4 October 2022

Science of counting kangaroos called into question once more, so how do they do it?

| Lottie Twyford
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An eastern grey kangaroo

The ACT Government has defended its kangaroo counting methodology. Photo: Michelle Kroll.

They’re quick, they blend in with the landscape, and they often hop from the sight of humans.

So how does the government’s team of ecologists actually count how many kangaroos are in the city’s nature reserves?

That remains a contentious subject for some.

Opponents of the annual kangaroo cull argue the government is overstating how many of the creatures there are in the landscape.

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Environment Minister Rebecca Vassarotti explained how kangaroos are counted during budget estimates hearings last month.

She said while direct counts played a role in the kangaroo count, they were generally lengthy processes as they involved observers going through an entire site without missing any and then going back again and again to ensure a reliable count.

In her response to the petitioners, Ms Vassarotti said direct counts were only suitable for sites with open vegetation and were difficult to conduct in large areas with dense vegetation.

Instead, the ACT Government uses sweep counts and walked line transect counts – methods that have recently been peer-reviewed.

Sweep counts involve coordinated lines of people walking across the site and counting kangaroos that move through the line – useful for larger areas and sites with “issues” around vegetation and terrain.

It requires careful coordination of the counters, aided by two-way radios and maps, Ms Vassarotti said.

READ ALSO ‘Blunt trauma’ used to kill joeys as research continues into kangaroo cull replacements

In most cases, the government relies on walked-line transect surveys.

These are conducted across 11 days, early in the morning when kangaroos are evenly dispersed across the grazing landscape. They don’t take place in strong wind, heavy fog or rain.

While they are pretty technical, the surveys essentially chop the landscape into different sections, and observers walk along about 44 km of transects (lines) per nature reserve to count kangaroos. They take into account features like roads and water bodies.

table showing act government kangaroo counts

ACT Government 2022 kangaroo counts. Image: Screenshot.

The ACT Government’s 2022 count is publicly available, and its report stated this year’s counts were likely to have underestimated kangaroo populations due to high vegetation.

table showing kangaroo counts

ACT Government kangaroo counts and count types. Image: Screenshot.

But these numbers aren’t good enough for the Save Canberra’s Kangaroos group which has, over the last two and a half years, been counting kangaroos through the aforementioned citizen science method of direct counts.

In a report published in May this year, the citizen scientists said they could only find 4074 kangaroos in 37 nature reserves around the Territory after “systematically” searching for them.

That figure compares to the 16,863 the government’s ecologists and observers found.

The report’s authors stated it was not intended to be a census of kangaroos to see if there was an overabundance of the animals.

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ACT Flora and Fauna Conservator Bren Burkevics said the discrepancy in the actual versus recommended cull comes down to the small window in which a cull is permitted, logistics and safety.

Mr Burkevics said differences in opinions about kangaroo count numbers weren’t “unexpected”.

“What I can say is the survey is conducted by staff at EPSDD who are senior ecologists who have been conducting them for years to best practice ecological standards,” he said.

“We know that when kangaroos are overabundant, they can overgraze some of the ACT’s reserves that are home to critically endangered woodlands and grasslands.”

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A recent petition has been started online by the Belco Party urging the government to halt the cull while an independent review takes place.

It follows the Legislative Assembly Standing Committee on Environment, Climate Change and Biodiversity only last month rejecting further examination of a different petition, signed by 853 Canberrans, which called for essentially the same thing.

The committee argued in response the Territory’s kangaroo management program had already been “extensively reviewed”, including in four ACAT hearings.

In the following year, the government says it will conduct an opinion poll of ACT residents, review its 2017 kangaroo management plan and undertake an independent veterinary audit of the program.

READ ALSO Where do kangaroos go when they die? And other facts about Canberra’s conservation cull

Kangaroo culls have been underway in the Territory for the last 15 years. At the close of this year’s cull, 1645 animals were killed.

The Territory government is also trialling a fertility control program whereby the contraceptive dart GonaCon is shot at females.

It’s hoped the $300,000-a-year program will offer a more humane approach to controlling kangaroo populations and that wider use of the drug will reduce the need to kill animals.

Ms Vassarotti said it is challenging, but most of the community supported the need to manage kangaroo populations.

“It is disappointing but sadly unsurprising that the Belco Party is peddling misinformation about the ACT’s kangaroo management to find relevance again. If the Belco Party is concerned about the science of the cull, the ACT’s kangaroo management policy and extensive peer-reviewed research are publicly available online,” she said in a statement.

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This post is not about any individual. Indeed, it is in this thread only because that is a proximate hook for a general comment.

Unrelated to anything here, I chanced across this site recently:
Further down the page, it contains an interesting table on literacy levels, and still further down I found this:
“An education doesn’t guarantee a reading level that matches the qualification. For example, about 30% of Australians have a diploma or higher, but only 1.2% of Australians can read at that level.”

That soon associated with a couple of other facts.
Firstly, I have noticed here over several threads that many people seem to have little grasp of, or time for, proportions rather than raw numbers, yet proportions are taught in Years 6-7 and form a minimal (though important) level of statistical numeracy. Perhaps the real curve of numeracy will follow a similar pattern to that of literacy above.
Secondly, it is established in research that more than half of people will rate themselves above average, in (for example) driving, intelligence, ability at their preferred activity and so on (although the effect depends on how you frame the question). People mis-perceive what is average.

My proposition is that people will tend to over-estimate their scientific capability; consistent with literacy and numeracy being in reality lower than one might otherwise expect for a high education. Most graduates do not improve upon the underlying skills with which they emerge from university except where it is essential and they are high performers in their field (see that 30% vs ~1% again as the example). This over-estimation is not helped by the informal title “citizen scientist” especially where there is already dedication to another interest, belief, or cause.

Feel free not to reply. I did not set the comment up for debate but as something to consider neutrally for oneself, if you wish.

Skeptic, Chewy and Phydeaux, you’re all obviously passionate supporters of your positions regarding kangaroo culling in various Canberra Nature Reserves but none of you have commented on the tables above supplied by the Minister via the ACT Environment Directorate. I think one of the problems for your position is that many of the statistics regarding kangaroo populations on the various KMUs seem to have little basis in reality for a growing number of Canberrans who are very familiar with the nature reserves. If kangaroos are this numerous, then surely, sometimes, people searching for them would find some evidence somewhere in the search areas, that kangaroos are present in the numbers claimed by the Directorate. We are aware of the WLT method, the mathematical corrections and the extrapolations – described by the Conservator in a Canberra Times article in June 2022. Perhaps you could explain a bit more for the benefit of your readers?

Motojohno, don’t try to be cute. Prior to this thread I was substantially indifferent to the culls, not even being in Canberra during most of the last decade discussions.

What happened here is that you and others have presented an evidently silly petition in which I picked out only one of the erroneous claims, yet you and rebeccam1 have both avoided answering my queries about it.
You make spurious arguments about land development while implying scientific analysis is some sort of conspiracy against [biassed] analysis by your lobby group.
You claim you are not answered when you are answered, but you don’t like answer. Any more toys left in your pram?

My interest is that you you seek to be misleading from personal interest. I dislike such behaviour, so I comment. As I implied below, if you made sense then equally I might have supported you against others. You don’t, so I won’t.

By seeking to recycle already failed arguments, you are wasting everybody’s time. Put on a placard saying “All Kangaroos are Precious (but nothing else is)” and picket the Assembly.

I’ve said nothing about any petition and nothing about any land development. If you can respond respectfully to my question, then why not do that?

Not sure how you’ve gleaned that we are “passionate supporters” of anything by simply correcting clear falsehoods made by others in this thread.

It’s obvious who has significant emotional involvement invested in this issue and it isn’t us.

And that emotional involvement from anti cull activists is exactly the problem in their attempts to claim some sort of objectivity on the issue or in their attempts to discredit the scientific research in the area.

So I’m not sure why you try to bring up these individuals personal experiences I’m the nature reserves again, the issue has been raised and answered multiple times.

Motojohno, care to declare you were not a signatory to the petition? If you can honestly do that, then I will not query you about its sillier contents.

Care to declare that you consider the land development arguments absurd, or offer additional arguments against them? If you do that then I will not imply you have any other than such a declared view.

You are recycling an answered question, pretending there are not already extensive responses in this thread from different people, yet now you try to ask respect for again flogging your decomposed horse.

Respect? I have none for your blind, repetitive, zealotry. Try to earn some by answering my first two queries in this post.

So, do you have any comments to make about the kangaroo population tables in the Riotact article?

comments on the scientific basis of counting methods used already exist in this thread multiple times and the government has provided responses to the claims made by various anti cull activists repeatedly.

Similar to Rebecca, you seem to want to continue asking the same questions when you don’t get the answer you want.

And as you’ve posted below, your opposition seems to mainly exist around the morality of culling kangaroos, so why do you care what the counts are? You wouldn’t be supportive of them anyway.

Almost like you’re attempting to use questions around the scientific accuracy of the counting methods as cover for your true position.

Yes, Motojohno. You may read those comments already made by me and others, as I noted in my 12:59 pm post just above yours. Too hard for the average zealot?

So, do you have any answers to my queries in that 12:59 pm post? Or are you still running away?

Motojohnno, I am qualified to explain the count methods and results but there is no hope of doing so in comments. Like other ecologists I know, it took me quite a while to understand the Distance Estimation (line transect) method, many years ago, including using it in different contexts. There are three books in my study about how Distance Estimation works, which I have perused many times, and I have read quite a few papers as well. There are many books available on how to estimate animal abundance in different ways, but those three books are SOLELY about this one method. I remember telling students who I trained in the method that if you haven’t read the introductory book, you can’t be competent. Similarly, I had read quite a lot about faecal pellet counts and also used that method a bit before I understood it properly. (The early kangaroo counts in Canberra Nature Park were done using pellet counts but the method was later replaced by Distance Estimation, Direct Counts and Sweep Counts, which are less vulnerable to rainy weather and, for kangaroos, produce results that are not significantly different statistically at lower cost.)

So a decent explanation of the counting methods would be sort of like running a university course. There is no way to do it in a comment. If I tried, the limited sort of thing I could do would only act as bait for those looking for things to criticise.

Now we come to what seems to be the nub of the counts issue. It is astonishingly similar to what is happening with the feral horse issue in Kosciuszko. Brumby activists led by former National MP and Horse Trek businessman Peter Cochran claim the years of counts by scientists from various different institutions are wrong because in a short ride he sees very few horses. Scores of supporters who have driven past the Kiandra and Long Plain grassland areas have agreed with him on social media. The main problems, aside from scientific illiteracy (On Facebook, Cochran has even condemned people for learning things from books!) are first that he conveniently forgets the park is several hundred times bigger than the area he looks at. And second, he assumes he sees all the horses in the area he looks at. No one does that. BTW, the horse protestors are less polite than you. Lately they have claimed that the count scientists accepted bribes to exaggerate the counts, and a few days ago they delivered a note to park HQ which threatened to firebomb the homes of park staff and their families if the cull continued. So, thanks for your politeness.

But back to the counts. In my experience, the reality is that there are always more animals (of every kind) than people think, especially inexperienced people. So when you attempt the unique and novel kind of counting that ACT Animal Lib did under the direction of Ray Mjadwesh (who has no relevant training) which assumed every kangaroo was seen, you get a very false impression. Counting wildlife is not like counting cows in a paddock, not at all. There needs to be a statistical sampling design of a proven type and there needs to be statistical analysis using proven methods.

Also there needs to be an adequate counting effort. (Remember the adage that science is 99% perspiration.) The article says how much field work the line transects method requires to collect sufficient data, before they can analyse it. In each location they walk 40 km of transect over eleven days. That’s a formidable effort in 10-20 reserves (400-800 km)! And amazing how they do that even in small reserves of maybe only 2-6 sq km. Anyway, I think that if you want to put up alternative counts to challenge the official result obtained by qualified, trained and experienced scientists, then for the sake of your dignity, you should at least be willing to put in a comparable effort – not like the Animal Lib effort which covered a kilometre or so per reserve, in the middle of sunny days. With that sort of effort and misunderstanding, it is no wander the results were ridiculous.

However the bottom line is that neither kangaroo activists nor brumby protestors really are about counts. They oppose the killing of any individual animal of these species. Argument about counts are just a convenient way to attack the credibility of the cull process. But governments are bound by biodiversity laws and agreements. None of the eight Australian governments are free to adopt the position of compassionate conservationists and animal rights people that individual animals of ‘sentient’ or highly valued species should be free from lethal control (like we humans are) when that would protect non-sentient species. Biodiversity is held by our society to be of greater importance than the lives of individual ‘sentient’ animals, so the opinions of compassionate conservationists and other animal rights people should be heard, respected and not acted upon.

Thank you for your response. I first became more fully aware of the kangaroo culls in 2021 – I vaguely knew about them, but when I heard that despite the massive losses of wildlife and other destruction in Namadgi National Park (and elsewhere) because of the bushfires in 2020, I was alarmed that another cull was going ahead.
I wrote to the Minister and she emailed me references to the Kangaroo Plans of Management (2010 and 2017) which I studied. What struck me the most was the population estimates of kangaroos in the nature reserves, which I have been walking in for some years. I really wanted to see for myself the great numbers of kangaroos that are apparently inhabiting our nature reserves.
So we (my husband and I) started searching on a daily basis, not just walking along the tracks – you don’t see many that way, but searching, counting and recording. You might call it a ground truthing exercise. We were determined to find kangaroos, and wanted to see them. We used binoculars, GPS mapping, we segmented areas into manageable search areas and recorded where we found kangaroos in each nature reserve. We reasoned that if they are there in such large numbers, we would find them – at least sometimes!
We searched on most days for eight months – hundreds of hours, and over 1,300 kilometres. We are still searching, because we want to. We have spoken to scientists, politicians and activists and discussed what we were doing with them.
We have observed that our counts of kangaroos are closest to the Directorate’s when they used ‘direct counts’ in the grassland reserves. Where our counts varied greatly to the Directorate’s was where sweep counts, WLT, pellet counts and in one case ‘driven line transect’ was/were used. It seems that when ‘mathematical corrections’ and extrapolations were applied, the numbers of kangaroos determined to be in a given area, increased….exponentially. And we simply could not find them in these extraordinarily high numbers, no matter how hard we searched. We found this time and time again. We never found kangaroos in the population densities that would reflect the numbers that the Directorate repeatedly claims exist in the nature reserves where culling takes place. And this became our concern.
The claims of ‘overabundance’ – the reason for the culls – just wasn’t holding up, based on what we were seeing. We saw significant numbers of kangaroos in two reserves, but in most – certainly where culling occurs repeatedly – we found nothing like what the Directorate is claiming.
Our concerns only compounded when we heard the former Conservator announce in May 2022 that he had ‘no idea’ how many kangaroos there are in Canberra Nature Park and then confidently announce that another 1,645 would be killed in this year’s cull.
So, Skeptic, you may or may not deride our efforts and commitment, but we do have genuine concerns about the culls in Canberra Nature Park and elsewhere.
Kangaroos are slaughtered on a nightly basis all over Australia. They must be one of the most maligned and cruelly treated animals in the country. The ACT Environment Directorate has made them a scapegoat for the threats facing endangered and threatened species, when humans are to blame for the ills facing these little creatures. We care about that. We think we can and should do better.

Motojohnno, ‘mathematical corrections’ and ‘extrapolations’ are not a normal part of the Distance Sampling method, when applied to surface dwelling animals such as kangaroos (but something of the sort is used routinely for marine mammals and maybe some underground species), so if Environment ACT is using them for kangaroos I’d be interested to hear their explanation why. However I know that their counts have been peer reviewed and are highly regarded, so it seems to me almost certain that they will be using sound methods. Also the various counting methods were applied to the same five reserves several years ago, and the results of the different methods were not significantly different statistically.

Direct counts are only possible in the smallest reserves with open vegetation, so its only to be expected that your count differed more from theirs in the (larger and more complex) sites where other methods are needed.

Since you are putting in all this effort to check on their counts, why don’t you follow scientific orthodoxy and use a method that scientists will respect? If you did that, you could even publish your alternative result to give credibility to your concern about overcounting. But maybe it would be simpler and save yourself and them a lot of time if you just talked to them!

Statements about animal welfare should be factually correct Motojonno. Yes, kangaroos are treated with violence on a nightly basis. The violence of the complete destruction of their cranium by a projectile travelling faster than sound ensures their death is painless. No other species is required to be killed in this manner and it is usual for those (eg deer, pigs, foxes) to be shot in the chest. That is still a good death if it is done properly but less humane than what is required for kangaroos, yet no one ever makes complaint about the ‘cruelty’ of that shooting. You only complain about kangaroos, whose shooting is the least cruel of all shot species. If given the choice of how I was to die, I would rather go out like a kangaroo, than slowly in a hospice. I would be out in the bush with my mates. Someone would dazzle me with a bright light then I would lose the ability to perceive pain before I could even be aware that a shot had been fired.

The number of kangaroos in Canberra Nature Park could be estimated without great difficulty by extrapolating from the counts done already, but it would not have the precision of the annual counts in the reserves that are counted. But why? For the purpose of managing the cull, it would be a pointless waste of money.

Would you still be OK with anticipating that death if you were still in the prime of life and wanting to live? Or if you had dependent offspring to nurture and protect? And if it wasn’t actually your choice but you were to be murdered by someone who took your personal power from you? If I guess you wouldn’t be too happy if you were mis-shot and had to suffer the consequences. Anyway, that’s academic, it’s never likely to happen to you!

I don’t believe that kangaroo joeys experience a humane death, including here in the ACT. There is plenty of evidence to show that they are treated with complete and utter disdain, disrespect, hatred and violence (in Australia more broadly), as are adult kangaroos by some Australians.
Recently in the legislative assembly, an MLA asked the Minister and Directorate staffers if joeys are killed by clubbing. Apparently they responded that this was not correct and that they are killed by ‘blunt force trauma’. They provided further detail at the MLA’s request that they are killed by a wooden mallet (but not clubbed). I’ve seen photos of decapitated fully furred joeys…I don’t think they experienced a humane death.

I believe some people do complain about the deliberate killing of the species you’ve listed, and others.

I am unhappy about the killing of kangaroos in Canberra Nature Park because I’m unconvinced that it is necessary, wise or just (and I am entitled to my opinion). I have read the science, in fact I’ve spent just as many hours researching the Directorate’s reports and data as I have spent in the reserves over the past 12 months or so. If there are issues – that humans have created, by plonking an ever-growing capital city on top of grasslands and woodlands – with kangaroos overgrazing the grasslands – then humans should come up with a humane and decent response. Shooting is violent and in the 21st century we should do better.

Regarding the population estimates, I just wish I could find SOME evidence that the numbers claimed by the Directorate are actually there. 2,770 kangaroos on Mt Ainslie and Mt Majura? Since the cull of 2022 we and others – have spent over 50 hours trying to get close to that number and those kangaroos just keep eluding us. We’ve searched high and low.

Farrer Ridge? Culled of 297 kangaroos plus joeys in 2021. Directorate claims there are 144 there. That ridge has been searched by numerous people for hours on end. Last year, after the cull we found 32. This year we found 40 and 6 of those were at foot joeys. So, where are the others? And so it goes on. The Directorate (and the Minister) appear to be completely incurious about the on-ground experience of people who spend extraordinary amounts of time in the reserves. The Minister doggedly resists any concerns expressed by them.

Apart from all that, many Australians deeply love our wildlife – some people give their entire lives over to saving it – and that includes to kangaroos. It is emotionally painful to know about the cruelty dealt out to our unique wildlife by humans. It’s bad enough when its natural disasters; heartbreaking when it’s fellow citizens.

Skeptic9999. If it takes the reading of a entire book, if not three, to become competent in the “Distance Estimation” method, then there is Buckley’s chance that the foot folk that is engaged with the counting will all be doing the right thing all the time. So what value can one possible attribute to outcomes of such a method, other than agreeing that it is just an estimation, and a distance one at that. I would have expected a bit more common sense from someone who professes to be a skeptic, the more one which award themselves a 9999 out of 10,000.

Crappicker, enough! In these comments, most participants behaved in a respectful, adult manner, and made points genuinely. Your input is different. First, in spite of having previously made strong statements on the topic, and criticised others, you failed to acknowledge your mistake in having confused areas of developed land with nearby but different areas where culling has occurred. Now you try to suggest that the outcomes of doing something must be wrong (so wrong that it matters) if reading a book is required to fully understand the activity. It indicates we should have no faith in members of any profession e.g. dentists, doctors, vets, surveyors, lawyers, biologists and engineers. I’m repelled by such silly games. Finally you try to insult me by playing with my pseudonym. I’m not willing to interact here with children.

So so so many false statements from anti-cull activists! One cant answer them all. But I will respond to one, the oft repeated claim that the culls are to make way for development. In short, it is a LIE.

The cull by the Commonwealth Government in the Belconnen Naval Transmitter Station at Lawson is the example quoted most often. For 14 years activists have been claiming the area first culled in 2008 has been developed into suburb. That was never true and it remains a lie to this day. The entire area inside the security fence (where the culling is done) still remains as it was at the time of the cull in 2008, 100% undeveloped. A nearby area outside the security fence has been developed, but that area has never been subject to culling. Kangaroos live on both sides of the security fence, but they are separate populations. Go and look yourself, or examine the area in Google Earth or Near Map.

Likewise for the culls by the ACT Government. Nearly all of the ACT Government culls are in Nature Reserves. Nature Reserves are not developed into for suburbs. The claim that culling makes way for suburban development is just one of many lies that activists have repeated so many times that people have started to believe them.

Some correspondents (eg rebeccam1) complain that the government has been ignoring the activists. If the ACT Government ever does anything else, the majority of people in this democratic society will be seriously concerned. It is important that governments of all types continue to disregard those of us who are deluded or deceitful. Those of us capable of adult behaviour are more likely to have influence. May it always be so.

Some, like myself, are primarily against kangaroo culling in Canberra nature reserves because we find it morally repugnant to deliberately kill native animals in their habitat when we (humans) have created the problems that the ACT Environment Directorate claims kangaroos cause. A progressive and enlightened government could and should do better. Shooting and clubbing (joeys) is not the only option, just the cheapest and nastiest. Kangaroos have lived on our continent far longer than any humans and many Australians believe that they deserve better than being slaughtered for whatever reasons.

Nonsense. Simple google searches show “Defence Housing Australia has submitted plans for federal environmental approval of its Lawson North project, which includes the development of more than 47 hectares of land. The territory plan currently allows for approximately 22.5 hectares of the former Belconnen Naval Transmitting Station to be developed.”, and “The Federal Golf Club submitted on 18 May 2022 a proposal (No 2022-09201) to develop a retirement village and water infrastructure on the golf course.”, that is the golf course adjacent to the Red Hill Nature Reserve.

Yes those Google searches are simple.

The only problem being when you actually look at the detail, the amount of land used for those developments is tiny compared to the entirety of the sites, which would mostly remain grass/bushland and can never be developed due to their status and environmental legislation. The kangaroo cull is irrelevant to the development opportunities.



crappicker, No, what I wrote is not ‘nonsense’. You are wrong, because the suburban development at Lawson that you refer to, has not been culled. And none of the area that has been culled has been developed. It is simple. The area proposed for development by Defence Housing Australia is OUTSIDE the security fence around the Naval Transmitter Station. Inside the fence is one of the best natural temperate grasslands in the region and it is the only area that has been culled.

And you are wrong about the Federal Golf Club at Red Hill too. It is simple too. The suburb is built on the golf course, not on the nature reserve.

All the claims made by activists about culls being followed by development are wrong. For so many wrongful claims to be made for so many years by so many activists about something that can easily be checked, suggests that either the claims are deliberate lies or they are mistakes by unusually incompetent people who lack diligence. I think the claims are mainly the latter.

Add South Lawson and Section 66 Deakin.

Reality Theatre:
(kangaroo mob) : [munch munch munch]
(Bulldozer) : “G’day, Skippy”
(kangaroo mob) : “Er, what?” {Exeunt, stage West]

crappicker et al Theatre
(adviser) : “Minister, I propose that we pay scientists to investigate kangaroos on that land then pay people to cull some of them but leave lots more while attracting opprobrium from some sections of society over many years.”
(Minister) : “Why? Won’t they just go away when we send in bulldozers??”
(adviser) : “Er, yes, but, but, they’re kangaroos! With big herbivore teeth and they could kick over excavators and gnaw the wheels off trucks, and, and, other things!”

My last post was not quite completed before accidental posting. Suffice to add that the notion that land development cannot possibly commence before kangaroo numbers are reduced in a location yet leaving many remaining, is fatuous. cf Molonglo Valley.

Members of the public have been writing to the ACT government expressing concerns about the cull for years now. These concerns fall on deaf ears. I would consider that being ignored.

Hey rebeccam1, let’s try something different from your inane repetition of claiming to be ignored. What kangaroo density would lead you to say, in the interest of other species, it was time to cull?

I’m still waiting on your answer about pine plantation habitat too.

Adding to my points below about those opposing the cull being ignored, the Government has recently chosen to ignore a hard copy petition signed by nearly 860 people.

The petition was presented to the legislative assembly and the decision was that no further inquiry was required.

“…chosen to ignore a hard copy petition signed by nearly 860 people ”
So you lodged a petition (853 people) and it was rejected, like so many are on other topics.

However, they did not ignore it so to claim they did is a lie. The response is here:

Your problem is that you do not like the response, so by that you feel ignored.

From your petition, I am interested to know in what respect “pine plantations” (intended for commercial harvesting) should be considered natural habitat in Australia? Is your definition of diversity the different sizes of kangaroos?

They chose not to undertake further enquiries, so yes I would count that as being ignored.

Yes we get it. Unless you get exactly what you want, you are “being ignored”.

Similarly to other activists, no response that doesn’t give you exactly what you want would be adequate.

I already know you feel miffed, no need to repeat yourself.

Meanwhile I note that you skipped answering my queries entirely. You wholly ignored them, whereas the government responded to you, just neglected to agree with you and even discussed evidence to the contrary. Your response looks much like a tantrum .

Rebeccam1 has raised some very important points. Why is the ACT Government so resistant to long lasting, ongoing opposition to the killing of kangaroos in the ACT? Why do government MLAs fail to respond to very real concerns about the lethal treatment of an iconic native species that shares our environment? The decisions of MLAs about environmental issues should take genuine science into account, but of equal importance are moral and ethical considerations. It seems that most MLAs are barely thinking this through like intelligent human beings have a responsibility to do. How many of them are actually familiar with their own ‘controlled native species’ legislation? And how many of them are truly comfortable with it?

“Why is the ACT Government so resistant to long lasting, ongoing opposition to the killing of kangaroos in the ACT?”

You omitted either one of “majority” or “scientifically validated”. There are long-lasting, ongoing believers in all sorts of things without them being right except in their own view. Why should persistence alone make a view right?

Oh sure…I agree…there are some long lasting believers in a lot of things and that doesn’t necessarily make them right. I’m sure we could both list many such beliefs and attitudes, some of them promulgated by so-called experts of the day. The starting point that it is somehow acceptable to deliberately kill wildlife in its own habitat to solve a perceived problem in the minds of some humans is a long held belief of some in our society. More and more people are seeing the inherent injustice in this and find lethal control of animals in their habitat – especially when humans have caused any issues this may cause – reprehensible. When citizens in a democracy voice their genuine and well informed concerns, governments do well listen, rather than to simply dismiss any opposition to their position. They tend to ultimately get booted out if they don’t. I’m sure you can think of recent examples.

“it is somehow acceptable to deliberately kill wildlife in its own habitat to solve a perceived problem in the minds of some humans”
The first part is merely tendentious. For the second part, what else do humans do? So do other animals do all of it, by the way, just with less cogitation. Your comment is quite ordinary, probably not what you imagined when you wrote it.

“When citizens in a democracy voice their genuine and well informed concerns, governments do well listen, rather than to simply dismiss any opposition to their position”
And if the ‘genuine’ minority comments are not well-informed? Then the government would do well to listen, to compare with independent data and advice, then to dismiss the opposition with reasons. Guess what happened.

Since rebeccam1 seems not keen, perhaps you might explain to me the concepts of natural habitat in relation to harvestable pine plantation monocultures?

When I read your petition, I was quite disappointed in all of it. I had expected a better case.

If that is the case then why did the last two independent reviews (eg CSIRO) find that the cull was unnecessary? Oh btw, Putin says hello….

rebeccam1, I am always delighted by new and better information to evaluate. If you will show here the specific references on which you rely then I promise to read and consider them.

The ACT Government’s approach to the cull is bordering on dictatorial. I find this very disturbing.

Anyone who questions the need for the cull is ignored or stone walled. This has been the case for over ten years now.

Anyone who writes to the Government about the cull receives the same standard set of approved words that they trot out.

Government MLAs refuse to meet with anyone who wishes to discuss the cull, (other than one Labor MLA to date).

The ACT government doesn’t give the public the full picture of the cull and its impact. For example, they don’t disclose the numbers of joeys that are killed each year, or the cruel manner in which they are killed (bashed on the head etc).

We are taxpayers who are paying their salaries, and for the cull program.

They are accountable to US.

“They are accountable to US.”

“US” is more than 853 petitioners on a Canberra-wide well-studied and argued issue so, yes, they are taking appropriate account.

The government is accountable to ALL tax payers, therefore their actions and decisions should be open and transparent.

That they are accountable to all voters was very much my point. You are part of a small minority and still they have taken the trouble to respond to you, accounting for their decisions. Worthy of applause, don’t you think? Oh, no, you don’t.

The Environment Directorate’s table above states that there are 2,770 kangaroos on Mt Ainslie/Mt Majura. Could the Directorate please tell us where, on these reserves, such large numbers of kangaroos may be found? Regular walkers on these reserves are reporting seeing ‘none’ or a ‘few’. Searches conducted by citizen scientists over all segments of the reserve, including in steep wooded terrain where there are very few (not preferred habitat) are finding nothing like these numbers. If the Directorate is confident of their population estimates then they should have some idea of the locations where they can be found. We’d like to think your numbers are correct. So, where are they, please?

It’s worth pointing out that ‘ecology’ as some comments use it is a misnomer for the ‘science’ that the ACT Government and many graziers rely on. What inhabits the ACT policies is a wildlife program that is taught at the University of Canberra and elsewhere of applied ecology … introduced to Australia with colonial settlement to support agricultural industries. A basic idea and goal of applied ecology is ways to ‘manage’ ie remove or kill (now with a commercial skin and meat trade– the world’s biggest onland wildlife slaughter), inconvenient native animals that might interfere with profit and development. There is almost no true ecology in the ACT’s view of kangaroos ( or dingos, or maybe wombats as far as I can tell). That would require doing some baseline research on the ecological role of these animals in grassland and woodland ecosystems. Pretty well totally lacking in Australia

Controversies about wildlife management are not unusual in western democratic countries. Dispute with wildlife counts by scientists is almost always a key feature. Wildlife controversies are rarely able to be resolved agreeably because the contest is between ecology (a complex science) and a mix of under-qualified armchair experts and people with quasi-religious opposition to the killing of appealing types of animals, often referred to as ‘sentient’. People in the latter group often attempt to argue from a scientific perspective, but do so ineptly, such as providing alternative counts obtained by methods that have no scientific basis. Wildlife controversy has a lot in common with better known anti-science controversies such as opposition to vaccination and denial of anthropogenic climate change.

Aisha Bottrill8:37 am 06 Oct 22

Firstly – direct counts are a scientific method and is a method used by the ACT Government ecologists. They just only use it in some reserves and prefer walked line transects due to “time and resource constraints” (Conservator said this). Luckily, citizen scientists are a fairly large group and cover whole reserves over a weekend using the direct count method. Secondly – you’re happy to throw out insults but won’t even put your name to it, so brave haha!!

Yes direct counts can be a scientific method of counting but that’s not really what your “citizen scientists” (really anti-cull activists) are doing.

Aisha Bottrill12:07 pm 06 Oct 22

The citizen scientists have done a direct count. Why are you suggesting that’s not what they have done?

“Why are you suggesting that’s not what they have done?”

Because they have not engaged in the actual scientific methods of how direct counts should be completed with any rigour to gain a reasonably accurate result. And they clearly ignore any information that does not suit the intended outcome of what they and you are trying to achieve.

The funny thing is that you’re so hopelessly biased that you truly can’t see it.

But anyway, I just went for a walk in my local nature reserve and when I closed my eyes, I couldn’t see any kangaroos either. Perhaps I should add the “data” to your burgeoning “scientific research”?

Direct count is a recognised scientific method. Volunteers have spent hundreds of hours of their personal time to undertake the counts which is far more effort than the Directorate which relies on formulas, extrapolations and dodgy desk top analysis.

I find it really disturbing that you think residents don’t have the right to question “the science”. We are paying for this program after all, aren’t we?

Supposedly we are living in a democracy however YOU and the ACT Government seem to think that residents should shut up and be ignored.

Scientists are not infallible. They make mistakes like everyone else.

Wasn’t it scientists who thought bringing cane toads to Australia would be a great idea? How did that turn out?! I could go on.

If the Directorate is confident that it is doing the right thing, it should welcome public scrutiny and should operate in a transparent and open manner.

The previous two independent reviews of the program found that the cull was NOT NECCESSARY. Eight years later, thousands of kangaroos and their joeys have been killed, in a manner which most Canberrans would find sickening.

It’s no co-incidence that the Directorate has avoided an independent review since the CSIRO. They obviously want to avoid scrutinyand to be found to be doing the wrong thing.

Clearly, the Directorate are hell bent on killing kangaroos.

If the research undertaken by citizen scientists is invalid, then why do scientists ask citizen scientists to count bogong moths, koalas, playpuses

”…. which is far more effort than the Directorate which relies on formulas, extrapolations and dodgy desk top analysis.”

Vladimir rang. I think he has a job offer for you in Special PR Operations

Rebecca, to your 5:12 pm post, can you not imagine the difference?

Scientists are happy to ask citizens to make observations when it is reasonably likely that their responses will be unbiassed. Even so, the data volume needs to be high with cross-comparisons or statistical adjustments done to try to spot and reduce bias which will occur in uncontrolled data collection by amateurs.

If the observer is known by some means to be biassed, their data should be discarded, or down-weighted if there is an adequate means.

If an observer shows unadjusted bias, in fact is a campaigner, then one can be equally clear about paying little regard to their observations when better are available.

Now do you see the difference?

You mentioned elsewhere feral horses. There are colour and context differences between you and feral horse defenders yet both of you ultimately favour environmental damage to protect your pet cause. You are just the same.

Video-recording drones can systematically survey reserves at various spectral frequencies, including infrared. The recordings can be analyzed for kangaroos using latest image analysis software and re-analyzed with improved software in future. Locations of kangaroos will be ground truthed and kangaroo densities can be evaluated against hyperspectral images of grass and forest cover. Objective, repeatable, fast and cheap methods like these are used in other jurisdictions for, among other, counting koalas. The dinosaurs at the directorate are wasting resources and funds on disputable, outdated, methods that have little more usage than deniability, mostly implausible, of counts by others.

That technology does work with objects like koalas that move little in the time taken for the drone to image the entire site, which is likely to be one or a few hours. It works less well for objects below the tree canopy because the counted object, eg kangaroo or koala has to be identifiable from other items and in many areas there is a surprising amount of hot rocks and other false objects to be eliminated. For mobile species like kangaroos, and species that live mainly under the tree canopy rather than in it, it is still unproven. After many years, ACT trials have yet to provide convincing results. But one day it is likely to be a good method

Time taken to survey can be minimized by using an array of drones working in tandem. Identification can be improved by using a second array in tandem with the first array but flying at a different height and/or using a difference lens angle. Hot rocks can be avoided by flying around dawn. Machine learning techniques can reduce other false objects.

crappicker, what is your experience with using thermal imaging drones for purposes of formal science? Have you significant experience interpreting thermal images at all?
What is your experience managing “an array of drones working in tandem [sic]” and with what results?

Still, since you are here and keen to talk, perhaps you could answer the questions being avoided by rebeccam1 and Motojohno. You will find them scattered around here.
Particularly, what kangaroo density would lead you to say, in the interest of other species, it was time to cull?

A pattern particularly striking here is the hopelessly non-scientific behaviours of the kangaroo zealots (a fair word given their expressed rejection of any answer but their own). What credibility is owed to those who make absurd claims which they refuse to explain or defend, or adopt positions with explicit bias and arbitrary rejection of alternatives, or claim supporting research which they then hold secret, or attack actual research by saying “my mate and I took a walk in the park and reckon your formal research is all wrong”. In the context of asking justification of actual research, these behaviours are rankly hypocritical. They are also speciesist in their willingness to advantage kangaroos over anything else. Silly.

Is that just your theoretical opinion crappicker, or can you provide examples published in reputable science journals please, of wildlife counts actually carried out successfully in the manner you describe, preferably ones that were evaluated against other count methods. (I know of published examples for slow moving upper canopy animals like Oranutans and Koalas and there are thermal counts of large-bodied birds sitting on nests in the open, but I mean counts of things like kangaroos, white-tailed deer, etc that can move rapidly at ground level below trees, not just out in the open.)

No reply from crappicker!!
In this comment thread, crappicker began by referring to the government scientists (who have had their count methods reviewed more than once by independent experts) as ‘The dinosaurs at the directorate …. wasting resources and funds on disputable, outdated, [count] methods’. According to crappicker the proper count method uses ‘an array of drones working in tandem ….(with) …. a second array in tandem with the first array but flying at a different height and/or using a difference lens angle’. Unsurprisingly, Crappicker was unable to provide any real world evidence to support these claims. That would be partly because this wildlife survey method exists only in crappicker’s imagination. Now what was that statement again, about wasting resources on count methods?

Arrogant. Rude. Completely lacking in relevant experience. Wrong. Crappicker is typical of a high proportion of the people who criticise science-based programs, including wildlife management programs like the kangaroo cull. Its ignorant and its unAustralian.

However, in the main this thread has been surprisingly different to the normal commentary on science-based programs, with little of the rudeness I have often seen. Well done Ken Beherns!

Hmmm, so we have scientific counting methods, peer reviewed and completed by professional ecologists with no real position other than wanting the best overall environmental outcome


Personal counts by individuals who are part of an activist group with stated desire to end the cull of kangaroos in the areas.

I can’t possibly think which one I would believe is more accurate. Very difficult indeed.

The ACT Government’s ’s alleged science was exposed as nonsense during the 2009, 2013 and 2014 ACAT hearings, and in numerous well-researched submissions submitted (and all ignored) during what the government called “public consultations” on the 2010 and 2017 Kangaroo Management Plans.  The CSIRO Plant Industries Report in 2014 confirms the expert opinion expressed at those hearings:
1. that kangaroos on ACT reserves do not damage the environment;
2. that the reserve ecosystems are healthier where up to three kangaroos per hectares are present; and
3. that more than three kangaroos per hectare could not be found on any of the reserves where data were collected.  And yet against all this evidence the ACT Government has continued killing kangaroos at an enormous scale every year.

None of what you just claimed is remotely true.

You’re attempting to cherry pick evidence that you think supports your view even though that CSIRO report does not find what you say it does and they specifically outline the limitations of their work and what it does not cover.

There is also mountains of research outlining the benefits of the culls to both flora and fauna biodiversity both in the ACT and across the country, but seemingly you want to ignore it because it doesn’t support your predetermined position.

There are legitimate scientific arguments to be made on exactly how much Kangaroos impact the environment and what the ideal populations and cull amounts should be.

But these attempts to claim that there are no negative impacts and that there aren’t really that many Kangaroos anyway are extremely shallow and self serving.

Where are these “mountains of research”? Put up or shut up. Really self-serving – haha! What I am getting out of it! On the other hand the ACT Government is getting money from developers to clear kangaroo land and replace it with grim cold concrete urban sprawl.

The government links the research on their website and its been a part of all the reports, hearings and consultations that you’ve already mentioned among others. There’s no point linking it all again, because you’ve clearly already ignored it for years.

And now reading your other comments, your position becomes even stranger. What on earth do Kangaroo populations have to do with the government developing the land for houses?

They aren’t a protected or endangered species, they hold little environmental value individually so the government doesn’t need to do anything with them if they want to develop the land. They would just do it.

Perhaps you could explain what you possibly could mean?

In fact, if the government actually wanted to do as you suggest, allowing the kangaroos to overpopulate the areas and destroy the actual biodiversity would be far more advantageous to that end.

It’s literally the reason that large tracts of land have been developed in recent decades because they were previously used as grazing land that destroyed any remnant environmental values that existed.

What do you think citizen scientists have to gain out of this exactly?

First of all, the ACT Government has only sought “scientific” advice from a small cabal of “applied” ecologists.  Applied ecology is a subset of the agricultural science and is distinct from actual ecology or wildlife science.
Secondly, the ACT Government engaged a New Zealand company to “peer review”its Kangaroo Management program. This company makes its money from killing wildlife, and whose “consultants know nothing about Australian wildlife, instead of nationally recognised experts.
Thirdly, more than two thirds of the public submissions regarding the draft Kangaroo Management Plan (KMP) 2017 opposed the killing of kangaroos.  No changes were made to the draft document as a result of any of these submissions before it became a legislative instrument.
Below are some examples of developments over the last two decades that have destroyed remnant off-reserve wildlife habitat adjoining or close to the Reserves, and further isolated the reserves from each other:
the suburb of Googong which appeared after the ACT government’s 2004 “cull” on the Googong Dam Reserve (this is in NSW, but managed by the ACT government);
the suburb of Lawson which appeared after the 2008 “cull” at the Belconnen Naval Transmission Station;
the suburb of Throsby which backs onto Goorooyarroo which is routinely “culled”;
the suburb of Crace which backs onto the Crace Grasslands which is routinely “culled”;
extension of the industrial suburb of Hume, near the East and West Jerrabomberra Nature Reserves, both of which are routinely “culled”;
the Molonglo development which backs onto Kama Nature Reserves which is routinely “culled”;
the Arboretum which closes off movement by wildlife living on Mt Painter and The Pinnacle Nature Reserves, both of which are routinely “culled”;
the extension of Mugga Lane Tip near Isaacs Ridge, Mount Mugga Mugga and Callum Brae Nature Reserves, all of which are routinely “culled”;
the extension of the Mugga Lane Quarry near Isaacs Ridge, Mount Mugga Mugga and Callum Brae Nature Reserves;
a private crematorium proposal for land that backs onto Callum Brae Nature Reserve;
the Long Gully Solar Farm on the Rose Cottage Horse Paddocks (which has been “culled”) near Wanniassa Hills Nature Reserve which is routinely culled;
the proposed Southern Memorial Park and new cemetery on the Rose Cottage Horse Paddocks near Wanniassa Hills Nature Reserve;
yet another proposed housing development at Red Hill (where tame and trusting kangaroos are being slaughtered, as part of the mass slaughter, across the CNP for the first time this year); and
the Majura Parkway and the Majura solar park backing onto Mount Majura Nature Reserve.

The fact that in the 13 years since the annual slaughter began, the “cull” has proved nothing.  An independent review has never been undertaken to determine what, if anything, the killing has achieved, nor what damage it has done.  No assessment has been undertaken to determine whether the program is value for money, or has met its purpose or whether it is being measured against performance criteria.  Nor has the ACT Government assessed the changes in grass biomass or ecosystem biodiversity over time.

Citizen scientists have nothing to gain.

Anti cull activists on the other hand have plenty.

There’s lots of the latter involved, very few of the former.

1. So you agree the science exists now, but you want to discredit the actual scientists becaise they don’t agree with you. Do better.

2. Is similarly meaningless.

3.Yes, there were a lot of public submissions from anti cull activists, not sure why you want their voices to be more important than actual scientists. Particularly when in your first point, you want to complain that these scientists are biased. What on earth do you think the anti cull activists are? It’s the same reason their “citizen science” is bunk, they don’t want to see the kangaroos and so they don’t count them.

As for the rest of your comment, correlation doesn’t equal causation. Those developments would have happened regardless of the presence or absence of kangaroos. There is no legislative lino to kangaroos existing in an area and development not being allowed.

To disprove your point, I can also similarly name dozens of areas where kangaroos are culled where no development has happened, nor where it can ever happen due to other actual environmental constraints. You’re tilting at windmills.

As for your last point, I agree that regular monitoring and reporting on outcomes should be done. But if you’re being honest with yourself, you know you aren’t really interested in the effectiveness of the cull, you’re looking for excuses to have it stopped.

Chewy, what do anti-cull activists have to gain? You’re making some silly and inaccurate assertions.

What have anti cull activists got to gain, aside from stress, trauma, heart ache, distress and PTSD?

What do anti cull activists have to gain?

Surely you couldn’t have written that with a straight face?

They want the culls to end.
By claiming there are less kangaroos in the area than the government claims, they think it provides evidence that:

1.The government is culling too many kangaroos and should stop.

2. The kangaroos couldn’t possibly be doing environmental damage because there isn’t very many of them.

3. The government’s evidence and science is discredited undermining the backing of the cull.

Surely no one is as dense as this. Their bias and motivation is as obvious as a flashing neon sign and identical to tactics used by similar activists elsewhere such as around Brumby culls in national parks.

Plenty to gain? Please explain.

So how does the end of the cull benefit those opposed to it exactly?

Are you seriously asking how people gain from getting what they want?


So Chewy, this is not really making much sense. Anti-cull citizens want the cull to stop for a range of reasons such as …. they don’t believe kangaroo populations in Canberra nature reserves are ‘overabundant’ as claimed by the Environment Directorate, they may think the methods and actions of ‘culling’ are inherently cruel to the animals being targeted, they may have serious concerns about animal welfare, they may think kangaroos are being made scapegoats for actions by humans (eg development of urban sprawl etc), they may think there are more humane solutions if ever there are population density issues eg during drought, they may think it’s a waste of tax payers’ money….and so on. So, if the ‘culls’ were to cease, what would anti-cull citizens gain? No more than a sense of relief that it’s over. Would you begrudge them that?

The problem being none of those concerns have much merit and stopping the cull would cause further environmental damage to other native flora and fauna in the areas.

So yes, I would begrudge placating their illogically grounded feelings because of the real world damage that doing so would cause.

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