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Over the past few months, I鈥檝e had the pleasure of diving deep into the聽, an initiative that鈥檚 steering the world鈥檚 army of birdwatchers, conservationists and researchers towards finding 10 of the most enigmatic and important bird species lost to science. There have already been some successes 鈥� including the extraordinary rediscoveries of both the聽聽and the聽. Now, an extensive search is underway in New Zealand for the mysterious South Island k艒kako, which has become a surprising icon for the nation鈥檚 struggle to save its unique bird species from invasive predatory mammals.
There are no photographs of the South Island k艒kako, a large blue-grey bird with two fleshy orange flaps known as wattles at the base of its curved black bill. Like many of New Zealand鈥檚 endemic bird species, it suffered great losses due to deforestation and the introduction of mammals such as ship rats, stoats and feral cats. The last accepted sighting of the species was in 1967, and it was declared extinct in 2007 鈥� however, a sighting that same year led to its reclassification as 鈥渄ata deficient鈥�. In 2010, the聽聽was set up to find it and has been searching ever since.
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In 2017, the trust launched a public campaign, asking anyone going deep into backcountry areas to look for the bird and report sightings. 鈥淎fter that, we started getting heaps of reports,鈥� trust manager Inger Perkins told me, but no one has yet won the NZ$10,000 the trust is offering for evidence confirming the elusive bird鈥檚 existence.
The campaign, though, has helped make New Zealanders care about this missing bird in a country that鈥檚 already filled with unusual and threatened bird species, from the聽聽to the聽. Perkins says that before the trust began drumming up interest, the South Island k艒kako got very little attention. There was, however, awareness of the closely related North Island k艒kako 鈥� very similar except that its face wattles are blue 鈥� which has been brought back from the edge of extinction and features on the nation鈥檚 $50 bills.
Like many of New Zealand鈥檚 recent conservation successes, the preservation of the North Island k艒kako has involved thorough efforts to kill mammalian predators. 鈥淲herever it鈥檚 surviving, it鈥檚 needing regular and intensive trapping to keep the predators down,鈥� says Perkins.
The future of many of New Zealand鈥檚 birds depends on the success of聽, an ambitious and difficult project to eliminate rats, European stoats and Australian possums from New Zealand by the middle of this century. Trapping and killing these mammals is one technique that鈥檚 being used. Another is dropping poisoned bait by helicopter in unpopulated areas.
鈥淭here鈥檚 a huge lot of people who just hate the idea of poisoning the forests. But it鈥檚 the only major tool, particularly in large, remote areas, for predator control,鈥� says Perkins. She says that projects like the search for the South Island k艒kako help to get the public on board with these kinds of measures, helping people to realise that 鈥渙ur forests are not what they used to be, and we do need predator control鈥�.
So, how do you go about finding a South Island k艒kako? One intriguing line of inquiry is collecting and analysing audio recordings 鈥� a surprising tack to take, given that no definitive recording of the bird鈥檚 call exists. However, it鈥檚 thought to sound something like its North Island cousin, and to be a haunting call with organ and flute-like notes and some other sounds mixed in.
Using this as a starting point, mathematician聽聽at Victoria University of Wellington algorithmically generated every conceivable variation of this kind of call, and has used these to comb billions of hours of audio recordings from different locations for possible South Island k艒kako calls. In this way, his team was able to identify 250 possible calls, and then narrowed these down further to only five, which are now under review by experts.
But in all the 13 years that the trust has been looking for the South Island k艒kako, no definitive evidence has yet come to light. Every year at the trust鈥檚 annual meeting, Perkins says they ask themselves, 鈥淚s there still value in us putting this effort in?鈥�
What could be the trust鈥檚 final searches are now underway, scouring key areas in the north-west of the South Island. 鈥淚t鈥檚 going to be more recorders, more cameras, more hands on the ground 鈥� almost like a police search across the hillside where there鈥檚 been a murder,鈥� says Perkins.
I鈥檓 waiting eagerly for news of how these searches have gone. In a country filled with charismatic bird species, I can鈥檛 quite believe that the South Island k艒kako has garnered so much attention, with passionate volunteers manning extensive and difficult searches.
But speaking to Perkins helped me understand the wider significance of such projects 鈥� even if the South Island k艒kako is never found, it has acted as a conservation icon, helping us all to understand what鈥檚 at stake in New Zealand.
