Paul Daly

A virus to cure a plague

It looks endearing but the rabbit’s voracious appetite means that, in some parts of the country, it is more destructive than any other intro­duced pest. Its resistance to environmental stress and its remarkable reproductive capacity makes it almost impossible to control.

Written by       Photographed by Arno Gasteiger

“How do we know that if we talk to you we won’t get prosecuted?”

I shift in my seat while the three men give me a level stare. We’re sitting in the Tarras Community Hall tearoom, me at the front and them on the near-empty row of chairs. “They’re the staunchest people I’ve come across,” a Ministry of Agriculture and Forestry detective had warned me earlier in the day. “I wish you luck.”

It’s been almost 11 years since rabbit calicivirus disease (RCD) was first discovered on a Central Otago farm, in August 1997. Known as New Zealand’s biggest intentional biosecurity breach, it was a huge blow to the integrity of our nation’s border officials. Not only had a highly infectious agent been smuggled into the country, it appeared that the crime had been committed by a group of New Zealand farmers. While military-style roadblocks barred major roads in the lower South Island, and MAF frantically waved decontamination wands over piles of dead rabbits, farmers seemed to look on with quiet satisfaction. Most pleaded ignorance, but a few admitted to liberating the virus on their farms. They posed for the media alongside kitchen whizzes in which, they claimed, they’d mixed their deadly viral cocktails.

It looks endearing but the rabbit’s ferocious appetite means that, in some parts of the country, it is more destructive than any other introduced pest. Its resistance to environmental stress and its remarkable reproductive capacity makes it almost impossible to control.
It looks endearing but the rabbit’s ferocious appetite means that, in some parts of the country, it is more destructive than any other introduced pest. Its resistance to environmental stress and its remarkable reproductive capacity makes it almost impossible to control.

For a whole week calicivirus made front-page news. But then Princess Diana died, and for most so did the story of New Zealand’s biggest rural conspiracy.

More than a decade has passed, and I assured the men in front of me that I had talked to the head of Biosecurity New Zealand and there would not be any legal ramifications.

Semi-retired farmer Donald Young was the first to agree to talk. It was on the 1100 ha Te Oma fine wool merino station, owned with his wife, Sally, that the virus was initially discovered.

“It began with a phone call,” explains Sally.

“Donald was away at a Federated Farmers meeting. We’d just heard that the Ministry of Agriculture had denied the official application to introduce RCD. Flippantly I asked the caller if he had some virus for us. He said he might have.”

[Chapter Break]

Rabbits don’t make very good villains—the floppy ears, twitching nose, the soft, fluffy fur. However, in some parts of New Zealand, particularly on the semi-arid, eastern side of the country—from Hawke’s Bay in the north to near the bottom of the South Island—they do more damage than any other introduced agricultural pest, including possums.

The problem is their numbers. No accurate figures exist, but some say that 60 million would be conservative. Many areas of the Mackenzie Basin and Central Otago, where golden tussocks once adorned the hills, have been reduced to a barren wasteland, an almost lunar landscape that supports only patches of scab weed and stonecrop. Rabbit damage covers thousands of hectares of New Zealand back country, which can be seen from a satellite 800 km above the Earth.

They are known for their legendary ability to breed like, well, rabbits. As Otago Regional Council rabbit compliance officer Don Robson explained, the first trick up a rabbit’s sleeve is a flexible family planning schedule, which can change depending on the conditions. “The doe usually gives birth to five or six kittens, but when food is plentiful, a litter size of eight is not uncommon.”

And that’s not the half of it. “Most females are impregnated again within 12 hours of giving birth.” To top it all off, rabbits retain the innocence of youth for only a short time, becoming sexually mature at three to four months. In an ideal scenario, one pair of adult rabbits and their young can multiply to almost one million in just one year. Robson is quick to point out that conditions are never ideal—the vulnerable kittens are sensitive to various diseases such as coccidiosis, drowning in the breeding burrow, as well as becoming dinner for a number of introduced predators. Nonetheless, the reproduction rates of New Zealand rabbits are among the highest in the world.

Rabbits have a ferocious appetite—12 to 15 will consume as much as one ewe—but worse is the fact that rabbits actively maintain the barren conditions they create, shunning long grass in favour of sweet, succulent new shoots that they keep trimmed to ground level with their razor-sharp incisors. When it comes to persevering in this kind of environment, rabbits have an advantage—they re-ingest their faeces, which are passed as soft, membrane-covered pellets the first time round. Farmers say it just shows how disgusting the “feral beasts” are, but it’s actually an efficient way of maximising the energy derived from their food—the bacteria in the caecum (a special pouch in the gut, of which the human appendix is a redundant vestige), digest the hard cellulose that other mammals like us can’t deal with.

Deprive a rabbit of food, however, and it really starts to prove its resilience. When food is scarce, the female rabbit can actually reabsorb her foetuses. Pest control manager Peter Preston has also witnessed a number of extreme behavioural responses: rabbits climbing into willow trees to strip off leaves and bark at the height of summer, reducing gorse bushes to topiary on the banks of the Clutha River, chewing on the bark of matagouri while the ground is covered in knee-deep snow, and even jumping one-metre-high rabbit-proof fencing to get to better feeding grounds. Up the Kawarau Gorge towards Queenstown, Preston shows me a row of tanalised fence posts cleaved by rabbits in almost beaver-like fashion, the remains of a last-ditch attempt to gain nourishing salts (never mind the arsenic) in an otherwise completely denuded paddock.

[Chapter Break]

Rabbit calicivirus disease was first noticed by scientists in 1984, when farmed rabbits in China started dying in large numbers. The Chinese were adamant that it didn’t originate there, arguing that it came aboard a shipment of Angora rabbits from East Germany (a claim that has recently been supported by the discovery of a non-pathogenic rabbit calicivirus in Europe). Through trade, the virus hitchhiked back to Western Europe, then North Africa and some parts of North America, where it wreaked havoc on wild and often protected European rabbit populations. While overseas scientists scrambled to find a vaccine to prevent local rabbit extinctions, the Australian and New Zealand governments were rubbing their hands together; this was the bio-control agent they’d been looking for. In 1991, they began a joint research programme that was to last six years.

After being purchased in Czechoslovakia, the virus was studied in an animal containment facility at Geelong, Australia. “For RCD to be approved for release, we first had to establish that it wouldn’t infect non-target species,” explains Brian Cooke, the world’s foremost calicivirus expert.

For farmers like John Perriam of Bendigo Station, near Alexandra, rabbits were costing $120,000 a year in poisoning and shooting—and the arrival of calicivirus was most welcome.
For farmers like John Perriam of Bendigo Station, near Alexandra, rabbits were costing $120,000 a year in poisoning and shooting—and the arrival of calicivirus was most welcome.

The next step was to test the virus’s effectiveness in controlling wild rabbit populations. Field trials began in 1995 on Wardang Island off South Australia. Security was tight; double high fences enclosed radio-collared rabbits. Yet within six months calicivirus had somehow crossed 5 km of water to the mainland. While it had been assumed the virus spread through rabbit-to-rabbit contact, Cooke thinks it was most likely spread by flies.

Once liberated, the virus moved 100 km a day, no doubt with help from rural supporters. Within 18 months, it had spread over two-thirds of Australia, wiping out rabbits en masse.

This wasn’t lost on the New Zealand farming community. Encouraged by the government, an applicant group was quickly put together, consisting not only of the farmers, but also several trusts and organisations, including five regional councils. For calicivirus supporters, all the signs pointed to one conclusion: the virus would be effective as a bio-control agent in New Zealand.

But DOC and the Royal Forest and Bird Protection Society were concerned about prey-switching (such as mustelids and hawks relying more on native fauna in the absence of rabbits), while others argued that the effects would not be much more dramatic than the boom-bust of large-scale poisoning. Particularly outspoken was California-based expert Alvin Smith, who had spent most of his career studying the San Miguel sea lion virus, also a calicivirus. He highlighted the fact that out of the five calicivirus groups known to man, four infect and cause disease in humans and three are known to jump species. The corresponding media debates were also starting to create unease in the wider public.

Another round of consultation was called for, with responsibility for the final decision falling to just one person. “The pressure was enormous,” says Peter O’Hara, a former deputy director-general at the Ministry of Agriculture and Forestry. “I visited some of the more rabbit-prone areas. What I saw shocked me: the rabbits were literally eating up the land, land on which families were depending for their livelihood.” He describes his inner turmoil, for weeks debating with himself. “I knew that the farmers had a genuine need for the virus, but I couldn’t let emotions rule my decision.” In the end, his concern was that it wouldn’t work in New Zealand’s temperate climate, and concluded that the risks of introducing a foreign organism were not justified. On the second of July 1997, the government announced that calicivirus would not be introduced into New Zealand at that time.

“I was very unhappy,” says the then Minister of Agriculture, Lockwood Smith. “My words were probably not even that polite as I discussed with him [O’Hara] the likelihood that farmers would now introduce the virus illegally.” He was unaware that, even before the decision was made, farmers had already dodged airport blacklists and were about to do just that.

[Chapter Break]

“I’d never eat a rabbit,” says Alistair Campbell, owner of Earnscleugh Station. “To me they’re like rats. I hate them. They’re vermin.” Campbell lives in a brick manor set on 18,000 picturesque hectares of tor-studded hills near Alexandra. He places a row of photographs on the table to show me the extent of rabbit damage when he took over the station in 1981. “The rabbits were merciless. They ate everything—the grass, the native vegetation, they even climbed to the tops of bushes and grazed them down to the roots. There was nothing left for the sheep.” The pictures show little more than toothbrush stubbles of tussock and bare soil.

Campbell has declared war on rabbits but also notes that on his station, it was actually a farmer who introduced them, wanting some familiar game to shoot on Sunday afternoons. The gentleman, William Fraser, one of the first owners of Earnscleugh, released several breeding pairs into the hills in the 1860s, the first rabbits in Central Otago. But go back another step, to how the ancestors of Fraser’s rabbits got to New Zealand, and the details get fuzzy. Captain Cook is said to have released a pair in the Marlborough Sounds in 1777, and whalers most likely added them to their free-ranging larder.

However, Evan Tosh, a Dunedin fur-dealer who has recently completed a masters degree in the history of the rabbit, thinks that these early introductions were most likely of fancy breeds, which would have easily perished in the wild. “The rabbit that does so well in New Zealand is Oryctolagus cuniculus, the feral European rabbit that originated in Spain. It was brought out from England, possibly via Australia.”

Rabbit hunter Steve Bell takes aim. Dispatching rabbits is now a dying art, but a little over a century ago trapping rabbits was the basis of a booming industry, called the ‘second gold rush’ in some areas.
Rabbit hunter Steve Bell takes aim. Dispatching rabbits is now a dying art, but a little over a century ago trapping rabbits was the basis of a booming industry, called the ‘second gold rush’ in some areas.

What is certain is that by the 1860s, naturalised rabbit populations were popping up from Carterton to Bluff, their spread encouraged by various high-standing members of society as well as early versions of A&P shows. That most indefatigable of institutions, the Acclimatisation Society, also decided to lend a helping hand. In 1865, the Otago branch released at least 60 rabbits in locations unrecorded, and in 1866 the Canterbury constituency proudly reported that “an enclosure has been set apart for the silver-grey rabbits presented by Sir G. Grey, which increased to a great extent, and have been distributed to members far and near”.

This was despite warnings that in various tracts of rural Britain rabbits were eating some families out of house and home. It soon became obvious that the same thing was about to happen in parts of New Zealand. Eyewitnesses of the time reported that the ferocity of the onslaught in some areas was terrifying, the rabbits overrunning thousands of hectares in periods of less than five years. On Earnscleugh Station, William Fraser, who had protected his first rabbits with zealous fervour to the point of prosecuting a man for poaching a couple of coneys, was finally run off the land by his pets in the mid 1890s. Even the Acclimatisation Society that had so recently been patting itself on the back was now distancing itself, claiming that the introduction of rabbits “cannot be laid to the charge of this society”.

As the rabbits multiplied, they spread into neighbouring provinces, their advance aided by the very people who cursed them most. Farmers were opening up the high country through sheep grazing and large-scale burn-offs, replacing tussocks with introduced grasses, the shoots of which are caviar to rabbits. With plenty of food and virtually no natural predators, a terrifying plague was being unleashed. The areas most affected were those with an amiably dry climate—parts of Hawke’s Bay and the dune country around Wanganui in the North Island, Marlborough’s Awatere Valley and inland Kaikoura, and large tracts of the Mackenzie Basin and Central Otago in the South Island.

By the time that 19th century landholders were beginning to comprehend just how much trouble they had made for themselves, it was too late. “This country is not worth saving—let the rabbit have it,” was the alleged reaction of a North Island member of the early Rabbit Destruction Council when he saw the ravaged hills of Central Otago.

[Chapter Break]

Fast forward to 1997, and Donald Young had reached a decision. “For years we’d been forced to stand by and watch as rabbits denuded our paddocks and turned them into a dustbowl. It was a simple choice: get calici or go bankrupt.” He waited until nightfall, then made the two-hour trip to a friend’s place. “I wasn’t scared, just very, very excited.” After making deliveries to a couple of other farmers on the way home, he placed his own few precious milli-litres of crudely camouflaged virus in the fridge.

Sixty kilometres down the road, Bruce Jolly, who farms in the Ardgour Valley, south of Lindis Pass, had come to the same conclusion. “I knew I was doing something wrong by committing an illegal activity—here was a banned organism and I was attempting to spread it. But as far as my environmental conscience and survival as a farmer went, I felt it was something that had to be done.”

“We were forced into a no-win situation,” says Pete Davis, who owns the multimillion-dollar hill country that makes up Shirlmar Station. “We had to do this, or some of us would have gone out of farming. In fact, one or two of my friends would have gone out of farming the next year if we hadn’t brought in the virus.”

Some farming wives were kept in the dark about the viral experiments happening in their backyards. But Sally Young was adamant that she and Donald were in this together, and she insisted on helping to spread the virus. There was, however, one snag: they weren’t sure how to go about it.

“We’d been following the research on RCD quite closely—we’d even put our own money towards it through the High Country Trustees. So we knew that the recommended method was to infect rabbits, release them back into the wild and let the virus spread naturally.”

But this would take time, which was something the Youngs didn’t have. Success depended on infecting as many rabbits as possible before the virus was discovered. Instead, they turned their viral cocktail into a biocide, injecting it into live crops in the field, lacing carrots and oats, as well as stuffing rabbit carcasses and viscera down burrows. “Although we were convinced that what we were doing was safe,” Sally Young says, “there was still this feeling that we were really stepping into the unknown.”

In the 1930s Petone school boys earned money hanging out rabbit skins for export.
In the 1930s Petone school boys earned money hanging out rabbit skins for export.

For the virus to be effective on a large scale, farmers had to make more. Calicivirus can’t be cultured, so the only option was to breed it in live rabbits. “If you’ve ever tried catching a rabbit, it’s no easy task,” laughs Pete Davis. After a few failed attempts at running them down, Davis resorted to making the eight-hour round trip to Dunedin to buy nylon netting for patching the holes in his rabbit fence. “That night we tore across the paddocks, firing shots, pushing the little buggers against the fence—and caught six rabbits!”

Woolbales, old chicken coops, even horse-floats, were converted into makeshift laboratories where the ill-fated rabbits were kept. “It was the most risky part of our operation,” says Bruce Jolly. “There’s just no other reason why a farmer would be keeping feral rabbits.”

Back at Te Oma, Donald Young demonstrates how he injected his long-eared subjects with the virus. When I ask him about protective gear, he laughs. “No, we were absolutely convinced that the virus wouldn’t do us any harm.” It appears few farmers were concerned for their personal health; much later, 17 admitted to accidentally sticking themselves with virus-laden needles.

It took 48 hours for the rabbits to die. The most infective organs were believed to be the liver, spleen and kidneys (some of which take on a characteristic speckled appearance post-infection), so these were extracted and reduced to liquid. As if hosting a sinister cooking show, Young pulls out an old kitchen whiz, the same one he used 10 years ago, and turns it on.

The resulting pulp was too thick to suck into a syringe. “I remembered back to the days of playing at laboratories as a schoolboy,” he explains as he takes a couple of specimen pottles out of his sheep-worm-testing FecPack, “so I decided to make a centrifuge.” He fills the containers with viral cocktail, places them in a short length of alcathene pipe, and bolts the contraption to the woolshed grinder. This is number-8-fencing-wire technology at its best. Well, almost. “The first one stood proud, and wham! splattered the walls of the shed,” he recounts, throwing his arms up in the air with the enthusiasm of a child at Christmas. “But Mark II worked brilliantly.” He likens the consistency of the resulting liquid to “a fine Central Otago pinot noir”.

[Chapter Break]

The first Rabbit Nuisance Act was introduced in 1876. But in their eagerness to control the pest, early conservationists sometimes gave little thought to potential consequences. From 1884 onwards, thousands of ferrets, stoats and weasels were introduced as natural predators specifically for controlling rabbits; many of these disappeared straight into the bush and tussock lands, where they found naive, native birds and lizards much more to their liking. Another natural predator, Felis cattus—the domestic cat—was carted by the thousands into rabbit-prone areas such as Molesworth Station in Marlborough. Selling cats as rabbit-exterminators was such a lucrative industry that large numbers of household moggies started disappearing under suspicious circumstances. But it soon became clear that they, too, were just barely scratching the surface of the problem.

In an attempt to contain the spread of what became known as “the Evil”, large-scale rabbit-proof barrier fences were put up in some of the more prone localities. In 1882, a 65 km mesh fence was erected in an attempt to protect the Hawke’s Bay area, followed by three others to prevent spread between provinces, the longest stretching 130 km from Kurow to Lake Tekapo in the Mackenzie Country. They all failed. “Rabbit fences are only as good as the people who maintain them,” farmer Doug Brown tells me as we walk along one of his honeycomb-mesh fences on Locharburn Station between Cromwell and Wanaka, placing rocks over rabbit holes and tunnels. “If there’s a weak spot in the fence, you can put money on it, rabbits will find it.”

As for the pioneering landholders, it soon became clear to them that to curb the rabbit explosion, they needed to launch a strategic counter-attack. So they put a price on the rabbit’s head, and trapping rabbits became the basis of a booming industry, known in some areas as the “second gold rush”.

Droves of men had flocked to rabbit-plagued lands to trap the furry critters for their skins, which they dried and stretched over wire before selling to agents. In fact, the dried skins proved such a good income that some rabbiters were eventually able to buy the block of land they were working on. As for the dried skins, they were picked up by a “rabbit cart” and transported to Dunedin, where the huge piles awaited export. “Next to Presbyterianism, I am told that hides are Dunedin’s chief religion,” a correspondent to Forest and Bird magazine wrote.

Bun Scott has been a rabbiter all his life, although these days he does it out of habit rather than for money.
Bun Scott has been a rabbiter all his life, although these days he does it out of habit rather than for money.

To get a sense of scale of the industry, between 1895 and 1900 more than 63 million rabbit skins were exported. If laid end to end, they could have formed a continuous bridge from Auckland to Honolulu.

It wasn’t just the fur that was a valuable resource—advances in preserving meat meant that rabbiters now had an additional resource to sell. Canning factories sprang up in Alexandra and Cromwell in the late 1890s and 1915 respectively, and millions of frozen carcasses were also exported.

The problem was that rabbit numbers weren’t actually going down; on some stations there were more than ever. The inspectors of the day blamed the shift in local attitudes towards the rabbit, that the former pest had become a valuable resource. They accused rabbiters of protecting their business by selectively working blocks, leaving behind sufficient “breeders” to help the population explode in time for next season’s trapping. Evan Tosh, however, doesn’t think this was the case: “Many rabbiters were also working as general farm labourers. In spring and summer they just had other things to do. Unfortunately, that’s when the next few generations of rabbits were being born.”

It was clear, however, that control methods weren’t working and it was time for something else. It came in 1938 with the introduction of the “Killer Policy”, enforced by specially formed Rabbit Boards.

Run by local committees of landholders, the boards placed the problem as well as the solution into the hands of the people most affected. They identified where rabbits had to be controlled within their regions, and charged themselves and their neighbours rates to control the pest, levies that were then subsidised dollar-for-dollar by the government. In their heyday (1960), there were 210 Rabbit Boards.

Bun Scott was in charge of the Bannockburn Rabbit Board. “Our job was to kill rabbits all year round,” he says. “Basically, we were out to get the very last rabbit.”

Professional rabbiters like Scott used almost every tactic at their disposal—smokers, fumigation with chloropicrin gas, picks, traps, shotguns, even tame ferrets—but the most effective technique was poison. The first poison of choice was strychnine, a plant-derived, bitter powder that was most commonly sweetened with icing sugar and then pasted onto carrots that were spread by hand, often into the furrows of freshly ploughed lines. Some rabbiters found an alternative, performance-enhancing use for the powder, licking tiny amounts to give them “a bit of a lift” up a steep hill—not an advisable practice since the nerve-damaging agent is cumulative and deadly. Strychnine was succeeded by more modern poisons—mainly arsenic, and jam laced with phosphorus—until the major breakthrough with the first aerial drops of sodium monofluoroacetate, more commonly known as 1080, in the mid-1950s.

Rabbits reduced thousands of hectares of the Mackenzie Basin and Central Otago, once covered in golden tussock, to a barren wasteland. Because they prefer new shoots to long grass, rabbits prevent the land they have decimated from regenerating.
Rabbits reduced thousands of hectares of the Mackenzie Basin and Central Otago, once covered in golden tussock, to a barren wasteland. Because they prefer new shoots to long grass, rabbits prevent the land they have decimated from regenerating.

More than a hundred years after their introduction, numbers started dropping dramatically. “There’s no doubt that advances such as 1080 were a huge boost,” Scott says as he throws a couple of rabbits into the truck “for dinner”.

“But I think we were successful because of the organised and systematic way in which we were working, not letting the rabbit get away on us once we had numbers down.” For the first time there was optimism. Some believed that within the decade, the rabbit could actually be exterminated. The complete devaluation of rabbit skins and carcasses in 1957 was the final coup, and for the next two decades rabbit levels were largely under control. 

But the reprieve didn’t last. In 1971, the government decided that it was spending too much money getting rid of the very few rabbits that were left, and changed the “Killer Policy” to one of control. The biggest blow came in 1981, when the government stopped the dollar-for-dollar subsidy and allocated funds to boards based on how prone their areas were to rabbits. This decision financially crippled many of the boards, and it was up to farmers to bear the full costs of rabbit control.

One such farmer was Peter (‘PL’) Anderson, who until recently ran Cloudy Peak Station in the Ardgour Valley. Cloudy Peak has a Grahame Sydney-esque beauty from a distance, but the 4000 ha of sunny rolling hills are renowned as the most rabbit-prone area in New Zealand.

Unusually, Anderson didn’t inherit his land. He left school at the age of 14, and spent the next 20 years as a station hand and a farm manager. Through hard work and a bit of luck, he and wife Jan acquired Cloudy Peak Station in 1980, the last undeveloped block in the Upper Clutha district. They knew about the land’s history of rabbit infestations, but at that time the Lindis Rabbit Board was keeping the overall numbers down to manageable levels. “Each year we paid $7000 in rates to the board, and they did a good job.”

But the following year the government announced its decision to phase out the dollar-for-dollar subsidies for rabbit control. “We had no money left, but I vowed not to let the things take hold,” says Anderson. He took part in a five-year land and rabbit management programme trial, after which he employed two permanent rabbiters, and organised regular poison operations on his land. The annual bill was around $70,000. Income from their station’s sheep didn’t cover costs, and the rabbits were keeping feed low. “If it wasn’t for my wife’s job, we would’ve gone under a long time ago.”

The Andersons were not alone. In the 1991-92 financial year, 72 per cent of properties in rabbit-stricken areas were running cash deficits. On 33 per cent of farms debt servicing exceeded 25 per cent of gross income, and 28 per cent of farms were no longer viable. Farmers were increasingly desperate to get rid of the rabbits, and increasingly willing to consider any means necessary.

[Chapter Break]

As we follow a maze of dirt tracks through Ardgour Station, Bruce Jolly brings his four-wheel-drive to an abrupt stop, drawing my attention to a gully cleaving the barren hills on our left. When the calicivirus took hold in 1997, these gullies were filled with dead rabbits. “You could smell the death long before you could see it,” he says. “I’d never dreamed of anything like this as far as rabbit control went. Even though it was death, it was a pleasing sort of death.”

Donald Young had gone one step further; his property was about to be intensively worked over by pest control officers from the Otago Regional Council. Months earlier he and his wife had scheduled a poison operation on their station and adjoining land, and they couldn’t put it off without attracting suspicion. Not wanting to be caught red-handed with the virus, but unable to bring himself to flush the precious fluid down the sink, he dribbled it on to the 10 tonnes of un-poisoned feed the regional council had sitting on his airstrip. “I didn’t really think anything would happen,” he says with a shrug. Not realising their rabbit bait was spiked, the council staff blanketed more than 1000 ha with the virus. Field adviser Peter Preston was among the first to discover the carnage two days later. “I didn’t mind that RCD was here, I was annoyed that they’d botched an expensive operation that took months to put together.”

The confirmation of the virus’s discovery almost doubled the population of Cromwell, with politicians, reporters and law enforcement officers vying for space in the town’s single hotel. MAF, joining forces with the police, locked down five farms and checked all vehicles passing in to and out of the area for rabbit material. But it soon became apparent that the situation was well beyond the government’s control.

“I did a helicopter recon of the area shortly after the discovery,” recalls the regional council’s Jeff Donaldson. “There were thousands of dead rabbits lying on the ground. When I took a group of politicians over the same spot the next day, they were gone.” The missing carcasses re-appeared a day later, this time on driveways and in trees and bushes many miles away. MAF duly closed Cromwell’s airspace, but it was too late; a good part of the lower South Island had already been liberally top-dressed with calicivirus.

In an attempt to gain local cooperation, the officials called an emergency meeting in Cromwell. “It was the most buoyant, joyful meeting I’ve been to in my farming career.” Pete Davis recounts. “When the members of Parliament asked us how the virus came in, somebody stood up and said, ‘You don’t think we’re bloody stupid, do you?’ Of course, nobody said a word.” Desperate for answers, Lockwood Smith made an unexpected ministerial announcement: in exchange for information, those who had spread the virus would be granted immunity from prosecution. Prime Minister Jim Bolger backed his decision. “It’s never right to break the law,” says Bolger, “but there are offences against the law you can understand, and this one I could understand even if it was wrong.”

Unaware its rabbit bait was spiked, the Otago Regional Council unwittingly blanketed 1000 hectares of land with calicivirus. Many regard the virus as a godsend and those involved in spreading it remain unrepentant.
Unaware its rabbit bait was spiked, the Otago Regional Council unwittingly blanketed 1000 hectares of land with calicivirus. Many regard the virus as a godsend and those involved in spreading it remain unrepentant.

Several months later the government moved to amend the Biosecurity Act to legalise the infectious agent. This infuriated many, including The New Zealand Association of Scientists which organised a conference to express members’ frustrations. “This Bill contravenes the principle that criminals should not benefit from their crimes. Inaction by Government makes it a party to the illegal actions.”

But by then the virus was widespread, and farmers were determined to make sure it was here to stay, hiding vials around their properties “as an insurance policy”. This, coupled with the absence of obvious ill effects, resulted in the virus being legalised by 1999.

“The virus was an absolute godsend,” says Sally Young. “We were able to invest the money usually spent on rabbit control on other parts of the farm, like the new tractor we bought, and for top-dressing the land.” Says Bruce Jolly: “The transformation was amazing. The grass was no longer being chewed to the ground, native plants I’d never seen before started appearing.” Councils, too, have since used the virus to good effect, releasing it on to recreation reserves and parks from Southland to Wellington and Auckland.

But it hasn’t been a silver bullet. Some areas such as the Mackenzie Basin have managed to keep their rabbit numbers relatively low, but in Central Otago they’ve made a spectacular comeback. Some point the finger at the crude application methods initially employed by farmers. “The use of the virus as a biocide exposed it to natural elements such as sunlight, which kills RCD,” says University of Otago microbiologist, Frank Griffin. “Some farmers were actually vaccinating their rabbits.” Also, the timing was not ideal. The breeding season had begun and young rabbits have a natural immunity against calicivirus.

Others place blame for the rabbit rebound on farmer complacency. “RCD provided a golden opportunity to get on top of rabbits while their numbers were low,” says Peter Preston. “A few farmers followed up with secondary control methods, but many simply put their wallets in their back pocket and expected RCD to solve all their problems.” It hasn’t: immunity levels are up to 90 per cent in some rabbit populations. This is not to say that the virus no longer works—it does—but it appears to move through populations in waves, decimating some, missing others. The reason for this selective fashion is unclear.

The mystery of who actually smuggled calicivirus into New Zealand remains unsolved. Tests confirm that the virus was sourced from a lab, but as for how it got here, there are almost as many theories as there are farmers: a vial hidden in a sock, camouflaged among toiletries, a soaked tissue in the post—the possibilities are limited only by your imagination, as detecting minute amounts of virus is virtually impossible.

As I was wrapping up my story I received an excited phone call. “They soaked the virus in a jersey, then cut it into seven squares,” the caller told me. “One of those pieces now hangs framed in a Marlborough farmhouse.” I dialled the number provided. I managed to keep the person who answered on the phone for eight and a half minutes, but the repeated response was: “I don’t know anything about rabbits or viruses.”

A decade later, farmers who spread the virus say they have no regrets. “There were absolutely no negative consequences,” says Bruce Jolly. “I would do it again.”