Drones, detection dogs, poo spotting: what’s the best way to conduct Australia’s Great Koala Count



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Romane H. Cristescu, University of the Sunshine Coast; Celine Frere, University of the Sunshine Coast, and Desley Whisson, Deakin University

Federal environment minister Sussan Ley this week announced A$2 million for a national audit of Australia’s koalas, as part of an A$18 million package to protect the vulnerable species.

The funding might seem like a lot – and, truth be told, it is more than most threatened species receive. But the national distribution of koalas is vast, so the funding equates to about A$1.40 to survey a square kilometre. That means the way koalas are counted in the audit must be carefully considered.

Koalas are notoriously difficult to detect, and counts so far have been fairly unreliable. That can make it hard to get an accurate picture of how koalas are faring, and to know where intensive conservation effort is needed – especially after devastating events such as last summer’s bushfires.

Methods for counting koalas range from the traditional – people at ground level looking up into the trees – to the high-tech, such as heat-seeking drones. So let’s look at each method, and how we can best get a handle on Australia’s koala numbers.

Environment Minister Sussan Ley holding a koala
Environment Minister Sussan Ley has pledged $2 million for a national koala count.
Glenn Hunt/AAP

Why we need to know koala numbers

Gathering data about species distribution and population size is crucial, because governments use it to assess a species’ status and decide what protection it needs.

In announcing the funding, Ley said the new audit aims to fill data gaps, identify where koala habitat can be expanded, and establish an annual monitoring program.




Read more:
Koala-detecting dogs sniff out flaws in Australia’s threatened species protection


So far, population estimates for koalas at the state and national level are rare and highly uncertain. For example, the last national koala count in 2012 estimated 33,000-153,000 in Queensland, 14,000–73,000 in NSW and 96,000-378,000 in the southern states.

This uncertainty can make it hard to detect changes in population trends quickly enough to do something about the threat, such as by limiting development or logging. However, the new audit can use methods not available in 2012, which should help with accuracy.

Three koalas in trees
To date, estimates of koala numbers have been highly uncertain.
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So how do you actually count koalas?

Finding a koala can be difficult. There may be few individuals spread over large areas. And koalas are well camouflaged and quiet, unless bellowing. Finally, they can sit high in the tree canopy.

In numerous research and management programs, we have observed that even the most experienced koala spotter may only see 20–80% of koalas present at a site, especially if the vegetation is thick or the terrain difficult to move through.

Romane Cristescu with detection dog
Romane Cristescu with detection dog USC x IFAW detection dog Bear. Detection dogs have been trained to locate koala and their scats.
Detection Dogs for Conservation

Making the job even harder, existing koala habitat maps can be highly inaccurate and miss unexpected hotspots. However, computer modelling using the latest methods, if carefully validated on the ground, can produce more accurate maps.

Traditional surveys involve multiple people independently searching the same area, and correcting counts based on the number of koalas each observer sees. This helps account for the difficulties in koala counting, but it’s hard, slow and costly work.

Searching for koala scat (poo) also is a common method of determining koala habitat – wherever koalas spend time, they will leave scats. However, the small brown pellets are easily missed, and large surveys for scats are time consuming.

Detection dogs have been trained to locate koala scats: in one study, dogs were shown to be 150% more accurate and 20 times quicker than humans.

And because male koalas bellow during the breeding season, koalas can also be detected with acoustic surveys. Audio recorders are left at a survey sites and the recordings scanned for bellows to determine whether koalas are present.

Recently, heat-seeking drones have also been used to detect koalas. This method can be accurate and effective, especially in difficult terrain. We used them extensively to find surviving koalas after the 2019-20 bushfires.

Citizen scientists can also collect important data about koalas. Smartphone apps allow the community to report sightings around Australia, helping to build a picture of where koalas have been seen. However, these sightings are often limited to areas commonly traversed by people, such as in suburbia, near walking tracks and on private property.

Adult and juvenile koala
Everyday citizens can help with koala counting.
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Getting the koala count right

All these methods involve a complex mix of strengths and weaknesses, which means the audit will need input from koala ecologists if it’s to be successful. Survey methods and sites must be chosen strategically to maximise the benefits of the funding.

Robust research data exists, but is patchy across the koala’s entire range. The first step could include collating all current data, including community sightings, to determine where additional surveys are needed. This will allow for funding to be prioritised to fill data gaps.

It is promising that the announcement includes monitoring over the long term. This will help identify population trends and better understand the response of koalas to ongoing threats. It will also reveal whether actions to address koala threats are working.

Finally, while threats to koalas are generally well understood, they can vary between populations. So the audit should allow for “threat mapping” – identifying threats and looking for ways to mitigate them.

Saving an iconic species

Last summer’s bushfires highlighted how koalas, and other native species, are vulnerable to climate change. And the clearing of koala habitat continues, at times illegally.

Government inquiries and reviews have shown state and federal environment laws are not preventing the decline of koalas and other wildlife. The federal laws are still under review.

However, the new funding underpins an important step – accurate mapping of koalas and their habitat for protection and restoration. This is a crucial task in protecting the future of this iconic Australian species.

Koala sleeping in a tree
The koala count is critical to protecting the species.
Shutterstock



Read more:
Stopping koala extinction is agonisingly simple. But here’s why I’m not optimistic


The Conversation


Romane H. Cristescu, Posdoc in Ecology, University of the Sunshine Coast; Celine Frere, Senior lecturer, University of the Sunshine Coast, and Desley Whisson, Senior Lecturer in Wildlife and Conservation Biology, School of Life and Environmental Sciences, Deakin University

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

What can you learn from studying an animal’s scat?



A bear leaving its calling card.
Dean Harvey/Flickr, CC BY

Verity Mathis, University of Florida

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com.


What can you learn from studying an animal’s scat? – Cora, age 9, Brookline, Massachusetts


Everybody poops. There are even whole books written about it. And we can learn a lot about animals from what they leave behind.

Scientists study animal poop, also called scat, to learn about the hidden lives of animals. We can find scat in the wild and know what type of animal left it based on its shape, size and contents.

I study mammals, so I know that a pile of brown pellet-shaped scat that’s about the size of chocolate-covered raisins could be a sign that there are white-tailed deer in the area. Bigger, tube-shaped scat with hair and bones in it might be from a coyote.

The Smithsonian National Zoo uses scat to assess lions’ health.

Scat can tell us a lot about an animal’s diet, habits and movement, so scientists like to study it both in nature and in the lab. Outdoors, scat can identify what animals are present in an area. Then researchers take it to a lab, dry it out and dissect it for clues about the animal’s diet.

Some mammal poop is full of seeds, which shows that the animal eats fruit or berries. Or it might contain bones and fur, which scientists can identify to learn what species that animal is eating.

Animal scat also contains DNA – molecules inside the cells of organisms that carry genetic information. Extracting DNA from scat is a non-invasive way to study animals, since scientists don’t need to handle the animals to learn about them.

DNA from scat can tell scientists about the genetic health of a species, who is occupying what territory, and the relationships of groups of animals in a particular area. For example, DNA from the scat of rare Bengal tigers in India helped scientists estimate how many tigers were in an area, see where individual animals were traveling and better understand their genetic relationships.

Studying animal scat can also support conservation. Some researchers have trained dogs to sniff out the scat of endangered species, such as the blunt-nosed leopard lizard, which is found only in a few grasslands in central California. By locating an endangered animal’s scat, scientists can estimate how many of that species are left in an area, analyze its diet and do DNA testing without having to disturb it.

It’s not hard to find scat if you know where to look. Some mammals, such as coyotes and bobcats, like to poop in the middle of trails or trail crossings. Others, like porcupines, do their business at the bases of trees. Guidebooks and websites can tell you what kinds of scat you’re likely to find in your area.

It is important never to pick up scat with bare hands, since you don’t know what kind of diseases might be present. But you can use a stick to look at it and see if you can figure out what the animal was eating, or take pictures and look in a guide to identify the creature that left it behind.


Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to CuriousKidsUS@theconversation.com. Please tell us your name, age and the city where you live.

And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.The Conversation

Verity Mathis, Mammal Collections Manager, Florida Museum of Natural History, University of Florida

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