Prologue
The night is filled with the excited chatter of thousands of petrels, like school children in a distant yard. Closer, there’s the sounds of another animal: an eerie low, loud booming from several directions, felt rather than heard. And less frequently, the angry, sudden cat-like snarls of a skirmish, interrupted by a loud braying like a donkey. Suddenly, a loud electronic bell shatters my reverie, and I struggle out of the small tent into wet boots. In the dark I push through undergrowth to a low tussock marked by pink tape. I carefully nudge aside a curtain of grass fronds. Behind I see two gleaming white eggs, a bit smaller than a chicken’s. But these are no poultry eggs. Laid by one of the rarest birds in the world, these two alone represent nearly 2% of the world’s population. They are the eggs of a Kākāpō, and are the first laid by this particular female in 35 years.
Description
The Kākāpō (Strigops habroptilus) is one of the world’s rarest birds. With just 148 remaining and found only on four island sanctuaries around New Zealand, it is critically endangered. For decades it has been on the brink of extinction.
It is also an oddity. Charismatic and camouflaged, it is huge, nocturnal and ground-dwelling: the world’s largest and only flightless parrot. Secretive and solitary, it is entirely herbivorous, feeding on plants, roots and fungi on the forest floor, and on leaves and fruits high in the canopy. It has a reproductive system unlike any other bird, breeding only every 2-3 years in synchrony with the mass-fruiting of certain trees, such as the rimu, a southern conifer. It also has a highly unusual breeding system, as the only ‘lek-breeding’ parrot. In breeding years males congregate in large ‘arenas’ on high ground, digging scrapes, or ‘bowls’, joined by networks of meticulously-groomed ’tracks’. All night long, for months on end, they make a low-frequency ‘boom’ to attract females. The females visit males at their display sites, and mate with their chosen male (or males) in a process that can last over an hour.
That’s the only part the males play in the reproduction, and they return to booming. The female returns to a hollow tree or log in her home range, where she will lay up to four eggs. Feeding her chicks on a diet of vitamin-rich ripe rimu fruit, she will stay with them until independence more than 6 months later.
Decline
The Kākāpō was once one of New Zealand’s most common birds. Less than 150 years ago early European explorers describe huge numbers, shaking Kākāpō from trees “like apples”, being kept awake in bush camps at night by their calls, and finding 100 in a single mile. But introduced mammals – particularly cats, dogs and stoats – decimated Kākāpō numbers, exacerbating loss from hunting and habitat clearance by Polynesian and European settlers. By the 1940s few populations were known, and over 60 dedicated searches in Fiordland during the 1950s and 1960s found just 6 birds. By the 1970s Kākāpō were believed by some to be extinct and a last-ditch search was launched. Eighteen individuals were found in Fiordland, in the rugged south-west corner of the country – but these were all male. However, the same year a larger population was discovered on Rakiura/Stewart Island in the far south, and a breakthrough was reached in 1980 when the first female was found.
Recovery effort
The species could now theoretically be saved, but the Rakiura birds were being decimated by feral cats. The decision was made to transfer the birds to predatorfree offshore islands: Maud Island and Hauturu-o-Toi/Little Barrier in the north. The eradication of possums and weka (a flightless native rail that preys on eggs and chicks) from Whenua Hou/Codfish Island, 3km off the coast of Rakiura, formed another Kākāpō sanctuary. Breeding on these islands was sporadic, and when the population had reached an all-time low of just 51 individuals in 1995, the Kākāpō Recovery Programme (KRP) was formed to address the decline. With a dedicated team run by the Department of Conservation, efforts to prevent the extinction of the Kākāpō switched from rescue to science-driven conservation management.
Conservation Management
The KRP has become one of the most intensive and advanced species recovery efforts, driven by bold management and novel technologies. Every Kākāpō wears a VHF radio transmitter, which not only helps locate the bird, but also reports their activity for monitoring health and breeding. ‘Checkmate’ transmitters on males detect matings, and turn on a receiver to identify the female, reporting back the female identity, and the duration and ‘quality’ of the mating. The ‘Egg timer’ transmitters on females provide alerts when a female starts incubating eggs. A network of data loggers receive information from these transmitters, and transmits the data via satellite so that breeding can be monitored in near-real time from anywhere in the world.
Since breeding only occurs every two to three years, it’s essential to maximise production. All adults are provided with extra pellet food to ensure they’re in optimal breeding condition, and each has a `smart’ lockable feeding station which only that individual can access. Automatic scales at the feeding station provide remote monitoring of weights. This system allows the amount of food each Kākāpō receives to be controlled, to keep females within a certain weight range. This restricted diet is a result of research which showed that females fed too much food produced too many males – a result of sex allocation theory. The resulting personalised feeding regimes has since swung the sex ratio of offspring back to near-parity: the first time such manipulation has been done in an endangered bird species.
Kākāpō nests are closely monitored. Each is installed with an infrared camera, and an infrared beam which alerts a ‘minder’ in a nearby tent when the female has left the nest. The minder then checks the health of the egg or chick. Each nest also has a proximity sensor which transmits to the central hut on the island, so rangers can remotely monitor each nest. The system remotely monitors each female’s arrivals and departures, her activity on the nest, and even alerts of ‘stranger danger’ when another Kākāpō turns up – males have been known to injure or even kill chicks in nests.
Eggs are replaced in nests with fake ‘dummy’ eggs, and incubated artificially, because the team has more success hatching eggs than the Kākāpō do. Recently-hatched chicks are returned to nests to be naturally raised by their mother. Chicks are routinely swapped between nests to maximise survival. Kākāpō mothers are extremely forgiving, readily accepting and feeding another mother’s chick immediately – and also occasionally cope with having a chick replaced with an egg!
The aim is to keep at least one chick per nest, but a surfeit of chicks and ill health means that many chicks have to be hand-reared in captivity until fledging. This provides an opportunity for advocacy, with the hand-rearing facility on the mainland being opened to the public, so many people can have the rare experience of seeing a live Kākāpō. When old enough, the chicks are returned to the islands, weaned for a few weeks, and then released into the wild.
Conservation team
The Kākāpō Recovery Programme is science-led, with most conservation management decisions based on research evidence. The research is diverse and covers many aspects of Kākāpō ecology: such as nutrition, with the manipulation of sex ratios through supplementary feeding, and artificial insemination to improve genetic representation and fertility – another world-first when the team produced offspring from this method in 2009. Research efforts underway include a study into vitamin D – which is at very low levels in Kākāpō blood, despite rimu fruit being a vitamin D ‘superfood’ – and genetics, with a programme just completed to sequence the genomes of all living individuals (and some dead ones – 170 genomes are available). The team are also fitting GPS receivers to Kākāpō, to learn more about their habitat use, breeding behaviour, and interactions to help with disease research.
With such a diverse range of research topics, outside help is needed. Scientists from around the world lend their expertise to the conservation efforts, with contributions from nutritionists, veterinarians, geneticists and microbiologists, among many more. The KRP sets the research priorities and coordinates the research programmes, but Kākāpō conservation science research is very much a collaborative effort.
Funding & citizen support
As a part of DOC, the KRP is government-funded, but relies heavily on external funding sources. DOC’s National Partner, Meridian Energy, a renewable energy company, provides funding to the KRP, enabling additional research work to be achieved. But public contributions to Kākāpō conservation are growing, with donations from supporters, and a symbolic adoption programme raising funds annually. Donations arrive from around the world, with many donors learning of Kākāpō through the team’s social media channels.
Public advocacy is a key focus for Kākāpō Recovery. Opportunities for the public to see Kākāpō are very rare, so the team maximise any chances that arise. Public viewings of chicks hand-reared in Invercargill are held each breeding season, and each year Sirocco, a special ‘ambassador’ bird, goes ‘on tour’ to his adoring public. The first hand-reared Kākāpō, hatched in 1997, Sirocco became imprinted on humans and so is not part of the breeding programme. But he contributes to the species’ recovery by raising awareness of the plight of the Kākāpō, and is the New Zealand government’s “Spokesbird for Conservation” – the only bird in the world with a government job! Making more people aware that Kākāpō exist is a central tenet of the recovery programme. As Operations Manager Deidre Vercoe explains, “People only care about what they know. We want every child in the world to know what a Kākāpō is, just like they know what an elephant or a tiger is.”
A lucky few members of the public get to contribute directly to Kākāpō conservation by helping in the field. Each breeding season the team is helped by up to 4 volunteers at a time on breeding islands (Whenua Hou and Anchor Island). Over 100 people, from all walks of life and from across the globe, help each breeding season by providing food for the Kākāpō, cooking for the team, or acting as ’nest minders’, sleeping in tents near each nest. The experience of living in close proximity to the birds has a profound effect on those lucky volunteers.
Breeding seasons
Breeding seasons are intense periods for the Kākāpō Recovery Programme staff. With the long hours and sleepless nights, the experience has been likened to looking after a new baby . Field work starts in October, when supplementary feeding begins. Mating usually occurs in January to February, and during this time artificial insemination efforts take place. A dedicated ’sperm team’, comprised of international experts and senior KRP staff, spends three to four weeks on Whenua Hou, inseminating females four to seven days after mating and conducting fertility research.
During this period the first nests are also found, and the breeding season starts to get really busy. All permanent KRP staff are deployed onto islands, with seasonal and short-term recruits making up a team of up to 30 on each island. There are many roles to fill: finding nests and making them safe, checking eggs and weighing chicks in nests, and monitoring and hatching the eggs and caring for the sick or surplus chicks in the island hand-rearing centre. Newly-hatched chicks require feeding every four hours, and there can be a lot of mouths to feed. Supplementary feeding continues throughout, with regular weights collected for each bird. That’s just the ‘bird work’: the logistics of running an island field base also occupy lots of time: ordering supplies, organising flights to move gear and people, maintaining power systems and computers, and finding sleeping quarters and enough food and meals to feed a hungry field team. The list of job titles is testament to this: “Power Ranger”, “Nest Minder”, “Feedout crew”, “Supp Food Guru”, “Nest Minder Minder”, “Field Technical Lead”, “Supervisor”. Work takes place around the clock, with team members finding nests and monitoring and feeding birds by day, and sleeping in tents at night to check on eggs and chicks. A ‘nest controller’ at the base oversees the comings and goings of each female, helps coordinate decision-making when issues arise, and records all the nest check results.
It’s a very intense period from January until May, when the first chicks fledge from nests. Then hand-rearing still continues on the mainland, until those birds are transferred back to the islands for weaning and release by July. Then monitoring of the new chicks continues for several months – inexperienced, they can get themselves stuck, until they begin to leave their mothers by spring. In all, the whole breeding process takes a year. Kākāpō seldom breed in consecutive years, so the team usually has a year to take stock, debrief, and prepare for the coming season – as well as plan and conduct the research which will shape the future conservation efforts.
The future
The intensity of a breeding season will happen again in 2019, after a three year gap. The breeding in 2016 was unprecedented in magnitude, with 34 chicks fledged, but 2019 is shaping up to be bigger still. The team can predict breeding two years in advance by analysing temperature differences between consecutive summers, and then get a measure of the likely scale of the rimu ‘mast’ by climbing the huge trees to count the fruit a year out. The rimu monitoring in 2018 revealed a likely super-abundance of fruit in 2019 – meaning that nearly all of the around 51 adult females will breed in 2019. The team are recruiting extra help and planning for what promises to be a bumper year.
But even though the Kākāpō population continues to rise, progress is slow and many threats remain. Infertility is the biggest problem: only about a half of eggs are fertile, and just 1/3 of eggs laid turn into chicks that fledge. This is likely a result of very low genetic diversity in the founding population, exacerbated by many of the old founder Kākāpō having produced few or even no offspring over the last 40 years. The team are hoping to be successful once again with artificial insemination to help counter both of these reproductive threats.
Disease is a constant danger in a critically endangered species, and Kākāpō are no exception. A condition called cloacitis (or, more descriptively, ‘crusty bum’) which first appeared in 2002 has affected 24 birds, killing at least one. The cause is unknown – is it a virus, a bacteria, an autoimmune condition? – and several research programmes are underway to find out.
A more positive problem for Kākāpō is one of space. The two main breeding islands of Whenua Hou and Anchor Island are almost full, and with Hauturu still being trialled as a Kākāpō site, there are no other suitable predator-free islands on which to put Kākāpō. This means that Kākāpō will soon have to be translocated to islands which contain stoats – albeit in low numbers. The team have identified Resolution Island in Fiordland as the mostly suitable option, bringing more than a century of Kākāpō conservation to a full circle.
For it was on Resolution Island where Richard Henry, the original ‘Kākāpō ranger’ and one of New Zealand’s first and most dedicated conservationists, first tried to save the species from extinction. In the 1890s and early 1900s he translocated hundreds of Kākāpō from the nearby mainland where they were being decimated by a wave of stoats recently introduced to New Zealand. That translocation failed, since stoats also invaded Resolution to the surprise of a heartbroken Henry. But with large-scale stoat control now in place, the team are confident that this time round translocation will be more successful. More than a century after his revolutionary efforts, the determination and ambition that Richard Henry brought to Kākāpō conservation provides inspiration to the team currently tasked with saving this most unique and charismatic bird. The fight goes on.
