In the remote Cambodian jungles, we made sure rare Siamese crocodiles would have enough food



The Siamese Crocodile once lived in Southeast Asian freshwater rivers, but now fewer than 1000 individuals exist.
Shutterstock

Paul McInerney, La Trobe University

For nine hours, my colleague Michael Shackleton and I held onto our scooters for dear life while being slapped in the face by spiked jungle plants in the mountains of Cambodia. We only disembarked either to help push a scooter up a slippery jungle path or to stop it from sliding down one.

With our gear loaded up on nine scooters – 200 metres of fishing nets, two inflatable kayaks, food for five days, hammocks, preservation gear for collection of DNA, and other assorted scientific instruments – we at last arrived at one of the few remaining sites known to harbour the critically endangered Siamese crocodiles.




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If a croc bite doesn’t get you, infection will


The Siamese crocodile once lived in Southeast Asian freshwater rivers from Indonesia to Myanmar. But now, fewer than 1000 breeding individuals remain.

In fact, during the 1990s the species was thought to be completely extinct in the wild. Then, in 2000, scientists from Fauna and Flora International found a tiny population in the remote Cardamom Mountains region of Cambodia.

We travelled to this remote wilderness in 2017 to determine habitat suitability for the reintroduction of captive-bred juvenile Siamese crocodiles. We wanted to understand the food web there to see whether it contains enough fish to sustain the young crocs.

Our journey would not have been possible without the help of Community Crocodile Wardens – local community members who patrol the jungle sanctuaries for threats and record crocodile presence. Wardens also conduct crocodile surveys further afield to discover new populations or to identify new areas of potential suitable crocodile habitat for juvenile releases.

Our recent study found to ensure the species survives, reintroduction locations must be protected from fishing pressure – both from a food supply perspective, but also from risk of entanglement in nets.

A species in decline

When we arrived at our site, northwest of the village of Thmor Bang, our day was capped by what we came to know as the standard evening downpour, despite assurances that we had, in fact, timed our trip for the dry season.

Kayaks were inflated, nets set, and sampling was underway. This proved laborious – to ensure crocodiles didn’t drown, we couldn’t leave nets unattended in the water overnight, but instead checked them every hour until morning.

Siamese crocodiles are generally not aggressive to humans, but they come into conflict with people when caught in fishing nets.

This often leads to the crocodile drowning and the fishing net being ruined. It’s a disaster on both counts, because fish is the only source of protein for many local communities in Cambodia.

Like many other apex predators around the world, the Siamese crocodile is also in decline because of habitat destruction and poaching for their skins.

Their potential large size and generally placid nature means they are highly prized by crocodile farmers who use the skins for handbags and footwear. Crocodile farmers also often hybridise the Siamese crocodiles with other non-native crocodile species.




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This means programs for Siamese crocodile reintroduction and breeding must carefully genetically screen all young crocodiles bred in captivity to make sure they’re not actually hybrids, so the “genetically pure” wild populations can remain.

Finding fish bones in croc poo

Despite a pretty good understanding of captive Siamese crocodile behaviour and biology, very little is known about Siamese crocodiles in the wild, such as what they eat or how much food they need to raise an egg to adulthood.

Our only reliable indication of diet comes from scats (crocodile poo or “shit of croc” as we came to call it) collected along the river banks inhabited by remnant populations.

Carefully collected poo samples containing scales and bones tell us fish and snakes make up a significant proportion of the Siamese crocodile diet.

But the shrouded, mystical, extremely remote and virtually inaccessible jungle in the Cardamom Mountains has ensured we know next to nothing about fish communities within habitats set for the release of captive crocodile. And this information is particularly important for prioritising release locations for captive bred juveniles.




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We spent four days sampling fish communities and then repeated the process at two other equally remote locations within the Cardamoms, requiring two days travel between each.

We saw groups of gibbons moving through the forest and macaques climbing down from trees to drink at the river. But at last we spotted a wild Siamese crocodile after dark, swimming in our morning bathing pool, on our second-last day.

Ultimately, we distinguished 13 species of fish from the Cardamom Mountains, confirming the presence of two previously unconfirmed species groups for the region.

What’s more, we found fish density was highest in areas with more Siamese crocodiles, and lowest in areas with more human fishing pressure.




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Staying safe in crocodile country: culling isn’t the answer


Understanding the food web of crocodile reintroduction sites is important, because conservation managers need to understand the ecological carrying capacity of the system – the number of individual crocodiles that can be supported in a given habitat. Learning this is especially important when historical information does not exist.

Preservation of fish stocks within Siamese crocodile habitats is critical for survival of the species. But a key challenge for natural resource managers of the Cardamom Mountains is balancing crocodile density with local fishing necessity, and to do this, we need more information on Siamese crocodile biology.The Conversation

Paul McInerney, Research Fellow, La Trobe University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Banning exotic leather in fashion hurts snakes and crocodiles in the long run


File 20190326 139349 ur5jll.jpg?ixlib=rb 1.1
Yellow anaconda (snake) skins pegged to dry by indigenous people in Argentina.
Tomas Waller, Author provided

Daniel Natusch, Macquarie University; Grahame Webb, Charles Darwin University, and Rick Shine, University of Sydney

We are all familiar with the concept of “fake news”: stories that are factually incorrect, but succeed because their message fits well with the recipient’s prior beliefs.

We and our colleagues in conservation science warn that a form of this misinformation – so-called “feelgood conservation” – is threatening approaches for wild animal management that have been developed by decades of research.

The issue came to a head in February when major UK-based retailer Selfridges announced it would no longer sell “exotic” skins – those of reptile species such as crocodiles, lizards and snakes – in order to protect wild populations from over-exploitation.

But this decision is not supported by evidence.




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Too simplistic

Banning the use of animal skins in the fashion industry sounds straightforward and may seem commendable – wild reptiles will be left in peace, instead of being killed for the luxury leather trade.

But decades of research show that by walking away from the commercial trade in reptile skins, Selfridges may well achieve the opposite to what it intends. Curtailing commercial trade will be a disaster for some wild populations of reptiles.

How can that be true? Surely commercial harvesting is a threat to the tropical reptiles that are collected and killed for their skins?

Actually, no. You have to look past the fate of the individual animal and consider the future of the species. Commercial harvesting gives local people – often very poor people – a direct financial incentive to conserve reptile populations and the habitats upon which they depend.

If lizards, snakes and (especially) crocodiles aren’t worth money to you, why would you want to keep them around, or to protect the forests and swamps that house them?

Women raise Burmese pythons at a small farm on Hainan Island, China.
Daniel Natusch, Author provided



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Biggest man-eaters in the billabong

The iconic case study that supports this principle involves saltwater crocodiles in tropical Australia – the biggest, meanest man-eaters in the billabong.

Overharvested to the point of near-extinction, the giant reptiles were finally protected in the Northern Territory in 1971. The populations started to recover, but by 1979-80, when attacks on people started to occur again, the public and politicians wanted the crocodiles culled again. It’s difficult to blame them for that. Who wants a hungry croc in the pond where your children would like to swim?

Saltwater crocs are the reason many beaches are not open for swimming in northern Australia.
Shutterstock

But fast-forward to now and that situation has changed completely. Saltwater crocs are back to their original abundance. Their populations bounced back. These massive reptiles are now in every river and creek – even around the city of Darwin, capital of the Northern Territory.

This spectacular conservation success story was achieved not by protecting crocs, but by making crocs a financial asset to local people.

Eggs are collected from the wild every year, landowners get paid for them, and the resulting hatchlings go to crocodile farms where they are raised, then killed to provide luxury leather items, meat and other products. Landowners have a financial interest in conserving crocodiles and their habitats because they profit from it.

Saltwater crocodile eggs collected in the Northern Territory, Australia.
Daniel Natusch, Author provided

The key to the success was buy-in by the community. There are undeniable negatives in having large crocodiles as neighbours – but if those crocs can contribute to the family budget, you may want to keep them around. In Australia, it has worked.

The trade in giant pythons in Indonesia, Australia’s northern neighbour, has been examined in the same way, and the conclusion is the same. The harvest is sustainable because it provides cash to local people, in a society where cash is difficult to come by.




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Decisions without evidence

A collector captures a yellow anaconda in Argentina.
Emilio White, Author provided

So the evidence says commercial exploitation can conserve populations, not annihilate them.

Why then do companies make decisions that could imperil wild animals? Probably because they don’t know any better.

Media campaigns by animal-rights activists aim to convince kind-hearted urbanites that the best way to conserve animals is to stop people from harming them. This might work for some animals, but it fails miserably for wild reptiles.

We argue that if we want to keep wild populations of giant snakes and crocodiles around for our grandchildren to see (hopefully, at a safe distance), we need to abandon simplistic “feelgood conservation” and look towards evidence-based scientific management.

We need to move beyond “let’s not harm that beautiful animal” and get serious about looking at the hard evidence. And when it comes to giant reptiles, the answer is clear.

The ban announced by Selfridges is a disastrous move that could imperil some of the world’s most spectacular wild animals and alienate the people living with them.The Conversation

Daniel Natusch, Honorary Research Fellow, Macquarie University; Grahame Webb, Adjunct Professor, Environment & Livelihoods, Charles Darwin University, and Rick Shine, Professor in Evolutionary Biology, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

If a croc bite doesn’t get you, infection will



Image 20170419 32700 mceytd
Open wide … the mouths of crocodiles like this contain bacteria that cause potentially lethal infections in people they bite.
from www.shutterstock.com

Simon Smith, James Cook University

Most people assume if you’re unlucky enough to be bitten by a crocodile, then a severed limb or other severe trauma is all you have to worry about. But new research is emerging about serious infections you can catch from a bite that might kill you instead. The Conversation

Our study, published earlier this week, showed the range of bacteria crocodiles can transfer to their human victims. The good news is they can be cured with a much simpler antibiotic treatment than we realised.

Since crocodiles were granted protected species status in the 1970s in Australia, they have attacked more than 100 humans.

For those lucky to survive, their injuries often become infected. Bacteria can enter the body via the deep cuts from a crocodile’s teeth or from wounds occurring when people try to escape.

Bacteria living in crocodiles’ mouths can come from the intestines of other animals they eat or from the water in which they live.

When people are trying to escape a crocodile attack, bacteria living in the soil and mud also pose a risk. And bacteria commonly living on our skin without causing problems can cause infection when the skin’s protective barrier is lost.

If untreated, bacteria can cause severe wound infections. Without treating these infections properly, the victim’s tissues die and their arms and legs may need to be amputated. Infection can also enter the bloodstream and spread to the rest of the body causing multiple organ failure and death.

How do we treat croc bite infections?

Australian guidelines recommend how to treat infections after bites from animals in general. But until recently we didn’t know much about which antibiotic is best for people who have been attacked by a crocodile.

Crocodiles make the front page across Australia’s Top End.
NT News

Some 25 years ago, a study in the Northern Territory found over half of people who had been attacked by a crocodile had infected wounds.

Researchers found a wide variety of bacteria you would expect to find in the water, the soil, the intestines of animals and on the skin of humans. To kill all of these potential infection causing bacteria, they recommended a complex treatment of four different antibiotics which would mean up to 14 injections a day. With so many antibiotics, this increases the risk of potential side effects and the cost of patient care.

So, we reviewed all cases of people who had been treated for a crocodile attack in Far North Queensland and attended the Cairns Hospital over a 25-year period.

A total of 15 people needed medical attention after a crocodile attack over this time, including several crocodile handlers. Four people were clearly infected by the time they reached hospital. A further two had bacteria in their wounds and almost all needed surgery.

Surgery is essential to prevent new or worsening infection after any bite as surgeons can remove already-infected tissue and help flush out any bacteria hiding in the wounds.

Despite finding lots of different bacteria, we discovered antibiotics given orally (amoxycillin-clavulanate) in mild infections or intravenously (piperacillin-tazobactam) for severe infections would be suitable to kill almost all of the bacteria found after a crocodile attack.

Although all of these patients were treated at Cairns Hospital, the results of the study will likely influence national guidelines for the management of crocodile attacks. The results may even help doctors in other countries.

Prevention is your best bet

Although we did not find it in our study, another important thing to remember is tetanus – an infection that can be contracted through dirty wounds – may also develop after a crocodile attack and this can be prevented by vaccination.

When it comes to crocodile attacks, like most things in health, prevention is better than cure. People should take care when visiting areas where crocodiles live. If people are attacked and lucky enough to survive, they are likely to require surgery and have a high chance of developing an infection.

A crocodile is a beautiful creature to observe from a distance, but in the words of American composer Frank Churchill:

Don’t be taken in by his welcome grin.

Simon Smith, Adjunct Lecturer (Clinical), Medicine, James Cook University

This article was originally published on The Conversation. Read the original article.

Croc safari: why selling licences to rich hunters isn’t fair


Claire Brennan, James Cook University

Crocodiles are protected in Australia. These impressive, if dangerous, animals are icons of the north. But it wasn’t always so. Crocodiles used to be hunted freely in northern Australia, an activity that led to their decline and eventual protection.

There have been calls to cull crocodiles to improve safety, but experts argue that this will make little difference to the risk. Besides, crocodiles are already sustainably farmed for leather products.

However, there are also calls – for instance, from federal MP Bob Katter – to allow crocodiles to be shot for safari. Selling hunting licences worth thousands of dollars to rich shooters, the argument goes, could provide vital income.

But this ignores Australia’s history of crocodile hunting.

Crocodile hunters in the Northern Territory.
Australian News and Information Bureau, July 1968/National Archives of Australia, CC BY

Postwar crocodile hunting

Immediately after the second world war, .303 rifles were widely available and were capable of reliably killing crocodiles. Crocodile skins suddenly increased in value — the Australian crocodile-hunting boom was the result.

The boom attracted hunters from southern Australia, including new immigrants. Some made significant amounts of money as the price of crocodile skins rose, but the prospect of adventure was often a far more significant lure. For many, coming north to hunt crocodiles was a working holiday combined with a boy’s own adventure. It was also an opportunity for men restless from the war to put off settling back into domesticity.


Australian News and Information Bureau, July 1968/National Archives of Australia, CC BY

That mood of adventure was captured in a 1956 home movie, aptly titled Northern Safari. Shown as a feature film, it packed cinemas in Australia and overseas. Northern Safari documented a family trip north and showed the accessibility of hunting in northern Australia to anyone with the time and practical skills to get there.

In addition to this accessible but rugged style of hunting, some postwar entrepreneurs began to offer organised hunting. Aimed at people with more money, less time and a greater desire for comfort, the commercial Australian safari was born.

The Australian Crocodile Shooters’ Club actively promoted safari cruises to hunters who wished to shoot in luxury. In 1952 it established one of Australia’s first safari camps in the Gulf of Carpentaria.

However, the Australian safari at this time was less exclusive than the original African version. While expensive, hunters might subsidise their holidays through the sale of crocodile skins – and the services and amenities provided could not be described as truly luxurious.

Safari hunting in the present

Nevertheless, the Australian safari has evolved since the ban on crocodile hunting and has taken its place among international safari organisations. Safari operations cater to visiting sportsmen by providing access to introduced species and game fish. The Australian experience is one of many such distinct experiences promoted at the annual Safari Club International convention.

An NT croc hunter in 1949.
National Archives of Australia, CC BY

New Zealand provides an example of how such tourist trophy hunting operates. Based on privately owned red deer estates, some hunting providers sell clients the right to hunt an animal selected for its probable value under the Safari Club International scoring system.

Estate deer are bred for their trophy value and their antlers command scores unmatched by red deer found on public land. Access to them is limited and the cost of hunting one of the highest-scoring stags is more than NZ$20,000. Estate deer hunting is largely invisible to ordinary New Zealand hunters.

Despite the enthusiasm of proponents, there is widespread unease about the killing of big game. As with the red deer industry in New Zealand, the safari industry in Australia at present depends on introduced species of game, and so avoids controversy.

Overseas the death of Cecil the lion brought public unease about big game hunting into the open, as did the participation of touring New Zealand rugby players in a legal hunt in South Africa. Privileged access to native game and the killing of large native animals for sport has been made more visible by the sharing of images via the internet, and that visibility has demonstrated widespread public unease with the safari.

So who gets to hunt?

Scientific commentators agree that crocodile culling is unlikely to decrease the number or severity of crocodile attacks on humans in Australia. Neither is hunting crocodiles in Australia about managing an introduced pest.

A croc hunter stuffing crocodiles for sale in 1949.
National Archives of Australia, CC BY

Instead, it is desirable because of the adventure involved, because for some hunting provides a meaningful connection with nature and because for others killing large animals brings prestige. These motivations aren’t being discussed.

If the crocodile safari were to be re-established in Australia it wouldn’t be the freely available experience it once was. Modern safari hunting is expensive and the preserve of only a few. Australians need to consider if they really wish to entice elite international hunters to Australia using a native species (even one as unlovable as the saltwater crocodile) as prey.

The Conversation

Claire Brennan, Lecturer in History, James Cook University

This article was originally published on The Conversation. Read the original article.

Staying safe in crocodile country: culling isn’t the answer


Adam Britton, Charles Darwin University

The killing of tourist Cindy Waldron by a saltwater crocodile while swimming north of Cairns on Sunday has reignited the debate about how to keep people safe from crocs. Federal MP Bob Katter has called for a bigger crocodile cull, although the Queensland government has once again ruled this out. There are very good reasons for this decision.

The evidence suggests that calls for complete deregulation of croc hunting are based on flawed arguments. The easiest way to keep people safe is to make sure they understand the risks.

What have we been doing about crocodiles?

Crocodile populations have been managed in northern Australia since the early 1970s. Before that, it was open season: three decades of hunting wiped out 95% of wild crocodiles, although getting them all proved impossible.

Many hunters grew to respect these unequivocally Australian “beasts”, supporting their subsequent protection. Yet their numbers bounced back much faster than anyone expected. Questions were soon being asked about the wisdom of allowing their recovery.

Sub-adult saltwater crocodile basking on a tidal mud bank, a popular sight for the many tourists who visit northern Australia each year.
Adam Britton

Recognising the value of crocodiles to people and ecosystem health, the Northern Territory government changed tack. Crocs became tourism icons, their eggs and skins were harvested sustainably to create local jobs and a fledgling industry, and safety issues were managed by the targeted removal of “problem” crocodiles, alongside visible media campaigns about staying safe. Despite differences between states and territory, the same basic approach is still used.

Has it been effective in saving lives? The first subsequent recorded fatal attack in Queensland happened in 1975, when Peter Reimers was killed while wading in a creek near Mission River. This was only a year after the crocodile population had been protected because it was on the verge of disappearing. Three decades of unregulated hunting hadn’t saved Reimers’ life.

The latest statistics as compiled by CrocBITE show 112 attacks between 1971 and May 2016, 33 (30%) of them fatal. That’s an average of 2.5 non-fatal attacks per year and 0.7 fatal attacks per year across Western Australia, the Northern Territory and Queensland. The rate has increased slightly over the past decade, but crocodile attacks remain extremely rare in Australia.

Number of reported saltwater crocodile attacks per country (April 2007 to April 2014). Fatal proportion in red, percentage shows fatality rate.
Adam Britton / CrocBITE

The average size of crocodiles is increasing as the population continues to mature towards full recovery. However, given the very low number of attacks, it’s difficult to assess if this has had any impact on the fatality rate.

Attacks usually happen because people get in the water with crocodiles. Such an obvious cause should be easy to prevent, and indeed this is the case.

Attack risk in Australia is low, largely because of the success of long-running campaigns to warn people of the dangers of swimming in crocodile-populated waters.

What lurks beneath? If you’re in crocodile habitat and you find water, always assume that it harbours a crocodile.
Adam Britton

Those who live locally are generally most keenly aware of the dangers. Sadly, a disproportionate number of attack victims are visitors who aren’t as aware of the risks. The real problem can therefore be interpreted as a failure to communicate risk, and therein lies the solution.

How to not get eaten by a crocodile

Crocodile attacks are traumatic, unfortunate and potentially tragic incidents that generally can be avoided. Australia has an excellent track record in saving people from crocodile attack. Despite having more saltwater crocodiles than any other country, we have low fatality rates because our management and education program is world-class.

Other countries with crocodiles come to Australia for advice on how to manage their crocodile populations and prevent conflict with people.

But there’s still a grey area for many people. How do you know whether it’s safe to swim in northern Australia? What’s the risk of doing so?

We make decisions every day to assess risk, whether we’re driving, walking down the street, swimming in a pool, or taking a boat out on the water. We’ve been trained to minimise the risks we face.

The same is true of going into the bush and facing potential dangers from snakes, mosquitoes or other animals. Sometimes accidents will happen, often because someone decided to push their luck.

Distribution of saltwater crocodiles throughout their range, including northern Australia. Green are viable populations, orange are recently extirpated populations and blue represents their potential for movement within and between countries.
Brandon Sideleau / CrocBITE

But with crocodiles the rules are simple: don’t enter the water in crocodile habitat. In these areas, stay away from the water’s edge, don’t disturb water consistently in the same place, don’t approach or tease crocodiles, camp at least 50 metres from the bank, and don’t go out in small, unstable boats.

Warning signs about crocodiles are there for a reason, to allow you to make an informed decision about your personal safety. Ignore them and you may get away with it, but eventually you will not.

The name ‘saltwater crocodile’ is misleading. They are equally at home in freshwater habitats.
Adam Britton

There’s little doubt that Australia knows how to manage wild crocodile populations. The risk of being attacked by a crocodile here is vanishingly small because crocs and people are managed effectively.

We already have a limited cull of crocodiles; the targeting and removal of specific animals that, through their actions, pose an elevated risk to the public. A wider cull won’t gain anything, at the cost of local livelihoods and our natural resources.

This article was co-authored by Erin Britton, a biologist at Big Gecko Crocodilian Research in Darwin.

The Conversation

Adam Britton, Senior Research Associate, Charles Darwin University

This article was originally published on The Conversation. Read the original article.