Here in Gibbston we are trying, in a somewhat futile fashion, to eliminate rabbits on our property. Rabbits are a major pest in much of New Zealand; they eat pretty much anything at their own height, which includes all the grasses and trees that one might want to grow. Consequently, we have to encase everything we plant in two layers of rabbit protection; if the wind comes along then then one night of a lost cage can result in plant decimation.
We started our rabbit elimination attempts by hiring people to shoot rabbits. This was very costly as they all seemed to need to drive long distances to get here, and charge us for it, whereupon they managed to shoot 6 rabbits over the course of a few hours and charge us plenty more. At least they never managed to shoot the cat. Shooting the odd rabbit every now and then doesn’t pan out as a control strategy for a population with exponential growth. How do you beat an animal that starts having babies at 3 months old, and can have 6-10 babies around 6 times a year?
We have adapted our strategy over time, as our initial approach clearly was not working. At great expense, we rabbit fenced the entire property and check the boundaries at least once a year for tunnels underneath. Rabbit fencing is great if you don’t start with any rabbits on the inside, unfortunately that wasn’t the case. The fence significantly reduced the numbers of rabbits travelling into or through our property and eating plants, but as the rabbits on the inside started to breed, the piles of rabbit poo and denuded plants rapidly increased.
Next we started using rabbit poison. This is both expensive and time consuming and I don’t like to think about the rabbits crawling off to die in their burrows. We trialled spreading bait stations around our property but six hectares is large and contains a lot of rabbits. Our current modus operandi is to concentrate 10 bait stations in a small area around our house. Once the bait stops getting taken and the poo stops being deposited (as you can see we have metrics to determine success) we will be able to expand outwards. Here’s hoping this experiment is successful!
Rabbits and COVID-19 have plenty in common, as you can tell from my description. They both increase exponentially. Being able to ring fence your island to new arrivals puts you way ahead of the game, as opposed to being a country with borders you have to police. You need to take an experimental approach using techniques proven elsewhere (border quarantining, self-isolation of ill people, contact tracing, testing of people for the disease), and modify that approach over time in response to success or failure in your own specific location. You need to have metrics to determine whether what you are achieving is success or failure and monitor them closely (in the case of COVID-19, testing provides those metrics). I believe that one also needs to be prepared to wear critique of your approach, in the interests of achieving the best outcome, as well as bringing others along with you in your efforts (and ensuring they don’t sabotage your approaches).
In the interests of open critique, I was disappointed yesterday by some of the vitriol in the media, regarding the challenge posed by a group of New Zealand university academics to the current ‘status quo’ in terms of the best way to control COVID-19, post the Level 4 lockdown. One reaction, played up by the media, appeared to be “eliminate, eliminate”, rather than any considered response. The appropriate reaction, taken by Siouxsie Wiles in the Spinoff and Newsroom, is to consider the opposing view, examine the points it makes and debate whether they are valid. The inappropriate response is to slam and personally attack the questioners. My ‘favourite’ critique in that vein, was that the lead commentator of the contrarian group “isn’t even a Professor”. While I am very happy that New Zealand wants to be science led in our approach to COVID-19 (as opposed to, say, the USA), adulation of professors as pinnacles of knowledge should not be universal and unquestioning. University professors are as fallible as anyone (I work with many). They can have very narrow areas of specialty, outside of which they are not very knowledgable at all.
It is in all our best interests that questioning continually takes place, is considered appropriately, and that people refrain from ad hominem attack, in place of argument. If you want an excellent example of ad hominem attack, you only need to look at a few clips of Trump’s speeches. Yesterday Trump told Paula Reid of CBS ‘You know you’re a fake!’, when she pointed out that he had not used the time prior to explosion of COVID-19 in the USA to prepare; there were no arguments he could marshal. It would be a great shame if the New Zealand populace or media see that as good strategy.
A final thought on ‘eliminate’, is that the community need more clarity around what is meant by ‘eliminate COVID-19′ and whether it is achievable. We would like to eliminate rabbits from our property but, as New Zealand predator control exercises have found, getting the last few rabbits will be as time consuming and expensive as getting the initial 90% of them. The likely scenario is that we will manage the numbers down, over time they will increase, then we will manage them back down again. This is similar to a ‘mitigate’ scenario for COVID-19, which countries with porous borders (by choice or circumstance) are having to employ – they can’t shut the virus out, they know they have to live with it. The implications of ‘mitigate’ are pretty unpleasant – 12 months of cyclic lockdowns and released restrictions sound inherently difficult for both social and economic activities.
New Zealand is actively choosing to head down the ‘elimination’ pathway for COVID-19; the fundamental premise of the contrarian group was that they don’t believe complete elimination is feasible. We are being ‘sold’ elimination as the scenario which will allow us to have ‘normal’ lives until a vaccine is available. Virus elimination remains unproven in any other country’s action research experiment, although everyone agrees that New Zealand has a fair shot at it. Can we eliminate all cases of COVID-19, or get them to such a low level that we can rapidly track and isolate all people contacted by the few remaining cases that ‘pop up’? How will that work if up to 60% of people with COVID-19, or even 80% as suggested recently, can be asymptomatic? We still don’t know how well those who are asymptomatic transfer the virus and we can’t identify them until an antibody test is widely available and used. Unless someone provides a crystal ball or a time travel machine the answer would seem to be, we need to stick with the experimental ride while the economic hounds’ cries rise in volume.