Tasmanian Devil: Ghosts of Tasmania

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Speaker 1: Hi, I'm Rich Schwartz. Hi, I'm Abony Mone. Welcome to Amazing Wildlife, where we explore unique stories of wildlife from around the world and uncovered fascinating animal facts. This podcast is a production of I Heart Radio and San Diego Zoo Wildlife Alliance, in international nonprofit conservation organization behind the San Diego Zoo and Safari Park. This next species is a carnivorous marsupio. At one point in time, this animal was only found in one place in the world. Have you guessed it, Well, here's an even better clue. This animal was the main character in his own popular cartoon. But despite this spotlight, there's a lot you might not know about the Tasmanian Devil. Rick. Let's unpack a few of those facts. The Tasmanian devil was once only found in one place in the world. Rick, Where can you find the Tasmanian devil living in nature today? Well, it's true, ebany Tasmanian devils were once found throughout Australia, but keep in mind that was a long long time ago and throughout the last several centuries they have only been on the island state of Tasmania. And although their range encompasses the entire island of Tasmania. They tend to be pretty partial to the coastal scrub land and forest areas. But get this. Recently a small breeding population of Tasmanian devils were reintroduced in New South Wales, Australia on the mainland. So this reintroduction is the first of three planned reintroductions of small breeding populations of Tasmanian devils. This of course was done with a lot of preparation and planning to ensure the best possible outcome for these new mainland populations. The Tasmanian devil, as I mentioned, is a carnivorous marsupial. So we've been talking enough and we've done enough of these episodes. I have learned that that means it eats me, and it carries it's young it's offspring in a pouch. Correct correct, yes, So let's start with its diet. What does the Tasmanian devil eat? Let's prey to the Tasmanian devil. Well, first of all, hats off to you have any I appreciate that you have been learning along with our audience as well, because that means we're doing a good job here. But but you're correct, tasmine and devils are carnivores, and that means, like you said, they only eat meat. Now, their usual prey consists of birds, reptiles, amphibians, and you know, sometimes other small mammals. Sometimes maybe they can catch a small kangaroo or small wallaby. Now that said, they are also part of nature's cleanup crew. This is probably the most important part of what they do. This means, like vultures, they will happily consume carry on or an animal that has already passed away. No hunting required for them this way. And get this that tasmine and devil's jaws are so powerful they can easily crush and ingest the bones of any animal that they are consuming. Thus you will rarely find anything left mind after the Tasmanian devils are done with a meal. Wow, now I thought this is pretty cool. Rick. Can you describe how one can tell if a Tasmanian devil is well fed? Yeah? Well, Tasmanian devils are well known for having a voracious appetite. They seem to be born with the idea that every meal is a competition that must be one at all costs. In fact, They can even consume get this of their body weight in one meal, I mean almost half their body weight and one meal. But how can you tell if one's been eating well over the last few meals. Well, you might be thinking you're looking for a big belly, but like other mammals, they store extra calories as fat. But unique to marsupials, they store this fat in their tail, So a plump tail means they've been eating. Well, wow, that's so interesting. So the Tasmanian devil has a fierce reputation um possibly because of its name. What's the story behind its name? I know what you mean, but I mean the named devil is right there. It's like that doesn't really give you a very warm, fuzzy feeling, does it at all? When European settlers first came across these carnivorous marsupials, it was, how can I put this? Not a pleasant encounter. In general, Tasmanian devils don't attack people, but they put on quite an aggressive looking and loud show if they feel threatened, making all sorts of growls and screams that are really quite impressive for a smaller animal like they are. With this, they will also gave their mouth open incredibly wide, showing all these very sharp teeth. Oh and their ears become flush with blood, making them turn bright red in these situations, adding to the whole dramatic look and behavior of everything. And of course settlers brought with them that you know, their livestock is specifically chickens and other small animals that ended up being very easy prey for the Tasmanian devils. So the Tasmanian devils took advantage of these easy meals, making nightly raids into the chicken yards. And here's the thing. When Tasmanian devils end up feeding to together, they make a horrendously large amount of noise is they fight over the food. All of this has earned them the initial nickname of the devil, and eventually the name then became Tasmanian Devil. I can see why they got that name exactly. It all really kind of makes sense when you see the history of it. And I want our listeners to keep in mind. They really aren't an animal you would consider big. I mean, they only weigh around eighteen to twenty five pounds and at the most two feet in length. So what a Tasmanian devil lacks in size, they make up in complete and total attitude. Well, that explains it. So other popular marsupials, like the kangaroo are often pictured carrying their offspring and a pouch, and those cute pictures that circulate. But I was surprised to learn that the Tasmanian devil also tote they're young. Can you tell us about the reproductive cycle of the Tasmanian Devil? Oh? Absolutely, But first, Ebony, I want to catch any new listeners up to speed on what it means to be a marsupial, And basically that means you were born very small and underdeveloped, with eyes and ears not formed yet no hair. Usually only the forelimbs are developed with functional digits. Then that little underdeveloped baby called a joey must climb from the birth canal to mom's pouch to find the milk duck to latch onto for the next several months. And you might have heard that term joey with kangaroos or kowala's, but the term joey sticks for all marsupials, including the Tasmanian Devil. Now, in the case of the Tasmanian Devil, they are about the size of a grain of rice when they are born weighing less than the half of one gram. And remember earlier when I mentioned that they seem to have this very competitive behavior around feeding, Well, it does in fact start on day one, and it's a matter of true survival. You see, the mom can give birth to up to fifty babies at one time, but she only has for milk ducks. And when a marsupial Joey latches on, due to the physiology and body mechanics, they will stay connected to that milk duck for several months, meaning the first four to reach and stay attached to one of the four milk ducks lives and the arrest will perish. Wow, it's like survival of the fittest, no fastest, most aggressive. I don't know. Wow, So what is the relation between mom and Joey? Like, how long does the offspring stay with mom? Yeah? With the Tasmanian devils, the joys will usually stay in mom's pouch for about three to four months, and then they stay in the den for about another three months as Mom comes and goes with food to feed them. At about six months of age, they start to venture out of the den. Following mom or writing on her back learning how to be an adult Tasmanian devil. Then when they get around nine to ten months of age, the young will start to head off on their own. That brings us to social dynamics. Do the Tasmanian Devils like? Do they interact with each other in ways not related to reproduction? Well, I guess you could say for the most part meany, the Tasmanian devils are considered solitary, but with a network built in at What that means is they don't live in family groups or travel and packs. There's no real hierarchy dynamics to everything they do, but they do come together often when feeding and of course for mating and when mom is raising her joeys. This means that they do have interactions with a network of other Tasmanian devils that live within the same regions. And it is worth sharing that during group feedings we do see the larger, usually older and stronger individuals dominating the smaller, younger ones, but this is truly based on a physical contest of pushing and biting each other. No real social dynamic as far as that kind of structure. So what role does the Tasmanian devil play in its habitat oh i, meaning they are very important to their ecosystem. As we mentioned that, they do prey upon a variety of smaller animals and this of course helps keep those populations in check and balanced. But equally important, if not even more so, it is the consumption of carry on are already deceased animals that we talked about earlier. Any animal that is part of nature cleanup crew, consuming dead and decaying things helps prevent the spread of disease and helps move along the process of the life cycle. And it's worth noting ebony. With the recent reintroduction of the species back on mainland Australia, biologists and ecologists are both expecting to see a rebalancing of the forest ecology, much of which has been out of balance in the past due to introduce cats, foxes and other invasive species. Rick, you mentioned reintroduction. The Tasmanian devil population is endangered unfortunately, and some scientists predict extinction could be inevitable. What's the Tasmanian devils like major threat to survival? Well, unfortunately, for decades, this sort of really kind of horrible facial cancer has been decimating the Tasmanian devil population, spreading from animal to animal. When these stocky raccoon sized marsupials bite each other, and it's worth noting they don't just randomly bite each other. Part of these sort of group feedings we were talking about, where the dominant ones pushed back the less dominant ones. You know, this is done through biting, just sort of a normal way that they communicate with each other. And it is said when this face cancer didn't exist yet, that sure it would leave scars, but it wouldn't really damage them too much. Unfortunately, now this transmits this cancer and it kills up to the devils in Tasmania. They're only a home. For quite a long time, some researchers saw extinction as inevitable as you said, eany until recently. In fact, the cancer was spreading exponentially like a pandemic across the population of Tasmanian devils. But geneticists have calculated that each infected devil now transmits the tumor self to just one or fewer other devils, and that could mean the disease may disappear over time. There's also an interesting fact that they have found some populations that were free of this disease, and they were able to isolate them and send them away from the island to help prevent them from catching this disease. So they have created some safe populations and they're also monitoring this very closely. In coming up, we'll talk more about how teams at the San Diego Zoo Wildlife Alliance are working with partners to address other Tasmanian devil conservation efforts. The first this now it's time for the San Diego Zoo Minute, an opportunity for you to learn what's new at the zoo and Safari Park. The San Diego Zoo has one of the largest colonies of Gallas tortoises in the world. We have had these giants in our care since, making them the oldest residents at the Zoo. That's the year when Charles Townsend of the New York Zoological Society began his efforts to save the tortoise from extinction by collecting juvenile tortoises and setting up colonies for them in North American zoos. Did you know Tasmanian devils sneeze to help avoid a fight. It's true. These are known as bluff behaviors or behaviors that are an attempt to scare an opponent before a real scuffle starts. Oh, and get this, Tasmanian devil's travel a long distance each and every night in their pursuit of food, sometimes covering as much as ten miles. We're continuing our conversation about the Tasmanian devil and the cancer that threatens to wipe it out. Joining the conversation now is Corrus Singleton, a senior veterinarian with San Diego Zoo Wildlife Alliance High Cora hi Aberty. In scientific terms, what is the devil facial tumor disease? Devil facial tumor disease is a transmissible or contagious cancer, and that's very different than the cancers that we typically think of, which develop within an individual and stay within that one individual. Devil facial tumor can be transmitted from one devil to another, just like an infection. And you've probably never heard of a contagious cancer because they're very rare, and there are only three that are known to infect mammals in the entire world. Of those three Tasmanian devils, of two of them, So how are Tasmanian devils transmitting this cancer and what's happening to them once that happens. Facial tumors are spread mostly by biting, which is a common behavior among Tasmanian devils. As their meeting and as they're feeding, devils bite each other on the head in the neck, so the tumors are observed to grow mostly around the mouth. And these tumors can grow very large and make it very difficult for the devils to feed, so many of them die from starvation. So what a researchers know about the history of this disease. Is it known how or or where it originated. Yes, researchers do know how and where the devil facial tumor disease originated. This disease was first documented in in northeastern Tasmania actually by a wildlife photographer, and this disease is spread rapidly south and west across the island and over the past twenty five years, population numbers have declined by almost across the island of Tasmanian. The second Tasmanian devil facial tumor disease was diagnosed in so there are two different transmissible tumors that devils have, and can this transmissible tumor? Can it be transferred to other animals? Can another animal be infected by this disease? No, devil facial tumor can only affect Tasmanian devils. Other animals, including people, have an immune system that's able to recognize tumor cells as invaders and kill those tumor cells. So if we were to contact a tumor from a Tasmanian devil, our body would recognize that that was abnormal and would not allow it to grow. But the reason that this tumor can infect so many devils is that the devil immune system is unable to recognize those tumor cells as foreign invaders, so the devil's body allows the tumors to grow. Is this tumor a threat to the population at the st Ago Zoo. That's a great question, Ebony, because it's a really scary disease and we're lucky that the answer to that is no. Because facial tumor disease is a cancer of wild devils only, and as this disease in the wild caused populations to get smaller, conservationists agree that it would be really important to protect populations of devils that are free from the disease. So some wild devils were brought into human care, and part of that process involved really long observation periods where they were able to monitor devils for several years to make sure that they didn't have the facial tumor disease before they entered these protected populations. So the three Tasmanian devils who live at San Diego Zoo were born within these protected populations and are free from this horrible disease. So what is the case of the Tasmanian devil and the Tasmanian devil facial tumor disease? What does that say about the importance of genetic diversity when it comes to conservation. By studying genetics of Tasmanian devil, researchers hope to better understand how this disease and the devil are evolving together so that we can focus our conservation work to help the devil survive this threat. In speaking of conservation work, what has the San Diego Zoo Wildlife Alliance done to address this problem? At the San Diego Zoo Wildlife Alliance, we focus our conservation efforts in eight hubs around the world, one of which is the Australian forests, where we work to conserve the Tasmanian devil as well as koalas and platypus, and we're partnering with governmental conservation and research groups to learn more about why the devil has this cancer as well as how we can help conserve the devil populations in the wild. And specifically we've partnered with the Save the Tasmanian Devil Foundation and the Australasian Wildlife Genomics Group at the University of Sydney to learn more about the genetics of the devil. During these conversations, we've talked about human behavior being the driver of extinction for some animals, but in this case, the Tasmanian devil populations have been devastated by cancer. Someone my question, if human intervention is therefore the appropriate response, given that this is a non human cause problem, what would you say to that, Yes, definitely, of any that can be a difficult question to tackle, but really there aren't really any ecosystems around the world that are untouched by human behaviors via either climate change or pressures of development, or introduced species such as foxes and feral cats in Tasmania. So while the facial tumor disease is not a problem caused by humans, we have altered the ecosystem and the climate in ways that make it more difficult for the devil to adapt to this disease, and human behavior directly contributed to the extinction of another apex predator on Tasmania, the Tasmanian tiger, leaving the devil to fill this important ecosystem role. So humans depend on healthy ecosystems and our behaviors threatened this delicate balance. So I see it as our responsibility as environmental stewards to help the devil fight this disease. From a veterinarian's perspective, does anything about that has Menian devil in particular stand out? Does it require any sort of special care? Tasmanian devils are really interesting. First off, they're very charismatic animals and it's really enjoyable to work with them. But interestingly, from a biology standpoint, they have a really short lifespan for a mammal, and in the wild they only live up to about five years, and in human care that can live to be seven or eight years of age. And while devils and zoos do not have devil facial tumor disease, they do develop cancers, many different types of cancers, at a higher rate than many other animals. So since we know this about devils, we've designed a healthcare program specifically for the Tasmanian devil that helps us to detect and to treat cancers early. And it's really rewarding to see the work that we do help an animal live a longer and healthier life. What would you say is the best part of your role as a senior veterinarian with a San Diego Zoo Wildife Alliance, I feel fortunate to be part of a conservation organization with a one health approach where I can channel my passion for animals and my skills in support of conservation. And one health refers to the interdependence of wildlife health, ecosystem health, and human health, And for me, each day at work is interesting and full of variety. In the morning, I might be called upon to help an injured insect or an ill elephant, and then in the afternoon I'll work with a global team of conservation allies to help devils or koalas or platypus in Australia, and I know that what I do here at San Diego's a Wildlife Alliance helps the animals living in our care as well as helps the animals in their habitats worldwide. What would you say to a kid who wanted to one day be a veterinarian? Any advice? M Yeah, lots of advice. So why do most kids say that they want to be a veterinarian Because they love animals. They love animals and they want to help animals. That's right, and veterinarians do help animals in many different ways, sometimes by doing exams and giving treatments and performing surgery, but also sometimes by studying animals in their habitats or by doing health research in a lab. And at its core, being a veterinarian is about science and service service to both animals and people. So hard skills like science and math are just as important as soft skills like communication and teamwork. And while I think that being a clinical veterinarian is fantastic, kids should know that there are many different ways that they can help animals and many different ways that they can help and work with animals. My best advice is to be curious and explore all the different ways that they could work with animals, find out where their passion for animals overlaps with the things they're really good at and the things that they really like to do. So maybe you're passionate about wildlife and you like to work with computers, Or maybe you're passionate about wildlife and you like to take pictures and make video those or write stories, or maybe you like to design things. Are you like to organize and lead teams? All of these people work at San Diego's a Wildlife Alliance helping animals, And for me, my passion is wildlife and conservation. I'm good at biology, learning how systems work and solving problems, and I like to work directly with individual animals and populations of animals. So being a wildlife veterinarian is perfect for me. And I think if kids can explore and be curious, they can find those places where their passions, their skills, and their interests overlap in support of animals. Great advice. We've been talking to Cora Singleton, a senior veterinarian with the San Diego Zoo Wildlife Alliance. Thanks Cora, thank you. Thanks for listening. We hope you enjoyed learning about the largest marsupio carnivore in the world, the Tasmanian Devil, and being sure to subscribe and tune into next week's episode, in which will be jumping into the story of one of the more recognizable marsupials from Australia. I'm Ebony Money and I'm Rick Schwartz. Thanks for listening. If you would like to find out more about San Diego Zoo Wild Lack Alliance, please visit sdz w a dot org. Amazing Wildlife is a production of I Heart Radio. Our producer is Nikkia Swinton and our executive producer is Marcia to Peanut. Our audio engineer and editor is Sierra Spreen. For more shows from My Heart Radio, check out the I Heart Radio app, Apple podcast, or wherever you listen to your favorite shows.