Support sought for high-tech count of Kosciuszko's wild horses

Hi Philip of Narooma, so, both you and Galea lack ecological qualifications. In particular you both lack experience with the unusual and very learned statistical method of distance sampling. And it seems you have not read Galea’s report on the counting methods (18 pp). If you had, I suspect you may be less inclined to support her.

In fact the current count method IS published (https://www.jstor.org/stable/3784462). You’re correct that the 2022 report was not reviewed before release. But the earlier reports by Cairns are almost identical in nature, and have been extensively reviewed. After favourable reviews of previous reports I guess the NPWS and its minister did not want to delay the latest (2022) results while waiting for another review.

Even if doubts about the count were given credibility, and the count results were taken as merely an index of abundance, applying the same method consistently over 21 years shows that (1) the population increased steadily at 15% per year (in the face of control attempts); (2) by 2022 there were many times as many horses as when this method of counting commenced in 2001; and (3) that horses are now occupying a greater area.

Therefore many vulnerable animal and plant populations are encountering horses for the first time, or encountering high densities of them for the first time. Two scientific committees advising both the Commonwealth and NSW Governments have identified more than a score of such horse-vulnerable species, many of which occur nowhere but in Kosci NP. The clock needs to be turned back so those populations can survive even in the short term.

Ecologists have been warning about horses since at least 1953 and advising for decades on methods more humane than what was being used. If earlier advice from ecologists had been respected, we would not be in the current predicament.

“An ecologist’ .. it appears you are unaware of what a peer-review means. It is very different to a ‘report’, even a report that has ‘favourable reviews. Perhaps I could take you back to 2003 and the catastrophe of the Grey Nurse shark count.

This count, a ‘mark recapture’, was done using ‘correct’ statistical methods (according to the authors) and the report presented to NSW DPI (fisheries). Subsequently the GNS was declared ‘critically endangered’ by the NSW Threatened Species Scientific Committee. This diverted millions of dollars fisheries funds into efforts to ‘Save the GNS’. Along with several others a case was brought by the NCC and the counts veracity was shown to be wrong. Instead of a number between 300 and 500 the actual count is more than 2700.

What went wrong? Nothing was wrong as far as the science of ‘mark recapture’. What was wrong was the methodology of the count. In fact many felt there was a corruption of the process that has probably soured many off so called ‘ecological’ methods.

You are correct that I do not have ‘ecological qualifications’ (whatever they are?). I have found the only folks who hammer that point in an argument are new graduates (or undergraduates) with minimal experience in the field. Notwithstanding my degree in Veterinary Science and my post grad. Qualifications, my near 40 years experience in statistical methodology in both Australia and Africa means I adopt a cautious approach when trying to count any wild animal.

My principal concerns about the feral horse issue is the amount of damage they are alleged to do compared to pigs, wild dogs and rabbits. The horses have been present in KNP since the mid 1800’s. Since the mid 1950’s virtually no control method has been performed and the number is alleged to be 18,000. So what was the population in 1960 at your figure of 15% increase (per year)?

Phillip,
If your focus is mainly on the damage done by horses in KNP, why haven’t you mentioned the significant body of scientific evidence showing horses specifically causing significant damage?

Damage that is fundamentally different to that caused by other feral animals and thus distinguishable by researchers in the area? Or is that research also in question?

I’m also wondering what the potential inaccuracy in the horse counts matters for, in overall effect?

Are you worried about a misallocation of resources to control feral animals? Or something else?

The other feral animal types you mention are controlled using similar methods, with thousands of wild deer, pigs etc being shot using helicopters in recent years. Rabbit populations also face significant control measures.

Seemingly the only bad thing that would occur is that they remove too many feral horses which would then be reflected in subsequent population counts, even if with wider confidence bounds than desired. It would also become significantly more difficult to hit expected cull quotas if the counts are wrong to such a high level as claimed.

If the horses are not the culprits for the environmental damage (despite the significant body of evidence showing the opposite), surely the environmental surveys would then show continued degradation of the areas? Leading to a need to adopt other methods and controls.

But I’m struggling to see a real downside of managing the feral horse populations, regardless of the claimed error in the counting methodology. Obviously improving those methods over time would be beneficial, but it doesn’t seem to be a reason to stop culling the feral animals in the short term. Also noting that using inaccuracy of counting is a common method used by activists to achieve their preferred outcome and stop population control measures.

Again Philip of Narooma, since it seems to matter to you, I too have had over 40 years experience, not that there is anything necessarily wrong with the thoughts of recent graduates. Nor is there any basis for an experienced veterinarian like you to try to cast shade on ecology. As with veterinary science, ecology is a well recognised science. It is defined as the scientific study of the relationships that determine abundance of living organisms. And there are numerous journals publishing ecology such as the Australian ‘Austral Ecology’ and ‘Wildlife Research’.

Returning to the topic of horse counts, there are multiple papers in peer reviewed journals, including ones comparing different methods of estimating horse abundance and numerous scientists have been involved in one way or another, over 21 years since the current counting method was first deployed, so the horse counts are not comparable to a single mistaken count of sharks.

Also regarding impacts there are multiple papers from authors in different research institutions showing horse impacts greater than the other species you mention. But even if the impact of horses was less than that of something else, it would be no basis to refrain from acting to reduce the horse impacts. And as Chewy14 argues, all the other species are being subjected to control.

I think this conversation has got to a point it is not worth persisting with.

A summary of my concerns regarding the feral horse population
1. In KNP 4,500 deer, 670 pigs, 15 goats and 17 foxes were killed by aerial shooting in three years to end of 2022.
2. I have no qualms about reducing the number of horses if the following conditions are satisfied and correct.
a. The horses have been demonstrated to be the sole (even major) cause of the damage to the ecosystem , especially in the north of the park where they are most numerous. From personal observation their numbers are negligible
b. Consideration has been given to what will replace the horses. My concern relates to feral pigs, which are quite numerous in the north of the park. I don’t believe any thought has been given to this
3. Animal behaviour, of which I am very familiar, does not predicate that horses will convert stream and river edges to mud wallows, even cattle don’t. Pigs on the other hand are notorious for doing this. There may well be horse prints in a muddy area, in my opinion they did NOT do the original damage. Deer can be very damaging to river banks by the way the move over rough country – in single file. On our farm near Goulburn we were overrun with fallow deer at certain times of the year and caused erosion of Covan creek.
4. Weeds – AE claims the horses hoof means they carry weed seeds. I very much doubt that – horses can certainly pass weed seeds in their manure as they have a relatively simple stomach compared to a cow. But the weeds are already there, over the past 150 years!!
5. Carrying capacity. In terms of numbers of horses the concept that they will increase 15% year on year in a fixed environment (a very large paddock if you like) is completely foreign to animal husbandry and management. It is a furphy. Theoretically that is possible
However:
a. Any large animal Veterinarian drives around calculating the carrying capacity of a paddock in terms of DSE. In other words 1 DSE is a 50kg merino wether and 1 DSE to the acre is the feed required in one acre to maintain his weight for a year.
b. A horse is the equivalent of 10 DSE, a pregnant mare is about 15.
c. The northern part of KNP varies between 0.5 to 1 DSE per acre. In other words one horse would require between 10 to 20 acres acres to maintain his weight. The southern part (Byadbo and Tin mine huts) would be 0.2 to 0.5.

In my opinion the horse population has probably varied by 10 to 30% up and down over the past 40 years

“The ecologists think that their PhD qualifications, training, years of experience, and hard-won papers in peer-reviewed ecology journals give them credibility.”

Where can we go then if we can’t rely on all of this experience and knowledge An Ecologist?

Whoosh

You make me ashamed to be an aussie. All life is sacred. These horses were brought here by men and left alone in the inhospitable bush by men. They are a large part of our history and should be protected by law. If their numbers grow too large then vets should geld a number of the stallions. Problem solved. Aerial shooting is the most inhumane way to solve this or any other overpopulation problem. Not Acceptable to the Australian people.

You are embarrassing yourself. Horses are as welcome in a National Park as wild pigs, rabbits or cane toads. Most Australians support their total eradication.

Your argument appears to be that if men do something, even where it is damaging, that action should be protected by law.

Quite a few people might disagree with that weird attempt at logic.

“All life is sacred”
Nice to know your opinions are devout, though rationality has exited your cathedral..

It sickens & disgusts me that many more of these horses are, once again, going to be slaughtered by aerial shooting & left to die an agonising death, shot to pieces by gun toting rednecks, with no conscience, shame on you

Inaction has consequences, as surely as action. Choices are unavoidable, whatever your fantasies.

Some people are trying to fix the horse pollution in the Kosciuszko back yard. Kindly take your nonsense elsewhere.

No Nicole, humans evolved in Africa. They did not evolve in Australia. Aboriginal people also invaded Australia and contributed to the extinction of numerous species. Where should we defecate if not in the toilet? Where do you do it?