Wednesday, 26 September 2012

The big cat report that wasn't


Victorian Government Big Cat Study
Assessment of Evidence for the Presence in Victoria of a Wild Population of ‘Big Cats
by the CFZ's Mike Williams, 
author of Australian Big Cats: An Unnatural History of Panthers

The Victorian Government recently contracted some biologists to investigate reports of ‘panthers’ in that state in a ‘desktop study’.

The report fell down in a number of areas, not least because it set out to either prove or disprove the existence of big cats but made no attempt to collect fresh evidence, and from the outset was dealing with secondary evidence and sources.

It was a study commenced to find primary evidence of big cats in Victoria – despite the fact this office-based review was starting off with no primary evidence at all!

There are numerous statements contained within the report that do not stand up to scrutiny, quoted here in bold with clarifying statements underneath:

“Although feral Domestic Cats can attain a large size (weights of up to 16 kg have been claimed (Denny and Dickman 2010).”

This paper (Denny and Dickman 2010) is quoting Mahood (1980). The rest of the paper went on to say: "Because Mahood’s 1980 records appear so extreme and have not been approached in any subsequent studies, and the author is deceased, they are considered to have been erroneous and are not subject to further discussion."

The 16 kg  claim has not so far been substantiated.

“However, there are many thousands of reports of ‘big cats’ in the files of community cryptozoological groups and individuals.”

Let’s not try to marginalise these reports by confining them to ‘community cryptozoological groups and individuals”, the subtext of which one suspects is ‘kooks’. There are also numerous reports of big cat sightings in State Government databases collected by their own staff that have been flushed out by numerous FOI requests.

“However, some evidence cannot be dismissed entirely, including preliminary DNA evidence…”

Exactly which "case" are they talking about? If the authors are talking about the Winchelsea case, they managed to appear to try and dismiss it.

“The wide geographic spread and temporal span of claims of alien ‘big cats’ and other predators suggests that it may be a human sociological phenomenon, rather than a biological fact.”

Many standard animal reports come from a wide geographic spread and the majority of reports of any standard animal are temporal, so it’s puzzling why academics would use this language. What other predators are they talking about, and why bring it up?
Since sociology is the study of human social activity, why are they using the nonsensical term “human sociological”? No attempt is made to explain what sort of sociological phenomena the authors are trying to imply but there is the appearance of an attempt to try and pathologise the observers. Cognitive dissonance could explain the response of many academic observers to the phenomena and their attempt to play down reports due to 1/peer pressure, 2/social and academic status, 3/financial implications i.e. State Government sub-contracters and State Government staff members ... and good old ignorance.

“Consequently, claims of the presence of alien big cats, which are rarely, if ever, supported by convincing evidence, are seldom taken seriously by mainstream zoologists.”

1/The authors don't define the word "convincing". To whom, themselves?
1/The majority of mainstream Australian zoologists would know nothing about the phenomena.
2/The majority of mainstream zoologists in Australia know nothing about the behaviour of large felids.
3/The majority of mainstream zoologists would come under the same pressure mentioned above regarding cognitive dissonance.

“The Minister for Agriculture and Food Security requested, in May 2012, a science-based, preliminary assessment of the available evidence."

This is a preliminary assessment. Having scientists do a study does not mean automatically that it is "science-based".

"Further, these databases of evidence have not been subjected to independent and scientifically rigorous assessment. Without such assessment, these private databases have limited capacity to advance understanding of the issue. Where rigorous assessments have been conducted the conclusion has always been either inconclusive, or that the most parsimonious explanation involves a known species, notably Domestic Cat or Dog.”

No one appears to have edited this "scientific study". One minute the databases have not being assessed, the next minute they have been.
We must ask - who carried out the "rigorous assessments"? Or are the authors being coy when they are self-referencing ?
And let’s sort out "parsimonious" – an adjective characterised by or showing parsimony; frugal or stingy.
So it’s a stingy explanation?
We agree with this assessment, but not in the way the authors intended.

“A small number of the cases we reviewed either showed characteristics considered unusual in known species or showed characteristics known to occur in large felids, such as dragging and covering a carcass, or peeling back the skin from a limb of a carcass to access the flesh, a feat requiring considerable strength. Assessing this evidence either requires us to expand the pattern of behaviours attributable to known species of predator (for example, Dog), or deduce the presence of an unknown species. In the absence of convincing corroborating evidence for an unknown species, the former conclusion is considered the most appropriate at this stage.”

The pea and thimble in the above is, of course, "In the absence of convincing corroborating evidence for an unknown species".
Once again, convincing to whom? What cases were examined with more than a singular line of "evidence"?
Could not even one other case...corroborate a single case? Or the Winchelsea could corroborate cases near by. It’s just that the authors choose not too.
The authors even resort to deciding off their own bat to now "expand the pattern of behaviours" i.e. of dog, to try and maladroitly avoid an unknown predator conclusion. The basis of this decision(other than the obvious) is not explained of course. This is a logical fallacy called Argument from Ignorance and it is amazing that a "scientific study" used it.

“In other cases people have claimed that known predators, such as wild Dogs or Pigs, are not present in a district, and therefore predation must be caused by an unknown species (i.e. ‘big cat’). It seems more likely that our understanding of the distributions of known predators is inadequate.”

No, the authors are confused. People are pointing out the predation patterns they are seeing because they are not something they have seen associated with dogs or pigs. And pigs and wild dogs are frequently not present in their area when the livestock attacks and kills occur.
Interestingly, many of the "people" reporting these unusual patterns have also been DSE staff, who are more than aware of what dog and pig predation looks like.

In reference to "The Deakin Puma Study Group" the authors write:
“However, despite the stated aims of objectivity we have discerned some potential sources of bias in the approaches used. For example, the title given to the study ‘Deakin Puma Study’ is likely to have led to unconscious bias in the volunteer participants, predisposing them to read ‘Puma’ into inconclusive evidence.”

The authors imply that the title preceded the study, so that it could possibly influence the volunteers’ bias. Which means the authors must have researched this by contacting Deakin University, or the study’s author Dr John Henry, because how else would they know this ‘fact’? Surely a scientific report, would not present facts by guessing!
But it transpires Professor John Henry decided the title after the study was completed (pers comms).
The irony of mentioning unconscious bias is obviously lost on the authors of this “scientific study”.
No mention is made of the Deakin study actually tricking its participants by fakery, then telling them to be on their guard in future, in this report.
And there is no mention of the Deakin study’s conclusions.

“This scat became one of five pieces of evidence upon which Henry (2001) based his conclusion that there ‘is sufficient evidence from a number of intersecting sources to affirm beyond reasonable doubt the presence of a big-cat population in Western Victoria’. However, in an addendum to the report, Henry (2001) admits that the Geranium Springs scat 2 is most likely a regurgitated pellet from a Wedge-tailed Eagle."

Because Henry et al were wrong with some analysis (and admitted it!), the Deakin Study group was, by implication, wrong on all pieces of evidence, according to this report, and its findings should therefore be dismissed.
Following that exact same logic, this report’s findings should also be dismissed.

“We believe that this revised finding is indicative of the Deakin Puma Study Group falling into the understandable position of being captured by the legend it was seeking to prove.”

This patronising response is projecting its own motives on to other groups.
Why would a long and active, real scientific field study be “captured” by a “legend”? It is also normal scientific practise to admit a mistake, as the Deakin study did.

“Another case worthy of close consideration involves photographs of two clear footprints on a sandy track in Longford Pine Plantation taken in December 2005 and supplied by Richard Sealock, along with an analysis of their size and shape. We agree that these footprints are highly likely to have been made by a cat and that their reported dimensions are greater than could be explained by a Domestic Cat, however, that is as far as that line of evidence can be taken.”

Confusingly, however, there is no indication of the actual size of the prints.
Richard Sealock stated he believed the prints to be 87mm-88 mm (pers comms).
The authors had time to cut and paste leopard photos easily found on the Internet, which were not required, but had no time to cut and paste the Sealock prints or mention their size.?

“We find that none of the investigations that have focussed on secondary and tertiary evidence has succeeded in providing an unequivocal answer. We see little point in dedicating public resources to that line of inquiry.”

What “investigations” are the authors taking about? The Sealock prints, in my opinion, are giving an “unequivocal answer” – they’re large felid. Just as the Winchelsea case are odds-on Panthera pardus.

“No ‘big cat’ scats have been identified during studies involving the systematic collection and analysis of thousands of mammalian predator scats (feral Domestic Cat, wild Dog (includes Dingo), Red Fox) undertaken as part of studies of predator diet and as a mammal survey technique (for example, Brunner et al. 1976, Klare et al. 2011).”

Another pea and thimble trick.
The weakness of the systemic collection meme is below - and the above ‘argument’, as weak as it is, falls apart for identification outside the authors’ stated parameter.
We are forced to rely on the authors’ implied access to every scat report ever compiled in Victoria.
We are forced to believe that every field worker who did (by implication) find a possible outsized felid scat, would automatically know this and report it.
We are then forced to have to believe that this report would have made it into some form of study.
We are then forced to believe that scientists who supposedly are skilled in scat analysis and could identify large felid scats were always contacted and that the same scientists, who are sub-contractors, are highly skilled at identifying large felid scats.
And then we are forced to believe that this same unknown scat scientist would be unaware of what the implications were if they did report the scat was from an unknown large felid and were oblivious to the ramifications to their possible future contracts.
And, without a family identification (since species would be impossible without DNA) this hypothetical scat result would be dismissed with the wave of a hand since it did not “prove” what species of animal the scat came from.
And when the scat is identified by DNA down to species level...this is ignored anyway.
Now what about outside the “involving the systematic collection and analysis” parameters of this statement?
The Winchelsea case (discussed further down) fits the bill perfectly.

The Kurt Engel cat
“DSE arranged for the extraction and analysis of DNA from a small sample of skin taken with permission from this tail. The analysis was undertaken at the Department of Genetics, Monash University, and the result was that the sample exhibited between 97.7% and 100% sequence identity with the Domestic Cat, and only 87% sequence identity with the Leopard (Kate Charlton in lit. to Bernard Mace, 24 November 2005, copy on DSE file 85/3043-4). The length of this cat’s tail, at 65 cm, is twice that of a normal Cat (Appendix 1) but it may have been stretched during skinning, a common occurrence if care is not taken. Hence, the conclusion is that the animal was a particularly large individual of Felis catus, the Domestic Cat.”

In their haste to produce this "scientific report", did the authors not think it was odd, that if the DSE arranged the extraction and analysis, the only reference for this in all of its files is "Bernard Mace, 24 November 2005, copy on DSE file 85/3043-4)"? Why no reference to the actual DSE file?
Because Bernard Mace, who passed the sample to Charlton, was not working for the DSE. The DSE, as the authors would have known, had nothing to do with the “Engel case” what so ever. And it is worse than that…
The DSE was initially offered the tail and photos, but their staff were not the slightest bit interested.
The only plausible way the tail could have been altered in a way to have increased the length to any decent level, was not by stretching, which would have torn it. It would have required a "trick" cut further up the body, but fraud was dismissed by a Melbourne Museum biologist who examined the tail firsthand.

Australian Big Cats: An Unnatural History of Panthers (Strange Nation Publishing, 2010) tells the full story:

Melbourne Museum biologist Rory O’Brien was one of the few people to physically examine the tail soon after the animal was shot. He dismissed claims the length of the tail may have been hoaxed by skinning a part of the back hide.

“It was large, pretty long ...the tail was very thick overall and very furry and the last 3-4cm of the tail still had the remaining caudal vertebrae. It seemed pretty fresh to me,” he said. “It looked authentic…because the tail was the same colour (as the photographs). It was a uniform tail, all black. It was very bushy, but sleek and catlike in texture.”

An attempt to have the material further examined by DSE employees was rebuffed by the department.

The Engel tail was also examined by Bernard Mace, a long-time cat researcher with extensive field experience, who was also of the opinion the tail was genuine and had not been tampered with.

So we have two scientists who examined the fresh physical evidence, but two biologists looking at photographs have a more valid scientific opinion? Hmmmmm…

Earlier in this post I referred to the Winchelsea faecal sample, which is a highlight of the report since it basically is saying that secondary evidence led to a species ID using DNA.

Winchelsea faecal sample
This result seems not to have been formally conveyed to any Government Department and has not been publicised before this study, apart from a passing reference in Australian Big Cats: An Unnatural History of Panthers (Strange Nation Publishing, 2010). Scientist Stephen Frankenberg has personally conveyed that the decision not to publish this information was largely because the result could not be considered 100% reliable due to a small possibility of contamination (note that Triggs had leopard hairs in her workshop).

The contamination issue was a strawman argument.
If there was contamination, then both ‘control’ hair (zoo) and Winchelsea sample hair would have had the same DNA sequence exactly. They would have, too, since they would, by implication, be just from the same animal.
The two samples were not the same animal since they shared similar but not identical DNA sequences (to ID the animals as leopard), but they also had a slight difference.
They were two different leopards (pers comms, D. Cass)!

Carrie Magnik BSc Hons thesis
These three cases highlight the difficulties in extracting and identifying traces of DNA from secondary sources such as carcasses and scats. Even when successful at extracting and amplifying DNA, the results will be probabilistic rather than binary.

Confusing language structure. All DNA results are essentially probabilistic, so what?
They are the gold standard for species ID.
It’s almost like the authors are trying to lessen the importance of DNA results by using the term “probabilistic”.
The term “binary” is implied (possibly) to have some greater scientific importance than mere probabilistic.
Binary means composed of two pieces or two parts, yet paradoxically, in this specific sense, DNA results are always a binary result - the sample and the extraction - so its use is baffling.
Veracity of available evidence
No unequivocal evidence supporting the presence of ‘big cats’ in Victoria was found in this study.

We are guessing the authors mean “a body on the table”.

Perhaps even more compelling is the lack of evidence.

The authors appear to ignore their own conclusions.
see below

"Notwithstanding conclusions 1-3, some evidence cannot be dismissed entirely, including preliminary DNA evidence, footprints and some behaviours that seem to be outside the known behavioural repertoire of known predators in Victoria." 
If they cannot check what meagre facts they present here, and cannot even check their own report for inconsistencies like this, why are the general public supposed to give any credence to this report?
When the authors of this report have made mistakes, “chance” would dictate that unless they have some sort of bias, the mistakes would be random.
Some of the mistakes would inadvertently support the possible existence of big cats in Victoria, and some against this possibility.
But what is interesting is that all the major mistakes are towards supporting the government’s views, and none for the opposite view.
The probability of that sort of result, happening by chance, would be zero.
The report was not science-based but rather just a collection of anecdotes and opinions that seemingly, in spite of itself, made several interesting points such as the Winchelsea DNA result.
Conclusion number 4 and the six recommendations were excellent and ‘on the money’, but sadly, they will never be implemented.
This desktop study of old reports was overwhelmingly a textbook example of confirmation bias, and merely a tick of the box for a relatively new state government eager to deliver on an election promise.
It’s also the latest in a long line of ‘government investigations’ into a phenomena that has stalked the states of NSW and WA, delivering yet another substandard result on what is surely one of Australia’s most compelling wildlife mysteries.

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