Endangered Australia – What are we doing?

The Thylacine or Tasmanian Tiger
Image from http://www.unexplainedaustralia.com

Australia as a nation has a lot to be proud of. Pristine beaches, beautiful bush land, the Great Barrier Reef and Uluru are a few things that come to mind.

Australia also boasts the highest mammal extinction record in the world.

That is something I can say, I am not proud of.

And it’s probably something many Australians aren’t even aware of.

Twenty seven mammal species have become extinct in Australia in the last 200 years – no other country in the world has had that many mammal extinctions.

The Tasmanian tiger, desert bandicoot and brush tailed bettong are just a few species which no longer exist.

David Keith is a professor of botany at the University of New South Wales and is one of the authors of the new IUCN threatened ecosystems red list. I spoke to him about why Australia is experiencing such dramatic extinction rates.

“Two things happened,” he said.

Brush tailed bettong
Image from http://www.kidscyber.com.au

“Firstly, domestic livestock were introduced in excessive numbers and a lot of the vegetation that was cover for native animals was destroyed. The second thing that happened was that foxes and cats were introduced.”

“So the combination of reduced shelter for those animals to hide from predators and the introduction of new predators that they weren’t used to, meant that a lot of those mammal species disappeared in a very short space of time and more so than anywhere else around the world,” he explained.

We have over 1,500 mammal, bird, reptile, amphibian and plant species threatened with extinction in Australia. The Federal Government has also listed at least 3,000 ecosystems that are facing extinction.

Professor Keith attributes the endangered status of many ecosystems to land clearing – the conversion of native bush to agricultural or industrial land.

“The vast majority of the causes and the threatening processes that are driving the loss of biodiversity are related to human activities in some way,” he said.

“South west and south eastern woodlands and native grasslands for example, are in prime agricultural zones of Australia’s food production.”

Marine and freshwater ecosystems such as the Murray-Darling Basin and its major tributaries are also at risk due to water exploitation.

“There are a lot of wetlands in those areas that are in quite a bit of trouble because the water is not coming to them in the same way that they once did,” Keith said.

“It’s also about regulating the use of water. In the context of Australia’s variable climate you have to recognise that every year is not going to be a wet year and we have to plan for that.”

Desert bandicoot
Image from http://www.freewebs.com

Australia is home to more biodiversity than any other developed country on earth. It is one of the 17 ‘mega diverse’ nations along with Brazil, South Africa and Indonesia.

The majority of Australia’s species are endemic, meaning they are only found in Australia. Once they are gone, they are gone for good.

Dr. Sarah Legge from the Australian Wildlife Conservancy believes we must take urgent action now to stop further extinctions.

“It would be heart‐breaking and internationally embarrassing if we were to stand aside and witness another wave of extinctions without making any effort to intervene.”

“We need to better understand the detail of what each native mammal needs to survive,” she said.

Professor Keith agreed, “If it is business as usual, we are in for substantial losses. There are a lot of things that are only just hanging on so unless some more corrective action is taken, we are going to lose those things.”

Is the government doing enough? Keith tells me they can always do more. He also believes that some of Australia’s legislation on land clearing is not as strong as it needs to be. There are a lot of loopholes in the legislation that can allow for some inappropriate land clearance and habitat loss.

“People are probably a lot more in the dark than they should be about the state of the environment because after all, their physical, mental and economic wellbeing is really dependent on the environment,” he added.

Perhaps the problem is that we don’t hear about these issues very much. Every night there is the report on the stock market. We don’t get once a week, we don’t even get once a month, for environmental matters.

Will kangaroos be hopping out of our future?

Image from http://www.smh.com.au

Did you know that Australia’s kangaroo cull is the largest land based, commercial wildlife killing in the world? And that this year alone, the federal government will permit over 5 million kangaroos to be killed for commercial purposes? I didn’t.

Australia began exporting kangaroo meat in 1959 and today the meat and skin of our national icon travels to over 55 different countries. The red kangaroo, eastern grey kangaroo, western grey kangaroo and common wallaroo are the four species currently harvested for commercial export across New South Wales, Queensland, Western Australia and South Australia.

Over the last ten years 28 million kangaroos have been killed for commercial purposes along with the by product of 8 million joeys.

President for The Australian Society for Kangaroos, Nikki Stutterby, believes the Australian people are being misled about the reasons for the cull.

“The Australian public has been conned into thinking that this industry is a necessity and is about reducing damage to farms and population control, but it isn’t,” she says.

“It is about profit and it is decimating our kangaroos.”

But it’s not just kangaroos. In the Northern Territory this year, up to 70,000 crocodiles will be wild harvested. Both the salt and freshwater crocodile are on Appendix II of CITES, which lists animals that may not be threatened with extinction now, but might become so unless trade in them is strictly regulated.  Polar bears are on this same list.

In Tasmania, 60,000 brush tail possums were killed for wild harvest and crop damage between 2012- 2013. I didn’t even know Tasmania had that many possums.

So why are we doing this to our native animals?

Apparently, we have too many. It is about population control.

However the Federal government’s ‘Commercial Kangaroo Harvesting Fact Sheet’ clearly states that – “Australia has undergone severe drought in recent years, and because the primary driver of kangaroo populations is rainfall, overall kangaroo numbers in Australia declined as a result.”

Ms Stutterby reiterates that kangaroos do cease breeding in drought to avoid overpopulation and starvation.

“Kangaroos are quite capable of managing themselves within the Australian environment and have done so for 50 million years.”

“Research shows that kangaroos can only increase at a rate of around 10% per year, and once they reach equilibrium with their environment their population will stabilise,” she says.

The government fact sheet states kangaroos have been harvested and monitored for more than 25 years, during which time kangaroo populations have demonstrated a “strong capacity to recover from the regular occurrence of drought.”

This is contrary to the fact all four species of commercially hunted kangaroo now have lower population numbers then 10 years ago.

So what is the risk?

“Most Australian native animals that were hunted commercially have been pushed to the brink of extinction,” Nikki Stutterby says.

“This includes our koalas that were hunted for their fur, most species of whales that were hunted last century commercially and the Tasmanian tiger.”

Before approving any management plans that allow for wild harvesting and exportation, the Australian Government has to consider the biology, population size and conservation status of the species.

At the present time, all four species of kangaroo subject to commercial harvesting are not listed as threatened species.

A study by Hacker et al (2004) found that the effect of harvesting kangaroo populations is strongly influenced by the harvest rate (how often you harvest) and the sex ratio of the harvest (whether you cull males or females).

They found that at a constant harvest rate of mainly females, the population would decline.

So is the cull and trade regulated to ensure this doesn’t happen?

Dr Sophie Riley is a senior lecturer in the Faculty of Law at the University of Technology, Sydney. She is also the co-chair of the Teaching and Capacity Building Committee of the IUCN (International Union for the Conservation of Nature).

“Trade in native animals is regulated by a licensing system, and in the case of kangaroos, there are national codes for the humane shooting of kangaroos and wallabies.”

“There are different codes depending on whether the hunting is for commercial or non-commercial purposes,” Dr Riley explains.

A (2012) study by Boom et al reports that government agencies do not inspect carcasses at the point of kill. “Without inspections it is impossible for agencies to ensure compliance with the Code’s conditions on killing dependent young and injured adult kangaroos.”

It also discovers that enforcement of these codes is sometimes undermined by a conflict of interest because these agencies are “responsible for promoting the welfare of kangaroos and supporting the commercial kangaroo industry.”

Dr Riley believes that the efficacy of regulation depends on why kangaroo hunting has been established in the first place.

“If it is to deal with a land management problem, then decision-makers need to consider whether culling is successful, given the fact that it has not significantly reduced kangaroo numbers,” she says.

“If it is to maintain kangaroo herds for recreational or commercial hunters then it appears to have succeeded on that point. However, in both cases, hunters need to adhere to the national codes that have as their objective animal welfare concerns.

“Are these being met?” she questions.

Boom et al (2012) states that data relating to the “compliance and enforcement of the commercial kangaroo industry is limited”. They also find that prosecutions rarely occur and where prosecutions have been successful, low fines are generally imposed.

“Australian’s are being robbed of their national icon and misled about the reasons for their ongoing slaughter,” Australian Society for Kangaroos, Ms Stutterby says.

“The Australian public has never been consulted as to whether they agree with their native wildlife being slaughtered. It has remained a dirty secret.”

What does the future hold for native animals? Will profit override animal welfare and conservation? Or will kangaroos and other endemic species continue to thrive?

As Steve Irwin once said, “There is no such thing as the sustainable commercial hunting of wildlife.”

De-extinction for dummies

Gastric brooding frog
Image from frogsaregreen.org

The possibility of the ‘de-extinction’ of animals such as the Tasmanian tiger, dodo bird and woolly mammoth is overwhelming. But is it actually possible? Even if the animal can be revived, what are the long term consequences? Can it ever be released back into the wild as if nothing had ever happened?

To bring an extinct species back to life inevitably blurs the line between science fiction and reality. The scientific community has been reeling over recent breakthroughs in the ‘de-extinction’ field and the media has taken the opportunity to tell the public that it is indeed possible to resurrect vanished fauna from around the world.

One project to hit the headlines recently is the ‘Lazarus’ project, led by Professor Mike Archer from the University of New South Wales.  For the last two years, Archer and his team have been attempting to revive the extinct genome of the Gastric brooding frog (Rehobatrachus silus). The species was endemic to Australia and has been extinct for nearly 30 years.

When the news broke that the team had successfully revived an embryo loaded with the Gastric brooding frogs DNA, the media went into a frenzy proclaiming ‘extinct frog brought back to life’ and ‘bizarre frog back from the dead’. However many articles forgot to mention one critical part – the embryo (not frog) only survived 36 hours.

While the ‘Lazarus’ team is still pushing on with their work and are yet to revive a tadpole, Archer believes it is vital that efforts are made to recreate something humans potentially destroyed.

“The Gastric brooding frog is a species that it would appear has become extinct because of our indirect actions, probably from spreading the chytrid fungus,” he says. “So there is a moral or ethical issue here.”

Besides the moral implications of these endeavours, there are multiple practical hurdles that need to be overcome before we can proclaim we have ‘played god’ and brought an entire organism back from the dead.

In order to revitalise a genome or animals DNA, you must first have access to it.

Due to the previous work of scientist Mike Tyler on the Gastric brooding frog, Mike Archer has access to two entire frog samples that can be used for DNA extraction.

“We actually have a number of individuals that were frozen, so there is genetic variation available. We wouldn’t be looking to mass produce the same individual we would be using different body cells,” Archer says.

Unfortunately, for most other species on the resurrection list, their DNA is missing or too fragmented to use.

Conservation geneticist, Professor Richard Frankham from Macquarie University explains that it is technically very difficult to revive an extinct species.

“It is probably impossible in the near future due to the poor preservation of species DNA,” he says.

So why do we need lots of DNA?

Low genetic variability (the amount of DNA in a species gene pool) has been shown in numerous studies to negatively affect small populations. The loss of genetic diversity or amount of available DNA increases the susceptibility of a population to extinction.  If there is no genetic variation in a species brought back from extinction, will it survive in the wild?

“There would be variation in some of the material that we’ve got,” Professor Archer says.

“I don’t think that is necessarily an obstacle in any case. We do have a presumption that everything has to be genetically variable if you’re going to put it back in the wild. But in fact, we know about a lot of animals out in the wild that have very little genetic variation.”

“Cheetahs, for example, are virtually clones of one another but they’re doing very well. Pandas, have next to zero genetic variation but the only reason that they’re in trouble is because people keep on clearing there habitat – not because of their genetic composition,” he argues.

Studies by Professor Frankham however have shown that ‘bottlenecked’ populations (populations that have a sudden restriction in size) have an elevated risk of extinction under changing environments.

“A small proportion of such populations do survive similar times to large populations,” he admitted, “but they are typically genetically compromised and they are usually at greater risk to new threats of a different kind.”

But Archer remains unconvinced.

“It has become a mantra that if you can’t get genetic variation your species is doomed. I think we can presume for the time being that as long as we have a viable individual that was fine in that population originally, it will be a good thing to start out with,” he says.

Even if we assume that genetic variation will not be a problem, what about the reason the animal became extinct in the first place? Won’t the gastric brooding frog just die off again?

“Successful reintroduction of previously extinct species into the wild depends upon the original causes of extinction having been removed, and the recovered species having sufficient genetic diversity to evolve to cope with changing environments,” Frankham says.

“The combination of these is extremely improbable.”

The cause of the gastric brooding frogs disappearance is still unknown. However many scientists believe the chytrid fungus may be responsible for the disappearance of many frog species in Australia, including the gastric brooding frog.

“Many species are beginning to show a resistance to the chytrid fungus,” Archer explains, stating that there is obviously a mutated gene responsible for resistance in some frogs.

“Whatever that gene is that is something quite frankly that you could borrow and splice into the gastric brooding frog before releasing it back into that environment,” he said.

However Professor Frankham believes that ‘de-extinction efforts’ are even less justified if the original causes of the extinction have not been removed.

“It leads the general community to think that extinct species can be recovered, and this is currently not possible and even if it is done in the future, it will be very expensive and probably lead to a genetically very fragile species.”

On the other hand, Professor Archer points out that people want to know that there is a possibility that things like this can happen. They now have early stage embryos, which was technically impossible until a little while ago. He thinks the focus needs to be on the increasing success in this field.

“It is not clear that there is anything going to stop us. We have revitalised the DNA – it is now back in the world when it wasn’t before.”

“It creates the impression that extinction may not be forever,” Professor Frankham says and feels it should be the lowest priority in all conservation activities.

“It is very expensive and should not take funds from ‘normal’ conservation activities, where resources are grossly inadequate for conserving living threatened species.”

The gastric brooding frog may not be back yet, but Mike Archer and the ‘Lazarus’ team are still striving to turn the impossible into reality. Humans are responsible for nearly all extinctions we have any information about. Only time will tell if we can undo the damage we have caused and whether we should.

Local Conservation Efforts – IN FOCUS: Mogo Zoo

An inside look into the local conservation efforts making a global impact.

Video reporter: Shannon Kelleher

Many thanks to Mogo Zoo.