Ivo Edwards’ Report on the Fox Eradication Program from the 16th Vertebrate Pest Management Conference

Summary: The recent admission by Professor Stephen Sarre that all the fox DNA +ve scats found in Tasmania could be false positives http://oldtt.pixelkey.biz/index.php?/article/foxes-read-for-yourself-the-background-briefing-transcript/ completes the discrediting of the entire Fox Eradication Program (FEP) evidence for foxes ever establishing in Tasmania: –

“Ian Townsend: But the 56 fox-positive scats in your test would come within the range of false positives, wouldn’t it?
Stephen Sarre: Well, it’s right at the upper end, yeah. So there is a possibility that any of those scats are a false positive, but more testing is needed to get a really precise idea of that.”

This article reports on developments on the fox eradication front since release of the independent scientists’ tasmanianfox.com website. It includes a report from the 16th Vertebrate Pest Management Conference and analysis of up to date fox sighting data very recently made available together with a quick summary of problems with scat DNA evidence.

Introduction: The tasmanianfox.com website, posted on 2nd May, 2014, and the ABC Background Briefing program http://www.abc.net.au/radionational/programs/backgroundbriefing/2014-05-04/5418860 questioned the essential evidence for foxes ever establishing in Tasmania. Professor Stephen Sarre of the University of Canberra’s Institute of Applied Ecology, responsible for fox scat analysis, quickly responded to the critical tasmanianfox website presentations by saying, quite publicly,

( http://appliedecology.edu.au/news/foxes-in-tasmania-a-closer-look-at-dna-analyses-of-predator-scats/ ) that the independent scientists analysis only looked at the first phase of the DNA analysis while ignoring the more precise DNA sequencing second stage. The independent scientists have provided information to show that this is not the case, and explained that Dr Sarre has refused to provide the required Tasmanian fox scat data for independent verification of the second sequencing stage of his analysis.

The FEP, on the other hand, responded to the tasmanianfox.com site launch by initially posting a nasty tirade against some of the independent scientists on its Invasive Animals Facebook page, ( see part of it at http://oldtt.pixelkey.biz/index.php?/article/can-the-fox-leopard-change-its-spots/ ) The post was then hastily removed, presumably because someone in greater authority pointed out that the government in Tasmania had changed and that it was not appropriate any more to simply respond to serious reasoned criticism with irrational outbursts.

Since then the DPIPWE Invasive Species Branch (formerly the FEP) has refused to respond at all. The FEP Technical Advisory Panel members, apart from Sarre, have also been conspicuously silent. The DPIPWE Invasive Species branch also flatly refused to respond to my previous TT article http://oldtt.pixelkey.biz/index.php?/article/why-the-tasmanian-fox-eradication-program-has-been-/ which provided reasons why their program had no chance of eradicating foxes if they were present.

FEP General Manager Craig Elliott gave two fox presence related presentations at the recent (27 – 29th May) 16th Vertebrate Pest Management Conference in Brisbane. I was there along with over 300 of Australia’s top wildlife research scientists and rated him quite high for presentation, but not so good for relevant, interesting or novel content! The titles were:

“The final needles in the haystack – Moving to Stage 3 of the Tasmanian Fox Eradication Program “

“More than factsheets – Effective community engagement is needed to achieve eradication outcome”

His “final needles “ paper really just described the logistical problems associated with organising the Tasmanian FEP program and didn’t address anything contentious such as the possibility that maybe foxes never actually established at all or that there was finally a truly independent review of the FEP. Unfortunately there was only time for 2 questions, the first of which asked him about the FEP response to the tasmanianfox website? He replied candidly that DPIPWE bosses wouldn’t allow him to comment.

His second fox paper about the need for “effective community engagement” was really about the FEP relationship with official stakeholders and definitely not about engaging with critics such as on TT articles or tasmanianfox.com. Time for just a couple of questions again this time, the first of which asked about the Independent Review of the Tasmanian Fox Eradication Programme and their critical articles. His response was again that he couldn’t comment on the viewpoint of DPIPWE, but that Dr Sarre had responded from the point of view of the Uni of Canberra Institute of Applied Ecology, and that the tasmanianfox.com website had been a well-timed release, immediately following a change of government.

His concluding remark in his presentation, with which I was in agreement, (but maybe from a different perspective!) was that we shouldn’t trust all that we read on the internet. I also liked the comment from my unknown female seating companion when Mr Elliott was introduced to talk about “foxes in Tasmania”. “What foxes?” she whispered! ( Conference program details and digital version of book of presentation abstracts are available at http://www.avpc.net.au/ )

Overall, from my subjective assessment from talking to many of the conference delegates, most seemed rather bemused and uncertain about the credibility of fox presence data for Tasmania. ( Scat DNA, public sightings and carcasses ) It seems to me that the time is right to finally document the systematic flaws in the DPIPWE FEP “evidence “ for foxes, accept that the whole episode was an unfortunate mistake initiated by panic about the potential for devastation if foxes established, and put the issue behind us?

Evidence for fox presence revisited: The FEP evidence for fox presence in Tasmania is in the form of DNA +ve fox scats, fox reported sightings and fox carcasses. Let’s quickly go through the data again: –

1. Scat DNA evidence: It is now abundantly clear that the scat DNA evidence was seriously flawed. We have problems that:-

a. Sarre has been elusive about providing quantitative data concerning both scat DNA false positives and false negatives, only very recently apparently actually conducting formal tests (some 10 years after the original statements strongly implying that the DNA results were infallible! ) This information is so recent that it is still “In review”. Sarre’s very recent article http://appliedecology.edu.au/news/foxes-in-tasmania-a-closer-look-at-dna-analyses-of-predator-scats/ . cites that his false positive possibility review trial “demonstrated a very low probability of false positives”. This was from a bit over 500 analyses in a carefully controlled trial to specifically quantify false positives. i.e. he didn’t mention the .004 probability false positive figure (4 per 1000 = 40 per 10,000 scats analysed for 61 DNA + ve scats) which he seems to have inadvertently confessed to Ian Townsend in the ABC Background Briefing program? (He has NEVER mentioned any likelihood of false positive or negative errors previously) Presumably again then, if false positives account for two thirds of the Tasmanian fox scat DNA +ve results in idealised trial conditions, in a situation today where DNA scat tests have been vastly improved since tests in the early days of the FEP, and where possible contamination from introduced scats for trial purposes and displayed fox exhibits has been ruled out, then it seems likely, to put it mildly, that the scat results from 2004 –2010 had a lot more than a 4 in 1000 false positive error.

b. It was apparent from the Sarre et al 2012 paper http://www.canberra.edu.au/media-centre/2012/december/4_foxes/Foxes-in-Tasmania.pdf that inconsistencies existed regarding his evidence that “Foxes ARE widespread in Tasmania” (my emphasis!) DPIPWE has distanced itself from this landmark paper by saying that paper referred to data that was several years old. The actual number of 56 DNA +ve scats he claimed to be indisputably fox was clearly excessive (and even more so if some of the “fox like” scats are included as likely real fox DNA and possible false negative scat analysis occurred.) i.e. by simply extrapolating from his fox scat data to the known area searched for scats using largely known data on chance of locating scats, in the “great poo hunts”, thousands of foxes had to be present in Tasmania (see my previous TT article for details) http://oldtt.pixelkey.biz/index.php?/article/why-the-tasmanian-fox-eradication-program-has-been-/

c. The fact that DNA +ve scat patterns described by Sarre do nor match known fox behaviour http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.12278/abstract

d. The habitat modelling part of the 2012 paper is questionable, knowing that mainland Australian foxes occupy a vast range of habitats, in fact nearly anywhere where food is available.

e. There is absolutely no sign of living foxes in Tasmania these days (or ever!). Conceivably up to as many as possibly 100 foxes could exist unnoticed, but not thousands. i.e. no evidence from hunters, hundreds of camera traps for various projects, no poultry or lamb fox deaths (easily diagnosed if caused by foxes) and not a trace of evidence from years of systematic searching by FEP staff with trained sniffer dogs.

2 Recent reported fox sightings evidence: The following reported fox sightings data has been kindly provided by DPIPWE: –

The count includes ‘sightings’ as well as suspect carcasses and other reports, the ‘YEAR’ is based on the date of the sighting etc, not the date of reporting, and the 2014 count is up until 26 May

YEAR Count of Reports
2005 142
2006 272
2007 249
2008 319
2009 426
2010 288
2011 328
2012 299
2013 193
2014 31
TOTAL 2547

The last scat collected which tested positive for fox DNA was in July 2011. The FEP, without going so far as to actually say so, is strongly implying that the eradication program has been successful. For example the writer of the intemperate post (quickly removed) on the Invasive Animals Facebook page said “The FEP is in its third stage with a decrease in evidence indicating that eradication has, or has nearly, been achieved.” The change in reported sightings since July 2011, though, as seen from the above table, has not changed much to indicate that any eradication is imminent. The modest change can be accounted for by reduced media coverage in the last 2 years. https://www.youtube.com/watch?v=HXq_sWfHF-Y&feature=player_embedded. Information about lack of recent DNA+ve scats is meaningless without scat search intensity comparisons with previous years, which have not been disclosed.

It is apparent therefore, that reported fox sightings are not a good indicator of fox presence. The FEP can’t logically use sightings as strong evidence for fox presence up until mid 2011, and then claim in 2014 that they appear to have eradicated foxes, when reported sightings are substantially unchanged! For some strange reason, it seems that humans are prone to cognitive bias and can genuinely believe that they have seen something which is not true. Hence thousands of sincere reports of sightings for UFO’s worldwide, thylacines and pumas in Victoria, Bigfoot in the US, (over 3000 sightings, about the same as Tasmanian foxes – http://www.joshuastevens.net/visualization/squatch-watch-92-years-of-bigfoot-sightings-in-us-and-canada/ ) and the Loch Ness monster in Scotland.

This does not reflect well on the FEP or the Invasive Animals CRC who have used reductions in fox sightings following poisoning operations as evidence of fox poisoning efficacy. For example see the Saunders et al 2006 review http://www.feral.org.au/wp-content/uploads/2010/03/FoxReview_Web.pdf : – “Superficially at least, they support the observation that baiting is having an effect on foxes and is resulting in a decline in sightings”.

Nick Mooney’s evidence to the Parliamentary Enquiry is another example: – http://www.parliament.tas.gov.au/ctee/REPORTS/Fox%20Eradication%20Report%20-%2024%20DecemberFinal.pdf “Mr Mooney made the observation that:-
Where and when we have baited we have driven a number of evidence indices down. If we relate our material evidence to the amount of baiting we are doing, there a good inverse relationship. I have graphs that can show that.”

3. Fox Carcasses and other physical evidence:

The 17 reported incidents of fox physical remains occurring between 1998 and 2009 which have been used by the FEP as evidence of fox presence in Tasmania have been exhaustively studied. Only the 1998 single fox incursion at Burnie was universally rated as highly credible. A few of the other incidents were rated as having some degree of credibility.

Significantly, no physical evidence has been forthcoming since 2006 apart from an old fox scull conveniently found on top of a stump west of Lake Sorell, or in a shed (depending on which story line is believed) i.e. since importing fox body parts from mainland Australia was banned. Even if some or all of the original carcass evidence turned out to be real, the lack of fox body parts found in the last 8 years indicates that any foxes quickly died out naturally. In no way does it suggest a breeding population leading to “widespread” fox presence in 2012 (or 2008!). That is to say, it is not plausible that foxes were so common in the early 2000’s that they were being killed on roads and by shooters at the rate of 1 – 3 per year, and then suddenly disappeared?

Comparisons of likely fox road kill in Tasmania compared with mainland Australia are necessarily of dubious relevance because Tasmania has more road killed browser animals per km than the mainland, and hence more reason for foxes to be on roads. For what it is worth though, I easily found 6 recently killed foxes beside main roads in Victoria and NSW in 3500 km of travel in March and April this year. This included 2 on verges of the Hume highway (1 near Yass, 1 near Campbell Town). It is apparent that it is easy for anyone to access dead fox material from mainland Australia for Tasmanian “research” trials.

Postscript: I emailed FEP manager Mr Elliott a copy of a very slightly different earlier draft of this article, inviting comment and correction of any perceived mistakes. He very genially replied, corrected some minor errors, declined to comment on my subjective assessments even though he didn’t agree with some of them, and wished me good luck with the article. He pointed out that it has been a long standing policy of DPIPWE to not comment on such articles. He said my comments on his presentations drew a smile.

Ivo Edwards is an independent wildlife research scientist based at Maydena, Tasmania. He has a state of the art outdoor ecology laboratory with nocturnal native animals free to interact naturally while being filmed continuously through the night with sophisticated equipment. This has enabled exposure of lies in FEP claims of female eastern quolls and juvenile Tasmanian devils inability to be killed by Foxoff 1080 poison. It has also facilitated development of the world’s most humane and efficient animal trap for medium sized pest browsing and carnivore animals. He is in the process of promoting his traps through the FabricAnimalTraps.com.au internet site.