and attract birds to breed at other locations."
If this tiny group of Manawatāwhi Buller's albatrosses were genetically isolated it would be a significant discovery for New Zealand taxonomy.
In response to the question: how often a new subspecies of bird would be found in New Zealand, Rayner replies "not that often".
"Much more common in other things like insects and plants, but it's not very common in birds. Every five to 10 years in New Zealand [in birds]."
Regardless of whether the Three Kings albatrosses are unique, a paper on Auckland Museums February 27 expedition will "naturally" be published in a genetics journal at some point.
Yet, for Rayner, this is not the priority.
"Ten per cent of all seabirds [globally] breed in New Zealand. Because we're a small island in the middle of a massive ocean, and within those tube nosed seabirds, albatross are super endangered - I think 15 of the 22 species," he says.
"All my work at the museum is towards using science for conservation."
Fostering a relationship between Ngāti Kurī and Auckland Museum
The journey to reach Three Kings Islands/Manawatāwhi was not just to fill a gap in scientific knowledge, but also to mend a disconnect in culture.
Around seven years ago, far north iwi Ngāti Kurī approached Auckland Museum and the Department of Conservation, unhappy with the level of field research going on in Northland without any collaboration with them.
Ngāti Kurī trustee Sheridan Waitai facilitated the logistics for the February trip to Manawatāwhi, and is also overseeing three other conservation efforts on islands north of New Zealand.
Representatives from Auckland Museum now annually visit Ngāti Kurī over four-day seminars to share information and collaborate in person.
She says the road to trusting Auckland Museum and DoC has been a long, but profitable, road.
"They didn't just come and take samples of plants. They actually took dead body parts, a range of things from sacred places and put them all in their museums and locked them away," Waitai says.
"So scientists really did not have a good reputation and neither did DoC. We pretty much requested a whole reset of that relationship, and over a period of time built the research programme."
The seven-year journey to trusting and working with Auckland Museum has had practical goals.
"For us we had to understand how we could best advocate for more resources to help real endemic species, not just the albatross, but other species on Manawatāwhi not found anywhere else," Waitai says.
The untouched predator-free cluster of 13 islands under increasing threat of encroachment from the public in Ngāti Kurī's eyes - threatening the ecosystem.
"We have more of the general public trying to get up there with charter boats. It's only a matter of time," Waitai says.
The Manawatāwhi islands are part of Ngāti Kurī heritage.
"In times of warfare on the mainland Manawatāwhi was a place where women and children were ferried out on ships and kept safe. It's protected our lives for future generations," Waitai says.
The two Ngāti Kurī representatives on the boat to Manawatāwhi on February 27 were Trenton Neho, 23, and Thomas Hvid, 22.
Along with participating in the pre-quarantine for the trip, Neho and Hvid added a cultural gesture to the research team's time bobbing on the Manawatāwhi seas.
They caught a fish.
"We really encourage all our young leaders who go back to the islands, even though they've got to do the work, they've got to have fun," Waitai says.
"So it's about the see, feel, touch, smell, taste, the place of your ancestors. It's really important for us that they have food and eat from the same place as their ancestors."
The experience for the Ngāti Kurī descendants was a personal revelation.
"It was the best day of my life," says Hvid.
"I wanted to live out there. The wildlife is stunning and absolutely flourishing. A place of dreams."