Hon Dr Nick Smith, NELSON MP
29 January 2014, Nelson Yacht Club
2014 marks the centenary of World War I, it’s the year of our triennial general elections and it’s the year of the Rio Football World Cup. The topic of this year’s Rotary speech is not about military, political or sporting battles but a little-known battle in our vast forests between pests and our native birds.
I am pleased to be leading this difficult debate. When I came to national politics 25 years ago as a young applied scientist, my ambition was to make a useful contribution towards improving New Zealand’s natural resource management. I wanted reason and evidence to trump politics and prejudice. This issue of how we respond to the 2014 beech mast and its plague of predator pests essentially comes down to whether we are serious about the survival of birds like the kiwi, and whether we will back the science to do what is necessary to save them.
Let me begin by putting this debate in a broader context. New Zealanders rightfully fret about how well we match up to our clean, green brand. It matters to our view of ourselves, our lifestyle and our economy. The millions of tourists who come here marvel at our majestic mountains, rich green bush, weird and wonderful birds and crisp clean lakes, rivers and beaches. We do get a premium for our dairy products, fish, fruit, meat, wine and wood because of our good environmental credentials. The point few New Zealanders appreciate is that our most significant environmental challenge is the decline and extinction of our native species.
Here are the numbers on how we compare with the other 193 countries in the United Nations. If we look at what proportion of our land area is protected in reserves, we rank seventh best. On the proportion of our energy that is renewable, we rank eighth. On air quality, we rank fourteenth. On water quality, we have work to do – we are 43rd but still in the top quarter. Here’s the clanger. New Zealand ranks 193rd – i.e. rock bottom – for the proportion of our animals at risk of extinction.
I accept there is a bit of contention over these sorts of international comparisons. Measuring environmental performance is even more difficult than economic measures like GDP. However, all the scientific literature points to New Zealand’s biggest environmental problem being species decline and loss, particularly for our birds.
The reason we have 179 of our 690 native animals in trouble is our unique geological heritage. For 60 million years after New Zealand split off from Gondwanaland, we had no mammal predators. This meant a whole range of flightless birds and unusual creatures like tuatara and giant weta evolved different to any other land mass. To emphasise the point, the islands of the United Kingdom which are about our size and where so many of our ancestors came from, has only one unique native bird – a rather boring species called the Scottish crossbill. In contrast, New Zealand had over 100 endemic birds that are unique and exist nowhere else.
Last century we lost a number of significant birds. The huia in 1907, the laughing owl in 1914, the piopio in 1963 and the South Island kokako – with its orange rather than blue wattle – has not been seen in more than 30 years. Nor has the South Island pateke, or brown teal, since the 1990s. The extent of decline of our birds is well documented in the latest Bird Atlas of New Zealand comparing the spread of each species in the 1970s compared with the 2000. It is a sorry story of on-going decline and retraction.
An iconic example is our kiwi. Our most numerous species is the brown kiwi that once numbered in the millions. It is down to numbers of about 25,000 and declining by three per cent per year. Without intervention, kiwi will not exist in the wild for our grandchildren.
There was a time when hunting and deforestation was the primary reason for the decline of these native birds. These birds are now all protected and the impact of hunting is negligible. Nor is deforestation a substantive issue today. The area of indigenous forest in New Zealand has actually increased slightly since 2000.
The cause of on-going decline and the risk of extinction comes from predator pests. Pest enemy number one is the rat, number two is the stoat and number three is the possum.
Here’s an infrared recording of these predators at work. The female fantail escapes and the rat bites the skull of the first chick. Remember, this is all at night. He discovers a second and after a short scuffle, kills this as well and opts to use him for the takeaway menu for his offspring.
This next recording is a stoat attacking the nest of the endangered rock wren. It enters the underground nest, casually killing and removing the chick to take home for the pantry. Stoat dens have been found with dozens of native birds
And for those who think the possum is a herbivore, this third night recording shows a raid on a nest and the possum killing a newly hatched chick and egg – a routine that will play out thousands of times each night.
Landcare ecologists estimate that rats, stoats and possums kill 25 million native birds a year. That is an incredible number which puts into perspective the true scale of the threat these pests pose to our environment. Take the Rena ship grounding and sinking in 2011, noted as New Zealand’s worst environment disaster. About 2000 birds were found dead. So the damage caused by rats, stoats and possums is like having a Rena disaster every single hour.
A comparison with current conservation controversies is also informative. The Bathurst mine is expected over 10 years to displace about a dozen birds – about two pairs of great spotted kiwi and some rifleman. Our rats, stoats and possums are wiping out that number every few seconds. The Green Party are pitching the Fiordland Experience proposal as a choice between the monorail and the mohua. My science advice is that the monorail will pose negligible risk to the survival of the mohua, but that with the lack of control on rats, stoats and possums in the Snowden Forest, these cute birds will be gone within a generation. This is not to signal what decision I might make on the monorail but to point out that in these controversies over our native birds, we keep forgetting the elephant in the room.
I have mentioned that this predator problem for our birds is particularly urgent because of this year’s beech mast. Let me explain.
A beech mast is the irregular seeding of our millions of hectares of beech trees. Large and widespread beech masts occur only once in every 10 to 15 years, with smaller, localised seeding at other times. The last occurred in 2000. Forest ecologists believe that when temperatures vary between successive years by more than one degree Celsius, a beech mast is triggered. This occurred between 2012 and 2013, and observations of beech flowering throughout the North and South Island in October and November support the prediction that this summer will produce a very large seed fall.
About a million tonnes of beech seed will drop this autumn triggering a plague of mice and rats of biblical proportions. We expect rat numbers to grow from less than one to more than 10 a hectare. So, we expect the rat population in our forests to explode by about 30 million by spring.
It is not particularly convenient that this is occurring at election time but these forest mast events are no more respectful of electoral timetables than earthquakes or cyclones. I am sure our political commentators will find the irony in the rats all coming out at election time!
You might be amazed, as I was, about how fast these rat populations grow. In these sorts of ideal conditions, a rat can produce a litter of 10 offspring every six weeks. A single rat in March could theoretically produce 100,000 offspring by October.
The abundance of these rodents produces a wave of an even more deadly threat to our native birds – the stoats. These animals have ecologically developed as natural born killers. And they have a particularly unsavoury breeding cycle. The male stoat mates with his daughters before their eyes open. These young females leave the den carrying about a dozen offspring that then develop when the food conditions are right. So following the wave of millions of rats, we get tens of thousands of stoats.
This cycle turns really nasty in spring when the beech seeds germinate and this food source dries up. The starving rat population then turns on our native birds, their eggs and their vulnerable young offspring. As the rodents die off, the hordes of stoats then also turn on our native birds.
The road to extinction looks like this. Every 15 years or so, the bird population takes an awful hit from the pest plague following a beech mast. In the years that follow, the birds still face predation but just maintain their numbers. Along comes another beech mast and the population drops further. It doesn’t take long before this cycle results in extinction.
A good example was the mohua or the yellowhead population in the Marlborough Sounds. A remnant population of these birds existed through the 1990s when I was previously Conservation Minister. I remember climbing Mt Stokes and observing the attempts at predator trapping when DOC thought it was holding the numbers. An aerial 1080 drop was considered in 2000 during the last major beech mast but was thought too controversial. The birds were subsequently wiped out.
The mohua, once common throughout the South Island, and which features on our $100 note, is now down to just 5000 birds in a few pockets of beech forest in Canterbury and Southland. I am advised that this year’s beech mast is likely to wipe out another 3500 birds, or two thirds of their population. The next beech mast after that is expected to finish them off here too. An additional worry is that beech masts particularly hammer the nesting female birds. We’ve got remnant populations of birds in areas where more than 90 per cent of the survivors are male, making it so much more difficult for any recovery.
This same story of the mohua can be told of our kakariki or orange fronted parakeet. Its numbers are now down to only about 300 birds in the Hawdon, Poulter and Hurunui Valleys.
And this brings me to the nub of this speech. What can we do to protect these birds from this plague of predators?
We can look to the experience in the Dart Valley in the Fiordland National Park where during the local beech mast in 2006, some areas had pest control with aerial 1080 and others did not. Only 10 per cent of the mohua survived
the beech mast where there was no pest control. In contrast, 80 per cent survived when 1080 was used to knock down the rat and stoat populations.
The same sort of success has been achieved with kiwi in the Tongariro National Park. Measuring rat and stoat numbers is a difficult art but is done by placing detection tunnels in the forest. In August 2006, the aerial 1080 control saw the proportion of tunnels with rats plummet from 70 per cent to one per cent and the number of stoats from 19 per cent to zero and the benefits to kiwi chicks was enormous. In 2005/06, only 27 per cent made it to six months old. The following season after the control operation, 69 per cent of chicks made it past six months.
We have had the same sort of success with kea in South Westland at Okarito in 2011 and 2012. In the area that was treated with aerial 1080, kea had an average 80 per cent nesting success rate over the two years. By comparison, in the nearby adjacent area, kea nesting success averaged only 20 per cent. To put it another way, kea produced four times as many chicks or 80 new birds over two years in the area in which rats and stoats were controlled with 1080.
I could go on all night with the countless examples of the data showing the benefits to our native species from aerial 1080 operations. But let me turn to systematically deal with the half dozen arguments put forward by the opponents of 1080 use.
Their first claim is that 1080 kills kiwi. Not true. Since 1990, 430 kiwi have been individually monitored during aerial 1080 operations with radio tracking equipment. None have ever died as a result of 1080 poisoning.
It is true that some kea have died. Of 150 birds directly monitored, 20 or 12 per cent have died. In every area, the improved nesting success more than offset these losses. A new baiting protocol was put in place in 2010 that used less palatable baits. DOC now avoids using baits in open spaces above the forest edge. A kea repellent is also being developed.
The second claim is that 1080 poisons our waterways. Not true. The facts are that 1080 breaks down very quickly when exposed to water. Five hundred water samples have been taken from 1080 aerial operations over the past five years. No trace of 1080 has been found in any of the samples taken from drinking water catchments. Only two per cent of other samples had any detectable level and all were less than one tenth of the tolerable exposure limit of 3.5ppb. To put this in perspective, 1080 naturally occurs in your everyday cup of tea at levels above 10ppb.
The third claim is that 1080 is permanently poisoning our paradise. Not true. 1080 is biodegradable, unlike alternatives. The active ingredient in 1080 occurs naturally in many plants found in Australia, South America and Africa. These plants produced the poison as an evolutionary defence against browsing animals. It is possible that our own plants would have evolved to produce 1080 in their leaves as a natural defence had mammal grazers like possums got here naturally. New Zealand uses 3500 tonnes of pesticide each year and 1080 is less than one thousandth of this total.
The fourth claim is that 1080 kills domestic animals like dogs. The Parliamentary Commissioner’s report noted eight cases in four years of dogs being accidentally poisoned. More dogs are killed by other rat and slug poisons. Of course nobody wants their pet or working dog to die. Great care needs to be taken to ensure 1080 is dropped in the right places, and that use is clearly notified. Far more dogs are killed in vehicle accidents but we are not proposing a moratorium on cars and trucks.
The fifth claim I hear is that we would provide more jobs in rural New Zealand from trapping or a bounty. Aerial 1080 costs about $17 per hectare; running traps just for possums is at least three times more expensive. And that only covers the cost of trapping possums – it doesn’t deal with the rats or the stoats. We don’t build rural roads with picks, shovels and wheel barrows to provide rural jobs – we use the most efficient technology. Trapping is not a realistic option in rugged terrain or for responding quickly to mast events. Bounties can be successful with pests where there are only a few left, but with these three pests being so common it would never get numbers down to a level to protect our birds or stop the spread of Tb.
The sixth claim of opponents is that people who eat animals, fish or plants contaminated with 1080 risk death. Not true. For this to happen, an adult would need to eat in one meal either nine tonnes of puha or two tonnes of watercress; or five tonnes of eel, or 100 kilograms of venison from a poisoned deer or 30 kilograms of contaminated koura tails. It is just not a realistic risk.
The debate over 1080 has shifted significantly during the past few years in response to substantive investigations, significant improvements in its use and the failure to find any real alternative despite spending tens of millions of dollars.
ERMA, now called the Environment Protection Authority, did a huge reassessment of aerially applied 1080 in 2007. It heard all the arguments from opponents but rejected a ban. It tightened conditions of use, monitoring and reporting.
It produced its first five-year review last month. This showed compliance with the tougher rules had dramatically improved. It’s significant that the annual number of 1080 complaints has dropped from 34 to 10, reflecting the better practise and wider acceptance of the need for its use.
The game-changer in the debate has been from the statutorily independent Parliamentary Commissioner for the Environment.
Dr Jan Wright started off as a bit of a sceptic but the 2011 report and 2013 update strongly calls for the increased use of 1080 for the very reasons I have outlined in this speech.
This robust debate over 1080 during the past two decades has helped drive considerable improvements in the way the poison is used. Pre-feeding with non-toxic bait has proven to be very effective in improving the uptake by target pests. Big gains have been made in minimising by-kill by ensuring there are no crumbs of poisoned bait attractive to birds. Repellents have been developed that can be added to protect deer in popular hunting areas. The switch from fixed-wing aircraft to helicopters and the use of GPS technology has enabled far more accurate and consistent laying of bait. The poison bait application rates have been consequently reduced from 30 kilograms to as low as one kilogram per hectare.
The last change is the realisation that there is no quick fix that is going to easily replace 1080. Big money was spent on looking at potential auto-immunisation technologies that would break possums breeding cycle but it was dropped in 2010 for lack of progress. We’ve also put a lot of money into developing new poison technologies and new multi-kill traps. The new poisons only target a single pest. The new trap technologies are useful to complement 1080 but they are no real substitute.
This speech has focused on the ecological benefits from use of 1080 but I must also make mention of how critical it has been in reducing the incidences of Tb in our stock. We have around $16 billion of exports off the backs of our beef, dairy and deer herds. We were given a tough reminder last year of how sensitive our international markets are to food safety during the baby formula botulism scare. Food safety is even more important for market access than environmental integrity. The 90 per cent reduction in Tb positive herds achieved by the Animal Health Board, now Tb Free New Zealand, would not have been possible without the use of aerial 1080.
DOC last year, at my request following the PCE’s critical report, started work on a review of its pest control programme. In November ecologists observed the unfolding beech mast. This work has produced a new plan – ‘Battle for Our Birds’ – which I am unveiling tonight.
The programme is all about improved survival of 12 key species through improved pest control. The great spotted, brown and tokoeka kiwi, the kaka, kea and whio or blue duck, mohua, or yellowhead, kakariki, or orange fronted parakeet and rock wren, the long- and short-tailed bats and giant snails.
These are the target at-risk species but this programme will also save millions of birds like fantails, robins, tui, kereru, rifleman, bellbirds, tomtits and warblers. Also to benefit will be reptiles like geckos, insects like weta, trees like rata and plants like mistletoe.
This new programme is all about controlling rats, stoats and possums in the areas these 12 at risk species live. It involves about 500,000 hectares of additional pest control this calendar year to respond to that beech mast. In addition to this, DOC will extend 1080 use by 50,000 hectares a year during the next five years.
To give a sense of scale, this more than doubles control operations for these pests on our public conservation land from five per cent last year to 12 per cent.
This programme does not mean a record use of 1080 poison. This is because of much reduced application rates where we are using less than 10 per cent of the poison bait previously used. Nor is the programme just about aerial 1080. In areas where it makes sense it will be complemented by ground control techniques like trapping and other poisons.
The bulk of the new forests being protected are in the South Island - the Catlins and the Dart in Otago; the Waitutu and Hollyford in Fiordland; the Hawdon, Poulter and Hurunui in Canterbury; the Landsborough, Makarora and Mokihinui Forests on the West Coast; the Heaphy, Wangapeka and Cobb forest areas in the Kahurangi National Park as well as the Abel Tasman and Pelorus in our own area.
The five areas in the North Island to receive protection this year are the Pouiatoa forest in Taranaki, parts of the Whanganui and Tongariro National Parks and the Pirongia and Awaroa forests in the Waikato.
There is much work to be done in the months ahead implementing this programme. DOC needs to engage with affected communities, explaining what we are doing and why. They also need to monitor the beech mast and resulting plague of rats and stoats to refine the area, timing and the right mix of pest control tools to maximise the benefit for our native species. This ‘Battle for Our Birds’ is going to cost about $21 million over the next five years, out of DOC’s annual $335 million budget.
I know there are people, regardless of the evidence, who will oppose these pest control operations. As I said at the beginning, evidence-based science must trump prejudice. This is about the survival of the very species that define our country.
There is strong support from well-respected New Zealand institutions for the science behind 1080. As well as the PCE and the EPA is the New Zealand Conservation Authority, the Royal Forest and Bird Protection Society, Federated Farmers, the Federated Mountain Clubs, Landcare Research and Lincoln University. This month’s Wilderness magazine has a powerful article titled ‘1080; The Truth,’ which draws similar conclusions. There is growing momentum.
Let me conclude. New Zealand’s number one conservation challenge is ensuring the survival of our native species. We can’t let the song of our forest birds be lost except for a hollow echo on Morning Report.
The problem is particularly urgent this year with a widespread beech mast and the inevitable plague of rats and stoats. We need to up our pest control to give our birds a fair go.
This ‘Battle for Our Birds’ programme is the largest-ever species protection initiative. It’s about winning in our forests but also winning over New Zealanders’ hearts and minds. We need to back our kiwi, our kaka and our kea over rats, stoats and possums. It’s a war I am determined we will win.
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