Experts dump on dung beetle

Grant Guilford

Dr Grant Guilford said there had not been enough duty of care around protecting New Zealand’s biosecurity in assessing the beetle’s introduction.

Leading scientists and health experts believe there are major risks if dung beetles are released in New Zealand.

The beetles are in caged field trials in Northland after approval was granted by the Environmental Risk Management Authority (ERMA) for 11 species to be imported.

ERMA has since been disbanded and the Environmental Protection Authority (EPA) has taken over its role.

Championed by Landcare, the beetles are intended to assist rapid breakdown of animal waste, help reduce fly infestations resulting from dung presence, and possibly reduce the need for drench use.

However, Dr Grant Guilford, dean of science at Auckland University, has voiced concerns over how significant the benefits of the beetle are and the robustness of ERMA’s risk assessment.

Guilford’s ability to speak openly about the beetle’s release was constrained earlier by his position on the Landcare board, the science organisation sponsoring the beetle’s release.

He resigned from the board last year, in part because of significant misgivings he had over the assessment process.

He said the last straw was Landcare’s decision to disregard a letter from the Auckland Medical Officer of Health advising of a need for better assessment of public health risks in beetle release.

The caged trials on the beetle do not include close analysis of human health risks.

Guilford’s concerns rose initially when his research staff, veterinary and medical colleagues sounded warnings on the beetles’ potential to act as carriers for a variety of diseases affecting animals and humans.

Submissions to ERMA against the beetles’ release in NZ included concerns from two of his staff.

But issues were also raised by the Auckland Council, the Auckland Regional Public Health Service, and Fonterra.

Guilford then compiled a report for EPA and Landcare highlighting the beetles’ potential as disease carriers.

The peer reviewed report contained extensive overseas research challenging ERMA’s (now EPA) view the exotic beetle’s release would not cause adverse effects on human health or safety. 

The paper highlighted beetles’ ability to carry gastrointestinal diseases of humans, livestock, dogs and wildlife. They include cryptosporidium, giardia, E.coli, campylobacter and salmonella.

“The overarching comment from those assessing the paper was ‘there is a real level of risk here and we need to do more research to quantify the risk’,” Guilford said.

Other risks included the ability of the beetle to fly long distances, giving it the potential to spread exotic or local diseases across regions, and to spread diseases by contaminating rural water supplies.

Guilford described the information ERMA had based its beetle assessment on as poor quality and too reliant on the Australian experience with the beetle.

“The application was not what we would call a good, quality piece of work. It wasn’t thorough or balanced and lacked assessment by animal or human health experts.”

He said it was wrong for Landcare staff to answer “no” to the application question asking if the beetle could cause disease, be parasitic, or be a carrier of human, animal or plant diseases.

However, Landcare chief executive Dr Richard Gordon said while many organisms, including flies and earthworms, were capable of also carrying diseases, Landcare did not believe dung beetles could transmit those diseases to people. 

He said Landcare’s beetles also had a clear preference for cattle dung, with research suggesting they would be attracted to other animals’ dung only when that was not present. A constant supply of cattle dung made that unlikely.

“Dr Guilford’s report was assessed thoroughly by EPA and was not found to substantiate concerns about the dung beetles subject to approval.”

But having spent more than 20 years at Massey’s veterinary school, Guilford said his “veterinary bones” told him there had not been enough duty of care around protecting New Zealand’s biosecurity in assessing the beetle’s introduction.

A year ago he felt concerns were being heeded, when a technical advisory group (TAG) was created to examine the concerns closer and establish beetle trials.

“It was a good, well-qualified group and they decided they needed to do cage trials on the beetles. It was late, but at least good oversight.”

Auckland Council biosecurity manager Jack Craw also confirmed misgivings his scientists had over the beetles’ release, despite providing some initial funding for the project.

“We were keen on the concept but are concerned there has not been an appropriate level of environmental audit on this.”

As a member of the advisory group, he has had no response from his queries to Landcare since trials started in early October last year.

“I think a lack of funding is a big part of it. The trials should have been done even earlier, before a hearing was carried out, given how important they (the beetles) are.”

However, Gordon said that trial’s results would be presented to the group as soon as they were available.

Gordon emphasised while no longer in containment, the beetles were contained in cages during the field trials. He said should the beetles be found to be unsuitable for field release they could be destroyed

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  • Stephen Thorpe • 2 years ago

    The questions have been answered badly on Andrew Barber's closed edit site, so I have replied on the blog under the article here:

  • Andrew Barber • 2 years ago

    Two of the questions raised below: 1. Will dung beetles increase the incidence of E. coli O157:H7 in people in NZ? 2. Will dogs in NZ be at greater risk from the nematode Spirocerca lupi? These questions have been answered on the FAQ page of the Dung Beetle Release Strategy Group website

  • Grant Guilford • 2 years ago

    Hi Alex The opposition you are hearing is to sloppy biosecurity practices that create risks to farmer livelihoods, trade and public health. It’s not opposition to dung beetles per se. All that is required for more widespread support of the dung beetle release is for prudent research to be undertaken to establish the scale of the likely benefits and the significance of the risks in the NZ context. Before questions began being asked of Landcare and the DBRSG, this wasn’t happening and there was no technical advisory group in place to oversee the necessary research. The public health issues are indeed ‘hot button’ because the consequences of infection from these faecal pathogens can be very severe. For example, severe kidney damage can occur in children infected with E.coli 0157:H7. Dung beetles can carry this bug. Is it OK if even one kid picks up an 0157:H7-contaminated dung beetle that has flown into his house, gets infected and then spreads this highly contagious bacteria to his family and school mates? Maybe you are happy to accept this risk and are prepared to introduce dung beetles to your farm. The problem is that in so doing, you are requiring your neighbours and eventually your entire town-and-country region to also take this risk because these big beetles can fly long distances in search of the next meal (or to lights). They are considered highly invasive in many countries. Where I farm, farmers don’t like their neighbours or even worse unknown scientists and bureaucrats making such decisions for them. Unfortunately, the epidemiological study you would like to read comparing the relative importance of dung beetles to other causes of human infections hasn’t been done. One reason for that is that by the time the clinical signs of infection develop it is very difficult to work out where the infection was picked up from. For instance, approximately 6% of Australian’s have an episode of diarrhoea per month but the cause of by far the majority of these episodes is unknown. Most but not all of the sources of infection you mention can result in human illness from faecal pathogens. The key question in relation to dung beetles is will their introduction significantly increase the amount of infection already occurring. In Australia, dung beetles markedly lowered the numbers of bush and buffalo flies. Thus, any new infections caused by dung beetles in Australia were probably off-set by reduced infections caused by flies. In New Zealand, dung beetles will not reduce fly numbers so any new infections transmitted by dung beetles will add to the total disease burden. Research is required to assess how significant the increase in infections is likely to be. The starting point for this research is to determine the quantity of E. coli (as an indicator of the degree of faecal pathogen contamination) on the dung beetles. That is somewhat trickier than simply culturing E.coli. A bit more than DUH :). It will indeed be good if the belated trials by Landcare do show that dung beetles are capable in some circumstances of reducing run off. However, be careful in generalising the results beyond the specific conditions used in the trial. The small number of published trials that show benefits are usually carefully designed to optimise the results. For instance, the researchers usually use dung from beef cattle on organic farms (to avoid drench residues), avoid the typical wet dairy cattle faeces that dung beetles don’t utilise well, do the work under cages so they can add very high numbers of beetles, optimise the season to ensure beetles are highly active, and carefully select quantity and timing of artificial rainfall events. Studies that don’t take these steps struggle to show significant differences. Some studies show some downsides of beetle activity like greater sediment in the run off. There are also quite a few studies showing that rapid shallow burial of faeces (by mechanical means) increases the number of pathogens on pastures. And of course, the picture is further complicated by the fact that much of our run-off problems are from point sources like drains or from sub-surface drainage – depending on slope, soil conditions and rainfall. I’d be happy to direct you to some of these publications if you are interested. Unfortunately, nothing is simple and while dung beetles may help in selected circumstances they will not be a silver bullet. Depressingly, water quality is still declining in many areas of Australia in spite of many years of dung beetle introductions. Cheers Grant

  • Stephen Thorpe • 2 years ago

    Once again we have someone (Andrew Barber) arguing for the benefits (which nobody disputes), but failing to address the risks. The caged trial on nutrient runoff sounds to me like it is simply designed to once again reaffirm the benefits! To call it "part of a cautionary approach" is a joke, surely? The cautionary approach is to test the risks, not to reaffirm the benefits! Yes, the dung beetles would probably solve the runoff problem, but WHAT ELSE might they do? Oh well, don't come running to us if your farm dogs start dying of oesophagal tumours ...

  • Andrew Barber • 2 years ago

    Hi Alex, I am the project manager of the Dung Beetle Release Strategy Group (DBRSG), a farmer led team who have gained permission from the Environmental Protection Agency to import dung beetles. In response to your questions I would like to direct you to our website Here you will find a wealth of information. I suggest that you look at the “Benefits” page. The first three papers under the section “Improved soil health and reduced runoff” are very interesting. The Doube report is a very in-depth analysis; the pages that you will find particularly interesting are 160 – 164 (beetles increase water infiltration rates which lead to less nutrient runoff, plus many other benefits). As part of our cautionary approach we have just completed a caged trial on nutrient runoff. While the results are currently being written up, we are told that the reduction in nutrient runoff is spectacular. This project is being driven by a group of far sighted farmers, who have taken ownership of the nutrient run-off problem and are trying to develop a long term solution.

  • Stephen Thorpe • 2 years ago

    Hi Alex, You say [quote]if dung beetles can help with that, then I’m all in favour[unquote]. If you think about that for a moment, you might see what is wrong with it. Sure, the beetles can help with that! That's what they do. The problem is about possible side-effects. You should be taking these into account before you decide whether or not you are in favour. Solving one problem can create other problems. We need to be able to have confidence that the OVERALL result is going to be a positive one, not just that one problem gets solved. Landcare haven't addressed this issue properly, probably because to do so would render the whole project uneconomical for them. The whole point here is that little or no research of the kind that you want to read has been done! Some of us believe that this research needs to be done BEFORE we start releasing dung beetles willy nilly. I think also that you need to bear in mind that pathogens can be very specific to particular hosts and vectors, so the pathogen pathways that you mention are already commonplace in N.Z. are not necessarily relevant. Dung beetles, not flies, are implicated as vectors of canine spirocercosis overseas. It is not impossible that the introduction of the dung beetles to N.Z. could lead to an outbreak of spirocercosis among farm dogs. No research has been done to determine the likelihood or otherwise of this happening in N.Z. You can read about the disease in South Africa here: (I hope you have a strong stomach!)

  • Alexander Wall • 2 years ago

    I suppose it makes sense for those opposed to the release of dung beetles to hit on a hot-button issue like public health. Probably guarantees that ‘mother of ten’ will get agitated, so we can expect to see more of it. As a farmer. I’m much more interested in having available as many options as possible for addressing the serious run-off problem we have in this country, and if dung beetles can help with that, then I’m all in favour. I wonder if you scientific boffins here could leave off sparring with one another just long enough to point us in the direction of any dung beetle / run-off research that may have been done, because I’d like to read it for myself. And while you’re at it, I don’t even know what sort of analysis its called, but has anyone done one of those studies comparing the number of actual cases of any sort of human infection caused (in a comparable environment) by dung beetles with those caused by other means? Think bathroom taps & door-handles, the rodents and other insects - including flies and mosquitoes - that have lived alongside us and all sorts of dung forever, the family cat that licks its arse and then itself all over, or the dog that does the same and then leaps up to lick someone on the face…etc. I imagine a study that quantifies and compares the actual public health risks would contribute to a much more useful debate than homing in on any real or imagined risk from dung beetles. And hey, seriously, if a scientist couldn’t find e-coli on or inside a dung beetle (DUH!), then following a different career path would be an obvious option.

  • Stephen Thorpe • 2 years ago

    On Twitter, Janine has just made this comment to me: @stho002 You on the other hand have a glaring, irrational grudge and haven't declared you affiliation Well, firstly, it is posted on several places around the web that I am an honorary research associate at University of Auckland, in the Faculty of Science, of which Prof. Guilford is the dean. So, that is my affiliation. However, unlike Janine, who is offering opinions, I am basically just pointing things out (published references to risks involving dung beetles, etc.), so my objectivity or otherwise is less of an issue. As for an "irrational grudge", well I assume I have some idea what is meant, but I question its alleged "irrationality" and its relevance here. When the dung beetle issue first came up a couple of years ago, I maintained a high level of neutrality/indifference to the issue, mainly because there didn't then seem to be much in the way of literature available on the web linking dung beetles to any particular risks. It would have been very easy for me to have sided with UoA on this issue, as I am eternally grateful to them for "catching me" when Landcare "threw me out the window" in 2007, but I didn't, due to the lack of evidence at that time of risks posed by the beetles. Now there is such evidence in the form of peer reviewed literature on the web, so I have changed my mind, whereas Landcare seem incapable of changing their mind once they get going on something. Do I harbour a "grudge"? Maybe, I really don't know, but what I do know is that I really hate to see sloppy science being trotted out in the name of profitability, and the dung beetle issue isn't the only example ...

  • Stephen Thorpe • 2 years ago

    That's a bit harsh, Janine! It would have been better for you to have simply declared your real identity and affiliations from the beginning, to prevent any such misunderstandings. Also, anybody with your affiliations would have a hard time convincing people of their neutrality/objectivity, so I'm sure it was nothing personal, as I'm pretty sure Prof. Guilford didn't even know who you were until relatively late in this exchange (he referred to you as "Pam" at one point below!) You say that you grew up with dung beetles, and that they weren't a risk, but how do you know they weren't a risk? Because nothing bad happened to you? But how do you know that you weren't just lucky that nothing bad happened to you? I'm not sure that we understand the same thing by "risk" ...

  • JanPay • 2 years ago

    Hi Grant, Only one thing to add. You grossly underestimate how highly I value my ability and freedom to make an independent judgement. How insulting that you think I am so easily swayed and incapable of forming my own objective assessment of the science. The very best relationships are based on freedom to express independent thought and to conduct independent analysis. My experience covers both public health and entomology. I grew up with dung beetles all around and they weren't a risk. You might also want to reassess your illusion that because I'm not a doctor or vet that one of my core values isn't to "first, do no harm". Risk doesn't bear little consequence to me; it is just that my interpretation of the data and evidence of risk is different to yours. You need to be aware of this nuance before you make grossly incorrect judgements about people's core values.

  • Stephen Thorpe • 2 years ago

    Yes, and I would just like to add that until such time, if ever, that the risks can be quantified with any precision, the potential benefits must be weighed against the worst case scenario (i.e. "100 bullets in the gun"), because that is what we are effectively risking, even if the actual, but unknown, risk is low. So, we must ask, firstly, is there really a serious problem with dung on farms that requires a solution? If so, are we willing to risk the health of our pets, our children, and ourselves, to solve it?? It is all too easy these days for CRIs to stoop to doing poor quality science so as to increase turnaround times for funded projects in order to maintain/maximise profitability, but surely the biosecurity of our country should not be held hostage to that??

  • Grant Guilford • 2 years ago

    Hi Janine – yes – the doubts the about the degree of benefits, quality of the risk assessment and the scale of the risks can be debated ad nauseum. In such situations of uncertainty, the best approach is to undertake the necessary research to reduce the uncertainty and better define the risk:benefit ratio. More research prior to release is clearly required. Another approach is to seek the professional opinion of specialists such as the Medical Officer of Health at the Auckland Regional Public Health Service (ARPHS). The professional written opinion of this highly qualified medical professional (MBChB, MPH, FAFPHM, FNZCPHM) was conveyed by letter to Landcare (copied to me) on the 7th May 2012. Her conclusion was that the ARPHS “does not find that there is sufficient basis for dismissing the potential risks posed by dung beetles”. With the greatest respect to you and your Landcare associates (I’ll leave you to declare your less than arm’s length relationship with Landcare), it is clear that this professional opinion should carry more weight regarding the risk to the public than the impassioned beliefs of entomologists and ecologists. Medical and veterinary professionals are strongly wedded to a shared core value of ‘first, do no harm’. Biosecurity, human health and animal health are not abstract games where risk bears little consequence. Until the necessary research is done the precautionary principle must prevail.

  • Stephen Thorpe • 2 years ago

    PS: The number of cases of canine spirocercosis in Australia is at least 3 and counting, see Trueman et al. (1980) (DOI: 10.1111/j.1751-0813.1980.tb02573.x) I don't expect every case is published and findable by Google search. While the disease is most prevalent in warmer climates, this may be correlated with the fact that most big flying dung beetles naturally occur in such warm climates, but if they can survive in more temperate areas like N.Z., then perhaps the disease can as well ...

  • Stephen Thorpe • 2 years ago

    Hi Janine, I'm not sure that I am being "speculative" at all ... rather I think that I am being CAUTIOUS (which sort of is speculation about possible negative consequences). I would say that the Australian experience indicates that there isn't credible risk IN AUSTRALIA, but N.Z. isn't Australia, and differs from Australia most relevantly in the present context in not already having lots of big dung beetles flying around as part of the natural environment. Australia might have higher levels of gastrointestinal disease relative to if it had no big flying dung beetles, it is just that it has always had some. Also, given that the original answer in the ERMA application was simply "no" to there being any risk of them acting as vectors of diseases, it is hard to be convinced that this possibility has been "carefully reviewed" - indeed if it has been, then it was probably only as a result of Prof. Guilford and his colleagues raising concerns over this matter. Landcare just seemed to "see no evil, hear no evil, speak no evil" on the issue! In the real world, risks can rarely be quantified. We just don't know if the risk is big or small. This makes it effectively a big risk. By analogy, suppose you played Russian roulette (1 shot) with a gun that can hold 100 bullets, and you don't know how many bullets are in it. If in fact there is just one bullet, then the risk of killing yourself is small. But, if you don't know that, then you are taking a BIG RISK! As far as you know, there could be 100 bullets! Mere speculation, or due caution?? Cheers, Stephen

  • JanPay • 2 years ago

    Hi Grant and Stephen, We can discuss these various highly speculative risks until the cows and their dung beetles come home. They are highly speculative because the Australian experience indicates that there isn't credible risk. In New Zealand the risk assessment has been thoroughly done and all these issues already carefully reviewed – several times – by people with more expertise than me. Also this was by people who did not stand to benefit or lose from dung beetle introduction. Stephen, it is not about finding an absence of risk – it is weighing up the risks against the benefits. It’s relatively easy to scaremonger and drum up very speculative, exaggerated risks in an attempt to stifle progress. Australia has had lots of dung beetles for 40 years and doesn't does not have an unmanageable Spirocerca lupi problem (2 cases out of all the domestic dogs in Australia over 40 years). Australia and Northland do not have significantly higher incidences of gastro-enteric disease. Grant, I don’t work at Landcare. It isn’t about just me having access to your report. Why are you so reluctant to open it and the associated review on to a public forum? Surely if you are going to refer to something in press it needs to be accessible from you to the readers? Your microbiology is also unconvincing. It is highly tenuous to extrapolate finding dung beetles at farmhouse lights to a major dung beetle superhighway between rural and urban areas. Also you give no context to the E.coli numbers on dung beetles. The presentation of numbers without context is a hall mark of scaremongering. Where were these dung beetles that you tested taken from? Were they the dung beetles found around farmhouse lights, school yards etc? Did you actually find any pathogenic E. coli in these numbers or is their presence again speculative? How do these numbers compare with a multitude of other common garden objects and organisms that children come across in their explorations?

  • Stephen Thorpe • 2 years ago

    Furthermore, one of the species approved for release is Onthophagus gazella (=Digitonthophagus gazella). This species is a known vector of Spirocerca lupi (, though it is not thought to be a "major" vector, at least not in USA ( Nevertheless, O. gazella has spread so rapidly where it has been released that the term "invasive" has been used in relation to it ( So, once it is here, there is probably no getting rid of it. Note that the other countries where it has become established, unlike N.Z., already have a native fauna of big flying dung beetles, so it introduces nothing radically different. I don't think we can look to experience overseas to predict how it will behave here, with no similar beetles here already ... only one way to find out, and then it's too late ...

  • Stephen Thorpe • 2 years ago

    Here is an interesting reference on the flight behaviour of that introduced dung beetle (Copris incertus) in Northland: [Quote]Nightly catches were usually less than 12 per night, but mass catches of up to 50 also occurred[unquote] Probably all flying noctural insects are attracted to artificial lights, so you could end up with up to 50 of these things in your bathroom if the window was open on a warm summer night! At present, such a possibility is limited within N.Z. to one or two small and sparsely populated rural areas in North Auckland, but widespread releases all over the country would radically increase the chances. The number of potential pathogens may be higher the wider the area covered, and also the chances of new pathogens arriving in the country may be higher nearer to major ports, where there are currently no big bodied flying dung beetles ...

  • Grant Guilford • 2 years ago

    Hi Janine – yes, it is disappointing that the lack of quality ‘before and after’ data makes it very difficult to assess the impacts of dung beetles in Australia – both positive and negative. The key groups in which a public health risk would manifest are those naïve to on-farm pathogens e.g. young children or adults from urban areas coming directly in contact with contaminated beetles (through the handling of beetles attracted to the lights of households, school yards, peri-rural communities etc) or with beetle excreta in roof-collected tank water. i.e. there wouldn’t be any reason to expect consistent differences in incidences of gastroenteritis between rural and urban populations. If anything, dung beetles would help even up such differences by cheerfully shuttling farm bugs to town. The dung beetle in Northland is reported to be attracted to the lights of farmhouses. The University of Auckland has just finished looking at their microbiology and found each to carry greater than 100,000 E. coli organisms per beetle. The dose of pathogenic E.coli required for gastroenteritis in healthy adults ranges from ten organisms to 1 million organisms depending on the strain. The infective dose is lower in children. Thus, it is plausible that even one beetle could carry enough pathogenic bacteria to cause infectious gastroenteritis in vulnerable people. Until the likelihood of pathogenic bacteria on (or in) beetles being transferred to in-contact people is assessed by further research, it would seem a sensible precaution to not repeat the Northland situation in other parts of the country. PS the report for the EPA on dung beetles as vectors and reservoirs you want to read was also given to your close colleagues in the Landcare group that is championing the introduction of the dung beetles. You might find it easier to pick up a copy from them.

  • Stephen Thorpe • 2 years ago

    Hi Janine, Actually there have been AT LEAST 2 cases of the disease in Australia (see At any rate, my main point was that this example demonstrates that there indeed are risks of dung beetles acting as vectors of diseases. Also, N.Z. is unique in currently lacking large bodied flying dung beetles (except for Copris incertus, which has restricted distribution), so no direct comparison is valid with other countries like Australia. Also, to quote this 2008 article (see [quote]It is not known exactly which or how many species of dung beetles transmit this parasite or what the effect of dung preference on susceptible and nonsusceptible dung beetle species is[unquote]. I'm not sure what you understand by the term "risk", but this looks like one to me! Cheers, Stephen

  • JanPay • 2 years ago

    Hi Stephen, Again the actual evidence of risk isn't beyond negligible here. Dung beetles have been in Australia for 40 years and there has been one case in 1972, in a stray dog from Kununurra (Chaneet 1972, In addition in one of the articles that you have linked to they state clearly that the problematic dung beetles are those that are specialists on omnivore dung - dogs, pigs etc. Not the cow dung -herbivore dung beetles that will be the ones introduced.

  • Stephen Thorpe • 2 years ago

    Hi Janine, There is a mounting body of scientific literature overseas linking dung beetles to a nasty disease of domestic dogs called canine spirocercosis. The disease is caused by a worm, and dung beetles act as vectors. This much is fact, see: It is also fact that the worm has been found in N.Z. on at least one occasion, see: It is not thought to be established in N.Z. at present, but this might be due to the lack of MANY LARGE FLYING dung beetles to act as vectors. Add the dung beetles, and who knows? It is a risk. The fact that Copris incertus is limited in distribution in N.Z. lessens the likelihood of it acting as a vector, but the proposed introductions are intended to spread large flying dung beetles all over the country! At any rate, the guy who answered "no" on the original ERMA application to the question "could they act as vectors of disease?" was just a tad "fast and loose", don't you think, especially when you consider that his old PhD supervisor in S. Africa was at that time (and subsequently) researching the role of dung beetles as vectors of Spirocerca lupi in S. Africa! Cheers, Stephen

  • JanPay • 2 years ago

    Hi Grant, If I was the scientist responsible for the risk assessment then indeed I would do a thorough literature review. However I don’t need to because it has already been done by scientists with considerably more experience in the area. They found that the risks due to introduction of dung beetle were negligible and this is part of the EPA documentation I linked to below. I find it odd that you need to refer me to a series of nameless people in large organisations rather than have a public literature review available supporting your arguments. Where is your report and the peer reviewer’s response? Why can’t you make them accessible? Since you have mentioned conflict of interest – I wonder if a company which didn’t have the foresight to develop dung beetle friendly drenches (which do exist) might have a vested interest as they are likely to lose market share if farmers switch brands to encourage dung beetles onto their properties. A delay in dung beetle release due to frivolous research would help stop this loss of market share but unfortunately protect a company that is a bit behind the eight ball wouldn’t it? Benefits of dung beetles have not been limited to Australia and extend beyond reductions in fly populations (Nichols et al 2008, They are considered valuable by farmers in Hawaii, United States of America, South America, their native range – Europe, and more. New Zealand doesn’t have a monopoly on wet soils and sloppy poo. Indeed several pasture ecosystems in Australia e.g. Tasmania, monsoon Queensland and Australia have periods of extremely wet soils. There is a suite of dung beetle species. There will be some species much more suited to wet New Zealand soils. I’m surprised you think so little of Australian public funding bodies that they fund decades of research on dung beetles without flawless evidence of impact. I’m sure the small group of dung beetle scientists in Australia would be highly chuffed to know that you think they have been able to maintain some sort of massive conspiracy exaggerating dung beetle benefits for 40 years and are still doing so. Incidentally no-one makes massive profit from dung beetle sales; hardly fuel for conflict of interest – unlike pharmaceutical company profits. A finding that dung beetles explain a proportion of unexplained gastro-intestinal illness in Australia would be quite a coup. It would definitely make for a British Medical Journal or New England Journal of Medicine publication. You’ve had over a year to collaborate with epidemiologists in Australia and New Zealand to put together some ground breaking research. Do you have something published, submitted or in press- a big boost for your PBRF ranking? Wow it would be big. Something that people monitoring the incidence rates of gastro-intestinal illness in Australia haven’t picked up for over 40 years. The first thing I would ask is whether or not there are consistent differences in incidences of unexplained gastro-intestinal disease between rural and urban populations in all states where dung beetles have been introduced. Regional differences in gastro-intestinal disease in Australia have indeed been studied, contrary to your speculation that no-one studies gastro-intestinal illness in Australia. Funnily enough there isn’t a consistent difference in gastro-intestinal illness between urban and rural populations (Hall et al 2006, There is also one species of dung beetle already present in New Zealand and it has a fairly limited distribution. It only occurs in Northland. If dung beetles are a significant contributor to gastro-intestinal illness I would expect surveillance of these illnesses to detect a significantly higher number of incidences in the area where dung beetles occur versus the rest of New Zealand. Again there is no evidence here (Ball 2006, MOH report, As far as I am concerned the decision to allow dung beetles into New Zealand was based on a sound assessment of benefit versus risk and was a good one. Nothing you have presented yet convinces me.

  • Grant Guilford • 2 years ago

    Hi Pam there is no need for you to rely on word of mouth. You could if you wish call or email any of the people listed in the article to discuss why they wish to see good NZ-based research on risk and benefit before any release. I’m sure they would be happy to talk to you and to provide any articles you wish to review. Alternatively, have a look at the public submissions against the dung beetle introduction that are posted on the EPA website (including from AgResearch parasitologists). You might also find it interesting to search the published literature on dung beetles via Google Scholar. This is a good search engine to identify peer-reviewed scientific articles. It avoids the pitfalls of over-reliance on websites quoting the perceived Australian experience and the views of individuals with a conflict of interest from selling dung beetles. The professional opinion of AgR parasitologists that dung beetles will not reduce NZ agricultural pest fly populations is based on simple facts - such as the noxious Australian bush and buffalo flies don’t occur here - and pest fly species in NZ don’t breed in dung. Thus, unlike Australia, we will not reap the benefits of a dung beetle-driven reduction of flies. I agree that in certain circumstances, such as when rainfall and earthworm activity are low, high numbers of dung beetles may reduce pasture fouling and produce some benefits to soil structure and pasture growth. However, before NZ takes any biosecurity or public health risks over dung beetles, it is important to better understand to what degree these theoretical benefits translate to tangible outcomes for NZ farmers. As you point out, we need facts (from research) not just belief. This is important because there are many reasons the narrow theoretical promise of dung beetles may not turn into reality at NZ farm and catchment level. For example, dung beetles struggle in wet soils, don’t like the watery-dung of cattle fed green grass, and are killed or damaged by many drench and insecticide residues. Furthermore, our rotational grazing systems, ample rainfall (in most seasons!) irrigation systems and earthworms already minimise the impacts of pasture fouling. Earthworms also improve soil structure. It would be interesting to know if CSIRO would still be spending money on introducing dung beetles were it not for the importance of reducing pest flies in Australia. Certainly, many of the other benefits envisaged by the NZ applicants to ERMA have not occurred in Australia (e.g. there has not been reduced anthelmintic use, reduced fertilizer use, or improved water quality over the last 40 years). Unfortunately, the authorities in Australia do not appear to have probed the animal health and public health effects of dung beetles. Of course if you don’t look you will not find, so we simply do not know what role if any dung beetles play in Australia’s animal health issues or the thousands of human infectious gastroenteritis cases of unknown origin that are notified each year in Australia. As mentioned above, the context is very different in NZ. We are adding animal health and public health risk without the benefit of an off-set through reduced fly numbers. We also have more intensively populated farming regions, different livestock and animal health priorities, dissimilar wildlife vectors, and different topographies, soils and climate. The risk:benefit ratio is very much less attractive in NZ than in Australia.

  • JanPay • 2 years ago

    Hi Grant, I'd be a fool to take these concerns based on word of mouth. Let's have open public and scientific debate on these expert opinions. You seem to be shirking from this. Show me the analysis and sound reasoning. I’m afraid, "Agrisearch's fly experts don't believe" doesn’t cut the mustard. Belief is not what is needed here. Dung beetles have significant benefits which extend beyond reductions in fly populations, including increased pasture productivity and reduced nitrogen run-off. There is an equal if not much greater weight of published expertise and analysis in all the fields you have mentioned that cite negligible risks. Here is a sample of just some of the documentation;; CSIRO are still introducing new species Would they still be doing that if the risks you mentioned exist? Where is the smoking gun? None of "your" experts took part in the open risk assessment process. There was ample time to comment and no-one did. Your current campaign bears striking resemblance to a T.S. Eliot poem. Have some of your experts stand up by their claims and identify themselves. Place your report and its peer review in the public domain for open, scientific debate. Anything less and the process of risk assessment is sound and your statements remain, “Shape without form, shade without colour, Paralyzed force, gesture without motion;” and your experts are shadows.

  • Grant Guilford • 2 years ago

    Hi Jan. A bit more than 'veterinary bones' involved here. Concerns about dung beetles in the NZ context have been raised by medical microbiologists, public health experts, veterinary parasitologists and epidemiologists, biosecurity experts and environmental microbiologists in CRIs, NZ and Australian universities, councils, companies and industry organisations. NZ does not have the dung breeding flies that Australia does and AgResearch's fly experts don't believe dung beetles will reduce pest fly species on NZ farms.

  • JanPay • 2 years ago

    I am utterly gobsmacked that the Dean of Science's critique of what has been a careful, scientific and refreshingly open process comes down to his "veterinary bones". Publish a systematic review on the issue and I might be convinced. Superstition - that's just backward and jolly unscientific. For those wanting to investigate for themselves the documentation and SCIENTIFIC literature indicating that the health risks of dung beetles are nil to negligible see here and here Where is Guildford's peer reviewed report? Where is this peer review of Guildford's report? What did the reviewer's say? I grew up in Australia and dung beetles have been fantastic for the environment. They've reduced fly numbers and this is good for health. Health risks of dung beetles are currently little more than a figment of imagination.