The weka invasion of Whakata¯ne

The Eastern Bay of Plenty has seen an explosion of weka, with the birds even finding their way into shops. As Heidi Bendikson reports, weka pose an ecological conundrum and are not always welcomed, but if history is anything to go by, it may pay for locals to appreciate them while they can.

The nights are rarely silent on Jane Fitton’s lifestyle block, between Whakatā ne and Tā neatua. Not for the past three years anyway. She suspects the ruru are still there, but their calls are usually drowned out by a persistent screeching.

The high-pitched call is similar to that of kiwi.

It would not be surprising to hear the national bird closer to Whakatā ne, a town recently dubbed the Kiwi Capital, but the yoga instructor knows the nightly cacophony comes from another flightless bird: the weka, which are brazen enough to come into her yard in broad daylight, and help themselves to her fallen fruit.

She has seen them in town too, wandering around the Whakatā ne Countdown. In fact there have been a number of reports of weka making themselves at home in the town centre.

Naomi Biddle, fudgoligist at fudge and gift store Tui Aotearoa, had a weka wander into her store on the strand last month.

‘‘I just thought, ‘what the… weka?’’’ Knowing that weka can make a mess when startled, she just let it be until it was ready to walk out.

Merv Manssen, store manager at Beaurepaires, was standing at the front desk a few weeks ago when he looked up to see a weka sitting on the tyre display.

‘‘I was like, what the hell is that?’’

He was used to seeing weka when camping near Ō pō tiki, but this one would have had to cross busy Commerce St to get from the bush reserve to the shop. So, he carefully threw a towel over it and carried it back across the road to the edge of the reserve, all the while talking to it and giving gentle pats to keep it calm.

Just a few years ago, many locals would have never seen a weka in the bush reserve, let alone wandering along the main street.

While it may not seem so to Eastern Bay locals tired of weka ravaging their veggie gardens, or to South Islanders whose western weka are numbered in the tens of thousands, North Island weka are an atrisk species.

Their story begins on the other side of the Waioeka Gorge, in Taira¯ whiti. Department of Conservation (DOC) technical advisor and Weka Recovery Group lead, Rhys Burns, explains that weka were once widespread in the North Island, but for reasons not fully understood, their population declined to a point where, in the 1960s, they were only prevalent in the Gisborne region.

In the 1980s, these East Coast weka faced further rapid decline and small populations only remained near the town of Mo¯ tu.

‘‘They were down to about 1000 birds or so, which is pretty tenuous.’’

DOC began a predator control and monitoring programme in Mo¯ tu¯ , but Burns does not attribute those efforts to the population’s expansion.

‘‘We couldn’t really see any difference between treatment and non-treatment, and I think that was just a reflection that the weka were expanding for other reasons.’’ And expand they did.

Burns is careful to explain that the weka’s appearance in Whakata¯ ne was not a case of mass migration, as per local rumour. He says weka can still be found near Mo¯ tu¯ and it was a gradual expansion in their population which soon saw breeding pairs turn up in O¯ po¯ tiki, and later Whakatā ne.

Weka have a propensity for both rapidly expanding and rapidly declining – boom and bust cycles for which Burns has theories, but no clear answers.

‘‘It is a bit curious because in some places they do so well and they always have chicks and you think, ‘how could they ever die out?’, but something changes in their environment.’’

Those changes may come about from drought, disease and predation by mustelids. They are especially susceptible to ferrets, and the rumoured release of ferrets by Poverty Bay ferret farms when the industry crashed in the 1980s has been linked to their decline in Tairā whiti.

He says weka sometimes die of botulism in summer, possibly from eating carrion or other dead birds.

Burns says many North Island weka were relocated to North Shore Islands in the early to mid 20th century.

‘‘In some ways it was fortunate because a lot of birds were moved before the big crash in the 50s and 60s.’’

But their relocation was actually motivated by a desire to get rid of birds causing a nuisance rather than protecting their species.

Weka from captive stock were relocated to islands in the Hauraki Gulf in the 1990s as a protective measure for the species, some of which swam across to Waiheke Island. But weka can do more harm than good on off-shore islands usually used to protect species.

As an omnivore, weka eat not only fruit and seeds, but eggs and small animals. This has proven a problem for DOC in the past, and they have had to remove weka from some islands due to their predation of native lizards and ground-nesting birds.

In the Eastern Bay of Plenty, this sinister aspect of the weka is a bit of a sore point, with any community Facebook post about the bird (usually spotted inside a shop or carpark), soon followed by a comment about weka eating eggs and chicks.

As Fitton points out, ‘‘[Seeing the birds] was nice at first, but I think we have got to remember they are at the top of the food chain in the bird world and they seem to be very successful around here, so it is a double-edged sword really.’’

Weka’s predation of birds is of particular concern in Whakatā ne, where kiwi conservation efforts have been in place since 1999, when eight kiwi were unexpectedly found in the reserve between Whakatā ne and O¯ hope. The kiwi population now stands at around 300.

Gaye Payze, predator control coordinator for the Whakatā ne Kiwi Trust, says there is a risk of weka predating kiwi, but it is not their biggest concern.

‘‘We have seen on our camera an individual weka scrapping in front of a kiwi burrow and having an encounter with a kiwi male who wasn’t very impressed to have a weka in his burrow.

‘‘So there is a risk, but as to how much of a risk? We can’t say it’s a population level risk, rather it just seems to be an individual level so far. It’s not as big an issue to kiwi as stoats.’’

She adds that kiwi and weka have coevolved and lived together for a long time and live together successfully in Northland, but they are an avian predator that can put pressure on other endangered species.

Those thoughts are echoed by Burns: ‘‘They do have an impact on other species and sometimes even potentially threatened species, but you know, they’ve all survived each other in the past and predators keep things on their toes.’’

Payze does suspect Whakatā ne weka will be benefiting from the trust’s pest control efforts which were initially tailored for kiwi, especially their dog aversion training, which has now been broadened to train dogs to keep away from weka.

She says that all birds are vulnerable to dogs because their bones are so fragile and their skin can easily be torn from their backs, but wekas’ behaviour in particular can make them susceptible.

‘‘It’s just their natural behaviour. The weka, when you come close to it, it will give its shrieking call and just run and for a dog it’s just natural to chase something that’s running.’’

While many locals seem enamoured by weka, their proliferation can be a nuisance, with community Facebook page reports of the birds pillaging veggie gardens, stealing fruit and defecating indoors.

While Fitton has no problem with weka, finding them ‘‘cheeky’’, she can see how their boldness could be a problem for some.

‘‘They are very very bold and they are cheeky and I’m glad that we don’t have anything other than our veggies and fruit that we feed ourselves that can be damaged by them.’’

Burns points out that the Wildlife Act prevents anyone from killing or moving weka. No-one has been prosecuted, but he has seen evidence of the birds being relocated: a dramatic shift in the population and damage to the birds’ bill, suggesting they have been caged. It has been suggested that their sudden appearance in Taranaki may have been from such relocation.

Fiona Powell, a marketing manager from Katikati, thinks weka have had a bad rap. Since 2015 she has campaigned for weka to be bird of the year.

She spent a lot of time with weka when she lived on a private Hauraki Gulf Island, Pakatoa, so she took the opportunity to photograph them and spread the word about the weka’s unique characteristics – catching rats and even swimming across to another island.

‘‘People kind of love or hate them. Everyone has got a weka story about when they have been tramping down south and the weka have stolen their socks, or their car keys. They are just such a cool and cheeky bird. They have got so much charisma.’’

In researching the birds, she found admiration for weka in the work of poet, Eileen Duggan, who wrote of the bird in the mid-1900s: ‘‘You’re gay as a gossip and vain as a man-child.’’

Adding, in acknowledgement of decline of weka in the lower North Island at the time, ‘‘but it’s my pity your footprints grow rarer; little brown mischief, don’t slip from our sight’’.

Powell also discovered accounts of West Coast explorer, Charlie Douglas, who admired weka so much that he suggested they, not the kiwi, should be the New Zealand’s national bird. And she agrees.

‘‘Most of us have never seen a kiwi, but now we have had weka flourish, we have a real opportunity to see weka.’’

When not pillaging veggie gardens, however, weka can be useful to have around. Gaye Payze from Whakatā ne Kiwi Trust says that, while weka are threatened by pests, they can sometimes give as good as they get. She refers to a viral video of a weka attacking a stoat and anecdotal accounts of weka living in backyards keeping rats and mice at bay.

They can be crucial for seed dispersal too. A 2019 study reported in the New York Times found that weka were important seed distributors, especially for larger seeds such as miro and hinau. However, the Eastern Bay’s urban weka might not be contributing much on this front.

The study noted that weka that spend too much time with humans, scavenging their food, are less effective seed dispersers.

Even though kiwi are the focus of Payze’s role with the trust, she too thinks local residents should appreciate and learn to live with the weka.

‘‘I would just like people to respect weka as much as kiwi. They are one of our native species,’’ she says, adding that it is important to watch for them on the road, because there have been fatalities.

Rhys Burns from DOC acknowledges that weka can be challenging, but locals can take precautions, such as covering and fencing veggie gardens.

‘‘We kind of have to learn to live with weka. They are actually pretty lucky to have them. There are not many places [that do].’’