24 January 2017

Bettongs fall prey to foxes in risky trial release

| John Thistleton
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Caption: an eastern bettong asleep. Photo: ACT Government.

At least 11 rare eastern bettongs have died in a contentious trial release into the Lower Cotter Catchment that raises questions on use of land management resources.

Fifteen bettongs remain alive. Four have been confirmed as killed by foxes, one from a bird of prey, and forensic results are yet to determine other deaths.

One has been returned to captivity with a faulty collar, while another one could be in the wild with a faulty collar. The collars monitor the endangered species three times a week.

The ACT Government will not say how much additional money is being spent on intensive fox control.

Environment Minister Mick Gentleman has not answered questions on the trial. A spokesman says he is on leave.

Two years of intensive control preceded the release phases, which began last spring. A wider variety of baits are being put out as fox cubs leave their families and begin to hunt.

Critics say the trial is futile because foxes will never be eradicated from the bush.

An environment and planning department spokesman said establishing bettongs at Tidbinbilla Nature Reserve and Mulligans Flat Woodland Sanctuary allowed greater risks to help lift the conservation status of the entire species, and improvements in future releases.

He said bettongs had not lived on the mainland for 100 years, and information from the trial would answer whether they could survive in fox-controlled areas, or if they would disperse away from the release-site.

He said the Lower Cotter trial met International Union for Conservation of Nature guidelines.

“There is no specific target population for this trial release because the main objective is garnering information, not establishing a population. If a full reintroduction is considered feasible, the number of animals to be released – and required predator control – would be determined based on the results of the trial including the area’s carrying capacity.”

Was the ACT Government right to release rare eastern bettongs in the Lower Cotter Catchment?

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Attempts to reintroduce rare species in the ACT have divided conservationists.

One critic said the Mulligans Flat sanctuary was a glorified zoo, while another has slammed the bettongs release, and suspects between 5 and 10,000 bettongs would be needed across the Cotter Valley and beyond to establish a viable population.

“Intensive fox and cat control would be required forever over the whole of the area plus a buffer zone around the bettong-occupied area. This would be huge and prohibitively expensive and require many staff,” he said.

In the spring of 2009, 43 vulnerable brown treecreepers caught from an established community south east of Wagga Wagga were released at Mulligans Flat and neighbouring nature reserve Goorooyarroo.

Although the countryside had been fortified with dead timber and artificial shelter areas, it did not provide the little insect-eaters with as much cover as the landscape from where they had been caught. Consequently other bigger predators quickly had an easy meal.

In 2014, 11 bush stone-curlews were brought into Mulligans sanctuary from where six escaped and were either taken by predators, probably foxes, or left the area.

Last year eastern quolls arrived at Mulligans from Tasmania and a private breeder in Victoria. Seven of them wasted no time scaling the 1.8 metre high fence and escaping. Foxes killed four of them, after which the fence was to be retrofitted.

In 2015 University of Canberra researcher Dr Bruno de Oliveira Ferronato published findings of reptiles being caught in the fence enclosing Mulligans sanctuary.

Over 16 months he found 108 reptiles had died and more than 1000 animals blocked at the fence, with eastern long-necked turtles accounting for almost all deaths.

Pictured above, an eastern bettong asleep. Photo: ACT Government

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Steve Chivers said :

Tadanus said :

Steve Chivers, the ACT government only made the media release in December because the journalist had asked a series of questions about the program which up until then had been secret. The media release was an attempt to put the program in a good light. As for your comment that I am using high sounding scientific language to criticise the program, that is a ridiculous comment. You would do better in discussing and refuting genuine scientific reasoning rather than resorting to attacking individuals just because they do not accord with your views. Of course I realise that it is a trial and that 30 animals is not enough to establish a wild population. However, what I argue is that if the scientists had done their background literature research and modelled the likelihood of success against the accepted IUCN criteria for translocations they would know that the chance of establishing a self sustaining population of bettongs in the wild in the ACT is zilch. Very substantial ACT community resources (several staff for two years for the fox control alone) have been committed to the program. Many of these resources have been drawn from other ACT P&C operational areas which have had to reduce their programs as a consequence. It is a mater of determining where resources are best spent for the best return for conservation. Putting significant resources into a study which a review of past literature on the issue and undertaking a basic risk assessment against accepted criteria would show that it was a waste of resources. I strongly suspect that the operational areas that had to provide resources from their programs would agree. To me it looks like a few scientists are indulging themselves in their interests to try and get a few publications rather than having a sincere concern about conservation in the ACT. After all substantial ACT community financial and other resources are being committed to this work. The community has a right to know and to seek justification for their use of these resources from those running the study.

Ok, fair comment. The PhD thesis by William Batson (available via GoogleScholar search) for the Mulligans and Tidbinbilla programs seems to have significant consideration of the IUCN criteria, however I wasn’t able to find any literature regarding whether this carried through to the LCC release. There is a point to be made about transparency of the LCC release, but I think condemning the scientists involved without involving them in the discussion is unfair.

Okay Steve, very happy to have a serious scientific debate with Professors Adrian Manning and David Lindenmayer. Where are they?

Steve Chivers6:52 pm 30 Jan 17

Tadanus said :

Steve Chivers, the ACT government only made the media release in December because the journalist had asked a series of questions about the program which up until then had been secret. The media release was an attempt to put the program in a good light. As for your comment that I am using high sounding scientific language to criticise the program, that is a ridiculous comment. You would do better in discussing and refuting genuine scientific reasoning rather than resorting to attacking individuals just because they do not accord with your views. Of course I realise that it is a trial and that 30 animals is not enough to establish a wild population. However, what I argue is that if the scientists had done their background literature research and modelled the likelihood of success against the accepted IUCN criteria for translocations they would know that the chance of establishing a self sustaining population of bettongs in the wild in the ACT is zilch. Very substantial ACT community resources (several staff for two years for the fox control alone) have been committed to the program. Many of these resources have been drawn from other ACT P&C operational areas which have had to reduce their programs as a consequence. It is a mater of determining where resources are best spent for the best return for conservation. Putting significant resources into a study which a review of past literature on the issue and undertaking a basic risk assessment against accepted criteria would show that it was a waste of resources. I strongly suspect that the operational areas that had to provide resources from their programs would agree. To me it looks like a few scientists are indulging themselves in their interests to try and get a few publications rather than having a sincere concern about conservation in the ACT. After all substantial ACT community financial and other resources are being committed to this work. The community has a right to know and to seek justification for their use of these resources from those running the study.

Ok, fair comment. The PhD thesis by William Batson (available via GoogleScholar search) for the Mulligans and Tidbinbilla programs seems to have significant consideration of the IUCN criteria, however I wasn’t able to find any literature regarding whether this carried through to the LCC release. There is a point to be made about transparency of the LCC release, but I think condemning the scientists involved without involving them in the discussion is unfair.

Steve Chivers, the ACT government only made the media release in December because the journalist had asked a series of questions about the program which up until then had been secret. The media release was an attempt to put the program in a good light.

Of course I realise that it is a trial and that 30 animals is not enough to establish a wild population. However, what I argue is that if the scientists had done their background literature research and modelled the likelihood of success against the accepted IUCN criteria for translocations they would know that the chance of establishing a self sustaining population of bettongs in the wild in the ACT is zilch. Very substantial ACT community resources (several staff for two years for the fox control alone) have been committed to the program. Many of these resources have been drawn from other ACT P&C operational areas which have had to reduce their programs as a consequence. It is a mater of determining where resources are best spent for the best return for conservation. Putting significant resources into a study which a review of past literature on the issue and undertaking a basic risk assessment against accepted criteria would show that it was a waste of resources. I strongly suspect that the operational areas that had to provide resources from their programs would agree. To me it looks like a few scientists are indulging themselves in their interests to try and get a few publications rather than having a sincere concern about conservation in the ACT. After all substantial ACT community financial and other resources are being committed to this work. The community has a right to know and to seek justification for their use of these resources from those running the study.

wildturkeycanoe12:54 pm 30 Jan 17

Maryan said :

Why don’t we just change the rules & let people keep them as pets. Have dogs or cats ever become endangered? Or ferrets? or budgies? or cockatoos? or mice?
Just a thought . . .

I was going to suggest something similar in my last post, perhaps an “Adop-a-Bettong” program. The only thing that would make it difficult is providing the right dietary requirements and preventing escape from the backyard. I think such a plan would definitely help increase the population/prevent extinction and would be welcomed by Canberrans. Getting them to survive in the wild is a different story though. Without native parents to teach the young what is good to eat and how to evade predators, the species would become so domesticated they’d probably not survive in the wild.

Steve Chivers12:50 pm 30 Jan 17

wildturkeycanoe said :

Steve Chivers said :

This was a “trial”, an experiment… gathering data before making a determined attempt at reintroduction. They likely wanted to gather data on predation and survival rates.

So, putting them in an area that isn’t suitable because of predators and future climate change, helps them get data on the success of introducing them into a completely different alpine area with a different concentration of predators, both native and introduced? They might as well have just put them in a giant blender and seen how many survive, the data would be just as useful.

Who said they only plan on reintroducing them to alpine environments? No not the researchers themselves, just another commentator on this article. The plan is to re-establish them in their former habitat, which includes from southeastern QLD to southeastern SA, not just alpine environments.

Steve Chivers12:36 pm 30 Jan 17

John Thistleton said :

My biggest problem with this trial is that it was never established in public. It came to light because someone blew the whistle to alert the wider Canberra community. We often see our ACT pollies with newly arrived rare native animals. I am still waiting to see one of them endorse this trial, which is being undertaken in an extremely prone bushfire zone….not to mention foxes.

It was established in public, unfortunately people like to create conspiracies because it creates drama:

http://www.cmd.act.gov.au/open_government/inform/act_government_media_releases/esdd/2016/eastern-bettongs-go-beyond-the-fence

Steve Chivers12:33 pm 30 Jan 17

Tadanus said :

Steve Chivers said that do you really believe that the ANU scientists had not considered these matters before commencing the experiment. If they have please point me to the reports. I have listed a number of factors that should have been considered before releasing the animals. These are based on my knowledge of the translocation literature and the IUCN criteria for reintroductions. If the ANU scientists had undertaken a critical assessment of the study against the IUCN criteria and reviewed the relevant literature they would know that the chances of establishing a self sustaining wild colony of bettongs in the LCC is zilch. Just for example consider a Population Viability Assessment of the bettong population that would be required to withstand predation and other factors, The size of such a population, the area it would need to cover and the cost of extensive and ongoing predator control alone that would be required (but wouldn’t be sufficient as shown by numerous studies in peer reviewed journals) would be prohibitively expensive and impracticable. This alone would show the futility of the study. If you can post or point out that such an assessment had been done then I would appreciate it.

This was not a one-off attempt at establishing a self-sustaining population. Would an ANU Professor really believe a population of 28 bettongs in the wild would become self-sustaining? This was a trial experiment to gain some level of understanding of how difficult it may be to establish bettongs on the mainland again. The main project is still Mulligans Flat, which has been a huge success, over 200 bettongs now from a pop of an introduced pop around 30, and at Tidbinbilla the pop is up to around 70 now from a similar sized original pop. With the success of the breeding program, and that the government is willing to fund the project, the research group ‘tested the water’ in the beyond the fences of Mulligans. Do you jump straight into a hot bath? No you put your little toe in first to see what happens. As far as I know, depending on the success of this initial wild-release, more bettongs may be released to bolster the population.

And for those who think this was some kind of ‘secret’ government release, the ACT government did a media release in December last year when the LCC trial began:

http://www.cmd.act.gov.au/open_government/inform/act_government_media_releases/esdd/2016/eastern-bettongs-go-beyond-the-fence

Maryan said :

Why don’t we just change the rules & let people keep them as pets. Have dogs or cats ever become endangered? Or ferrets? or budgies? or cockatoos? or mice?
Just a thought . . .

Ferrets, are not native animals and they have to be licensed to keep as pets in the ACT. It’s the same with dogs (and cats?). Trout are also introduced and revered even though they compete with many species of native fish.

But I agree bettongs would probably make good pets and they would have a good measure of protection in a domestic environment.

Why don’t we just change the rules & let people keep them as pets. Have dogs or cats ever become endangered? Or ferrets? or budgies? or cockatoos? or mice?
Just a thought . . .

wildturkeycanoe6:31 pm 28 Jan 17

Steve Chivers said :

This was a “trial”, an experiment… gathering data before making a determined attempt at reintroduction. They likely wanted to gather data on predation and survival rates.

So, putting them in an area that isn’t suitable because of predators and future climate change, helps them get data on the success of introducing them into a completely different alpine area with a different concentration of predators, both native and introduced? They might as well have just put them in a giant blender and seen how many survive, the data would be just as useful.

Steve Chivers said that do you really believe that the ANU scientists had not considered these maters before commencing the experiment. If they have please point me to the reports. I have listed a number of factors that should have been considered before releasing the animals. These are based on my knowledge of the translocation literature and the IUCN criteria for reintroductions. If the ANU scientists had undertaken a critical assessment of the study against the IUCN criteria and reviewed the relevant literature they would know that the chances of establishing a self sustaining wild colony of bettongs in the LCC is zilch. Just for example consider a Population Viability Assessment of the bettong population that would be required to withstand predation and other factors, The size of such a population, the area it would need to cover and the cost of extensive and ongoing predator control alone that would be required (but wouldn’t be sufficient as shown by numerous studies in peer reviewed journals) would be prohibitively expensive and impracticable. This alone would show the futility of the study. If you can post or point out that such an assessment had been done then I would appreciate it.

Steve Chivers said :

wildturkeycanoe said :

I can not believe the “scientists” who ran this project couldn’t see this happening. There are foxes running around in the suburbs, so who knows how many are out in the fringes of Canberra. Releasing a defenseless little critter into areas that quite obviously contain large numbers of predators was always going to fail. Now they have to go and breed up a new batch of bettongs and try something else. Perhaps they are simply extending the duration of the project so that they have some job security, who knows. But any person with a bit of logic could’ve put money on this experiment failing. You may as well have dropped a spoon full of guppies into a bucket of pirhanas and seen the same result.

Do you really think the scientists didn’t foresee this happening? This was a “trial”, an experiment… gathering data before making a determined attempt at reintroduction. They likely wanted to gather data on predation and survival rates.

I’m surprised at the number of people who’ve read this minute media-release suddenly think they’re experts on wildlife re-introductions, having not even read any of the actual scientific reports by the bettong recovery team at ANU.

Why couldn’t they have used computer modelling instead?

It works for climate scientists.

Steve Chivers9:27 am 28 Jan 17

wildturkeycanoe said :

I can not believe the “scientists” who ran this project couldn’t see this happening. There are foxes running around in the suburbs, so who knows how many are out in the fringes of Canberra. Releasing a defenseless little critter into areas that quite obviously contain large numbers of predators was always going to fail. Now they have to go and breed up a new batch of bettongs and try something else. Perhaps they are simply extending the duration of the project so that they have some job security, who knows. But any person with a bit of logic could’ve put money on this experiment failing. You may as well have dropped a spoon full of guppies into a bucket of pirhanas and seen the same result.

Do you really think the scientists didn’t foresee this happening? This was a “trial”, an experiment… gathering data before making a determined attempt at reintroduction. They likely wanted to gather data on predation and survival rates.

I’m surprised at the number of people who’ve read this minute media-release suddenly think they’re experts on wildlife re-introductions, having not even read any of the actual scientific reports by the bettong recovery team at ANU.

wildturkeycanoe said :

Tadanus said :

. For example, bettongs feed on sub-surface fungi and invertebrates. These are certain to have declined as the soil became drier, a situation that will only get worse as global temperatures rise and effective rainfall declines.

So, why not try to reintroduce them to an area that is slightly higher in elevation and has the right climate for these little creatures? The lack of implementing an idea as simplistic as this astounds me. It’s like if your garden is not getting enough sun to grow tomatoes because you built a roof over it, why wouldn’t you plant them elsewhere in the yard that has ample light? Just like the fox problem, it isn’t rocket science, so how poorly is this government department run? I think they need some outside help, perhaps a local primary school?

That is great “thinking outside the square”.

Unless you are an “expert” (preferably from overseas), the agency will ignore your suggestions.

wildturkeycanoe4:28 pm 26 Jan 17

Tadanus said :

. For example, bettongs feed on sub-surface fungi and invertebrates. These are certain to have declined as the soil became drier, a situation that will only get worse as global temperatures rise and effective rainfall declines.

So, why not try to reintroduce them to an area that is slightly higher in elevation and has the right climate for these little creatures? The lack of implementing an idea as simplistic as this astounds me. It’s like if your garden is not getting enough sun to grow tomatoes because you built a roof over it, why wouldn’t you plant them elsewhere in the yard that has ample light? Just like the fox problem, it isn’t rocket science, so how poorly is this government department run? I think they need some outside help, perhaps a local primary school?

I note in the Canberra Times that a spokesperson for the ACT Parks and Conservation Service said that the trial is to learn more about the system for before establishing bettongs in the wild. From what I can see, the assumption is that foxes, dogs (read dingoes in the Cotter) and cats are the cause for the extinction of bettongs on mainland Australia. Just for a minute suppose that they are. It is not feasible or economically practical to control foxes, cats and dogs for the foreseeable future to the level necessary across the area that would be required to establish a viable population of bettongs in the ACT, as I said in my previous comment. Also, why control dogs/dingoes? I understood that ACT Parks considered them to be native and an important top order predator.
But worse, it is highly likely that other factors have led to the demise of bettongs on mainland Australia. Other peer reviewed studies in various parts of Australia have shown that fox control alone is not sufficient to conserve rare and endangered species. For example, while there was an initial recovery of native mammals from large-scale and intensive fox control over many years in areas such as Western Shield, Western Australia and Glenelg Ark, Victoria, despite intensive and long-term fox control, most mammals have returned to near pre-fox control levels. Also under the NSW Fox Threat Abatement Plan, only one program out of 20 that were aimed at conserving threatened species showed any recovery in response to intensive fox control. The one that did, the south coast shorebird recovery program, had some success because they addressed several factors such as suitable nesting habitat, tidal surge and predation by native predators, not just fox predation. It is very likely that other factors in addition to fox and cat predation have led to the loss of bettongs in the ACT. These are likely to be lack of suitable food and other resources, probably as a result of changed fire regimes and global warming as well as loss or degradation of habitat. For example, bettongs feed on sub-surface fungi and invertebrates. These are certain to have declined as the soil became drier, a situation that will only get worse as global temperatures rise and effective rainfall declines.
To justify the expense of the present study and the use and potential loss of such rare animals, it behoves scientists running the study first to identify all the factors that may explain and observation (loss of a species) and gather the available information to assess each cause. Those causes/factors that cannot be eliminated based on the available evidence need to be tested experimentally. This is the accepted basis of experimental design. I see no evidence that the current study is looking at factors other than predation.

Roksteddy said :

dungfungus said :

“fox-controlled areas”?

No such things exist.

Do you mean apart from Mulligans Flat?

That is a fox-free area – different thing.

dungfungus said :

“fox-controlled areas”?

No such things exist.

Do you mean apart from Mulligans Flat?

John Thistleton said :

My biggest problem with this trial is that it was never established in public. It came to light because someone blew the whistle to alert the wider Canberra community. We often see our ACT pollies with newly arrived rare native animals. I am still waiting to see one of them endorse this trial, which is being undertaken in an extremely prone bushfire zone….not to mention foxes.

Good points John.

I am waiting for the government to introduce more Rainbow Lorikeets to establish a resident population:
http://canberrabirds.org.au/birds/rainbow-lorikeet/

Then it could replace the less vibrant Gang Gang as the forna in our emblem.

John Thistleton8:45 am 25 Jan 17

My biggest problem with this trial is that it was never established in public. It came to light because someone blew the whistle to alert the wider Canberra community. We often see our ACT pollies with newly arrived rare native animals. I am still waiting to see one of them endorse this trial, which is being undertaken in an extremely prone bushfire zone….not to mention foxes.

wildturkeycanoe6:52 am 25 Jan 17

I can not believe the “scientists” who ran this project couldn’t see this happening. There are foxes running around in the suburbs, so who knows how many are out in the fringes of Canberra. Releasing a defenseless little critter into areas that quite obviously contain large numbers of predators was always going to fail. Now they have to go and breed up a new batch of bettongs and try something else. Perhaps they are simply extending the duration of the project so that they have some job security, who knows. But any person with a bit of logic could’ve put money on this experiment failing. You may as well have dropped a spoon full of guppies into a bucket of pirhanas and seen the same result.

The article is correct. The wild bettong population would need to be in the thousands and spread over a large are for the wild population to survive the ravages of drought, bush fires and predation from foxes, cats and native predators. Trying to control foxes alone over such a large area – forever – would be impractical and hugely expensive. Also as the article reports, displaying animals in a fenced enclosure is difficult and expensive and not without significant deleterious impact to local native wildlife. Maybe worthwhile but it would be interesting to see a cost benefit analysis of the program as well as a risk analysis.

We need another poll: Which is more fun? Working with cute and cuddly bettongs or eradicating foxes? Easy to guess which way the poll would swing, but this trial does seem to be putting the cart before the horse.

“fox-controlled areas”?

No such things exist.

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