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00:00Australia's Tasmanian devil, renowned for its dangerous demeanour and terrifying temper,
00:15this is the world's largest carnivorous marsupial.
00:30They're fearless fighters
00:37and frenetic feeders,
00:38spending their lives screeching through the wild woods of Australia's island state,
00:51Tasmania.
00:56It's just one corner of this colossal ancient continent.
01:09Home to some of the planet's most unusual and fascinating animals.
01:17This is the secret life of the Tasmanian devil.
01:39When the first European settlers arrived in Australia,
01:45they found themselves surrounded by animal life that was utterly unfamiliar to them.
01:54They came up with their own names for these alien creatures.
02:00The koala was dubbed the monkey bear.
02:09The spiky echidna became the porcupine anteater.
02:15And the oddball wombat, a marsupial, was called a badger, a beaver and even a pig.
02:25These exotic creatures both mystified and delighted the new Australians.
02:30But there was one in Tasmania that totally terrified them.
02:48The settlers found the spine-chilling shrieks and unearthly wails that echoed around the bush
02:54at night so disturbing, they thought the animal that made them must be a kind of demon.
03:18They called it Beelzebub's pup, Beelzebub being one of the names for the devil.
03:36They're the size of a small dog, but so fearsome was the reputation of these animals,
03:41the early European settlers believed that if they fell from their horses in its territory,
03:47Beelzebub's pups would rip them limb from limb.
04:07Today Beelzebub's pup is called the Tasmanian devil.
04:15And although it's never actually dismembered a human,
04:20it's still famous for its extraordinary screeches,
04:26yowls
04:31and ear-splitting cacophonies.
04:38As well as its ferocious disposition.
04:53Devil fossils date back 70,000 years, suggesting the species is a relative newcomer.
04:59This carnivorous marsupial is a pocket predator that carries its young in a pouch
05:06and is always itching for a fight.
05:30In the wild, they live solely on the island of Tasmania,
05:46off the southeast coast of the Australian mainland,
05:50full of their preferred habitat, open forests and woodlands.
06:00It's thought the devils once lived on the mainland, but died out there.
06:06Perhaps because of competition with the dingo,
06:10a wild dog that arrived in Australia thousands of years ago and became an apex predator.
06:18But the dingo only made it to the mainland, which had already separated from Tasmania,
06:24so the island offered a safe haven for the surviving devils.
06:29But now they're facing extinction.
06:35The species is suffering from facial tumour disease,
06:39a deadly affliction they pass to one another through biting.
06:46It's estimated that since 1996, the population of Tasmanian devils
06:52has reduced by more than 80% and they're now officially designated as endangered.
06:59It's nearing nightfall and young male Carlos is emerging from his den.
07:22As devil numbers are in such sharp decline,
07:25he's part of a monitored population that is regularly health checked by conservationists.
07:34He's got an excellent sense of smell
07:38and he picks up on a scent. He sets off from his den to find the source.
07:48At two years old, he's now an adult. Lifespan in the wild is only around five or six years.
08:01He weighs over 17 pounds and may reach 26 pounds.
08:07All that weight is packed into a stocky body between one and a half and two and a half feet
08:12long. He may be modest in size, but this is one of nature's most formidable predators.
08:22His sturdy physique is packed with muscle.
08:35His legs are short and strong, while his large head and neck
08:39support one of the most proportionately powerful bites in the animal kingdom.
08:46The equivalent of a dog four times his size or for his body mass,
08:52more powerful than the bite of a tiger.
08:57The short broad skull shape means the muscles in the jaw have increased leverage,
09:04easily capable of crushing the skulls of live prey.
09:09And slicing clean through bones, fur and sinew.
09:21Large parts of the devil's waking hours are taken up with trying to find food.
09:26Mainly nocturnal, but happy to move around in the day, the devil's robust frame means it's
09:31able to travel long distances at a stretch, up to 10 miles at a time,
09:37looking for live animals to hunt or carry in to scavenge.
09:42Although it doesn't defend the territory, it does have a home range that it regularly
09:47travels around.
09:48And it's a big animal, it has a very large body.
09:55The devil's long-legged frame means it's able to travel long distances at a stretch,
10:00up to 10 miles at a time, looking for live animals to hunt or carry in to scavenge.
10:11The size and shape of these ranges depends on how much food is in the area.
10:22Carlos is on his evening foraging expedition.
10:31And it isn't long before he runs into another devil.
10:41Devils spend a lot of time alone, but their home ranges often overlap.
10:46And when they do meet, there's almost always a fight.
10:55For the pugnacious, peppery devil, brawling comes as naturally as breathing.
11:04Females are just as feisty as their males.
11:08Females are just as feisty as the males, and equally likely to engage in a rage-fuelled fracas.
11:19For the males, it's all about dominance.
11:22Gaining ascendancy over their rivals will pay off once breeding season arrives in March,
11:27as females often favour dominant males.
11:31But these power plays to decide top devil take place all year,
11:36and they can be about almost anything.
11:54Arguments can happen over having the whole log to themselves.
12:07Or a blow-up could be over a tiny scrap of food.
12:16To a devil, it's all worth biting over.
12:21Which is why a disease passed through biting has been particularly devastating to them.
12:36At the moment, Carlos is the local top dog, the most dominant male.
13:06He has to be even more aggressive than everyone else to keep his title.
13:37And he has to maintain his position all year long.
13:55Carlos has a pretender to his throne.
14:04Two-year-old Mongo.
14:07Every chance he gets, he challenges Carlos.
14:18He's looking to eventually usurp Carlos and take over his position as dominant male,
14:24giving him better chances at mating time.
14:36But so far, the battle-scarred Carlos has always chased off his challenger.
15:07He takes a lot of damage, but his backside is armoured with very thick skin.
15:13As well as giving a competitive edge at mating time,
15:16being the dominant male also gives an advantage on a day-to-day basis.
15:21At dinner time, he gets the first chance to feed.
15:31Tasmanian devils will eat almost anything.
15:39Insects, rabbits, rodents.
15:42They'll even actively hunt large live prey.
15:54Active hunting usually takes place at night, when the devil's eyesight comes into its own.
16:00It can see best in black and white, and its vision is based on movement,
16:04enabling it to spot the tiniest twitch the prey makes.
16:12White markings scattered over its flanks, chest and legs
16:16may help break up its distinctive predator outline.
16:23Hunting alone, using a combination of ambush and pursuit,
16:27a devil can bring down animals almost twice its size, like wallabies and wombats.
16:38It's an efficient, deadly hunter, but its real forte is scavenging.
16:48Devils spend most of their time looking for carrion,
16:51the carcasses and remains of dead animals.
16:54It's not uncommon to encounter it in the bush.
17:01Although devils live mostly solitary lives,
17:04when they find a large meal like this, they're able to come together.
17:10Much like vultures and hyenas in Africa, by cleaning up carcasses,
17:14they keep the bush free from rotting meat that could spread disease.
17:19And they're a friend to the farmer, who would otherwise have to bury the bodies of dead livestock.
17:30This is one of the devil's most valuable roles in the ecosystem.
17:38Like many carnivores, they use the easiest and fastest route through the carcass.
17:49By ripping their way through the tail area and the stomach cavity first,
17:56they can access the rump muscles and intestines as quickly as possible,
18:02leaving the harder to eat parts, like the head, for the late comers.
18:07The devil's dentition is adapted for both capturing live prey and crunching carrion.
18:29Like dogs, they have a whopping 42 teeth, compared to a cat's 30.
18:38Long, sharp canines hold and pierce prey, and molars shear through fur, sinew, and skeleton.
18:48They can eat all but the very biggest bones in a carcass.
18:54Tasmanian devils have even been known to chew through heavy steel wire.
19:08There are some large biological differences between marsupials, like the Tasmanian devil,
19:13and placental mammals, like dingoes and bats.
19:20Marsupials have very short pregnancies, and give birth to tiny,
19:24unformed young, which then develop within a few years.
19:28Most other mammals develop inside the mother, within a placental sac.
19:33Marsupials also have a metabolic rate around 30% lower than placental mammals.
19:40This means they can live using much less energy,
19:43a distinct advantage for when times get tough.
19:48The male marsupial is the largest of all mammals,
19:51but in times of plenty, the high-octane lifestyle of the devil
19:56means it typically uses more energy than its vegetarian cousins.
20:00So it aims to consume about 15% of its body weight every day.
20:09For these committed carnivores, the male marsupial is the most active.
20:14Their sense of smell is so acute that they can detect food from around half a mile away.
20:22They stand on the edge of a tree, where they can smell food from a distance.
20:29The male marsupial is the largest of all mammals,
20:32and has a metabolic rate around 30% lower than placental mammals.
20:36The male marsupial is so acute that they can detect food from around half a mile away.
20:44They stand on their hind legs to give them the extra height they need
20:47to pick up on a scent carried on the wind.
20:52When on the hunt for large prey like wallabies or wombats,
20:56the devil uses a mixture of stalking and short sprints.
21:00It relies on stamina rather than outright speed,
21:04but can still manage around 15 to 20 miles an hour for a few hundred yards.
21:10But if they're lucky, it'll be an easy meal, an animal carcass.
21:59The devils have struck gold. It's the remains of a wallaby.
22:14At first glance, it looks as though the devils are displaying their usual
22:18sky-high aggression levels over the carcass.
22:21But although it seems like a free-for-all, in fact, there's some devil etiquette at work here.
22:29The attitude is still present, but the bloodshed is absent.
22:39When feeding at a large carcass like this, the Tasmanian devil has evolved to be communal,
22:44which is extremely unusual for a male marsupial.
22:50But it's also unusual for a carnivore that spends most of its time being solitary.
22:58Everyone, even lower-ranking individuals, will get to feed,
23:02even if it takes them a while to pluck up the courage.
23:10Communal feeding means all the local devils get a good meal at least once in a while,
23:16and that's evolutionarily advantageous for the whole species.
23:21But it means they have to make the switch from all-out war to having some table manners.
23:31At a big feed, they avoid direct conflict by using ritualized posturings.
23:39Although they snap and scream at each other constantly, their teeth rarely actually connect.
23:45Their profuse whiskers extend to just beyond the width of their shoulders,
23:50so they can use them as sensors to judge the distance between them and another devil.
23:58They may jaw-wrestle where they stand up and place their paws on each other's shoulders or chests,
24:05and shake their heads constantly while vocalizing.
24:21This behavior is about each devil defending the amount of food that he needs,
24:26not the whole carcass. This is how they can all feed together.
24:34The size of the carcass affects the extent to which the feeding devil will chase off a challenger.
24:39And as this carcass gets smaller, dominant male Carlos decides his neighbor needs to back off.
24:52But even this exchange is without injury to either side.
25:09Ah!
25:22Whilst battle may be temporarily suspended, the noise level is still high.
25:31And this has its own important function. It alerts other devils in the area to the carcass.
25:40So they can come and join in the communal feed, saving them the energy of looking for other food.
25:49Tasmanian devils have many excellent adaptations to Australia's often harsh environment.
25:58A vital one is that they can consume a massive 40% of their body weight in a single sitting.
26:04They then store this extra fat in their tails, giving them a superb advantage in times of famine,
26:10which can occur in the dry forests and coastal woodlands they prefer to live in.
26:34Unlike some of Australia's other marsupials, devils can also very effectively control their body temperature.
26:59This thermoregulation means they can be active in the often blazing hot daytime without overheating,
27:08which vastly increases their scavenging and hunting opportunities.
27:17Another adaptation is that they can get most of their water requirements from their food.
27:25This can help them in case of drought.
27:29A lower ranking male picks up a scent.
28:00His eyesight is the weakest of his senses in the daytime,
28:04but it's good enough in combination with his sense of smell for him to find food when it's light.
28:15It's a lizard, a prime candidate for lunch, if he can track it down.
28:25The lizard takes cover under a rock.
28:30But the devil has another handy adaptation, wide feet with claws ideal for digging.
28:51Something scares him away.
28:54But he soon comes back.
29:11And this time, nothing will stand in the way of him getting his meal.
29:23The next animal to wander into devil territory is much more prickly.
29:37It's an echidna, an animal only found in Australia and neighbouring New Guinea.
29:45And it's utterly bizarre.
29:47It's from an early branch of mammals that still lays eggs like a reptile.
29:53And the males have a four-headed penis.
29:56Like the equally rare platypus, it's categorised as a monotreme,
30:01an animal that just has a single opening for excretion and reproduction.
30:06When threatened, it curls up and relies on its spikes to deter the aggressor.
30:12The spikes are actually modified hairs, and they're a sharp and effective deterrent
30:17against even the super teeth of the devil.
30:22The echidna can move them individually or in small groups.
30:26This means it can use them to right itself if it gets up anywhere.
30:31Even though the strange newcomer appears to be impenetrable,
30:35its discoverer wants to keep it to himself.
30:50The echidna is a very large animal.
30:52It's about the size of a hand.
31:24But eventually, they both have to give it up as a mission impossible.
31:54Meanwhile, Mungo, trying to climb the ladder of dominance and usurp Carlos,
32:00comes across a lower-ranking male who's found a piece of meat.
32:14But before Mungo can get involved, top devil Carlos turns up.
32:24Now, third devil joins in.
32:54Finally, Mungo gets in on the action.
33:11He grabs a big hunk of meat and makes his escape.
33:20The rules of tolerance that come into play at a big carcass
33:23so everyone can get to feed simply don't apply when the find is small like here.
33:34It's every devil for himself.
33:43Carlos makes off with a large piece of the meat
33:46and the other two fight over the scraps.
34:00Mungo did well out of the fight.
34:16Since they're mostly solitary, it's the presence of food that usually leads to many forms of devil communication.
34:26Vocalizations are the most obvious.
34:46There are at least 11 different kinds of vocalization.
34:54One of the most common is the arf sound, which shows curiosity.
35:00Other low-level sounds are the bark and snort and teeth chattering,
35:06which means the devil is uncomfortable.
35:16As the situation escalates, growling begins.
35:24Then full-scale screeching.
35:34This is when it's most likely to descend into a brawl or a chase.
35:46One of its most frequent communications is yawning.
35:52Its jaws can open to an astonishing 75 to 80 degrees wide.
35:58Humans can only manage around 33 degrees.
36:04A wide gape like this is common in carnivorous marsupials.
36:10The tiger quoll, a dedicated meat eater, also opens its mouth extremely wide,
36:16even as a baby.
36:22Yawning is a displacement activity that says,
36:28I've got a fine set of teeth here, but at the moment I'm not interested in a fight.
36:34It also helps relieve built-up pressure in their oversized jaws.
36:48Devils can also communicate via a range of chemical signals, especially in their poop.
36:54A diet that's so varied and largely indiscriminate
37:00results in disproportionately large faeces.
37:06An average scat is around 6 inches long, but they can be 10 inches.
37:12And it can be full of surprises.
37:16Items that researchers have found within devil scats include a woolen sock,
37:22aluminium foil, the head of a snake and half a pencil.
37:28After a while, the poop turns white, very like a hyena's faeces.
37:34This is due to the high levels of bone in both of their scats.
37:40Like many carnivores, their poop is pungent and full of information for other devils.
37:46All the devils in an area like to poop commonly in the same spot, known as a devil latrine.
37:52This serves as a kind of community notice board, letting local devils know who visited and when,
37:58possibly giving information about their age and breeding condition.
38:04Mungo does some marking, known as anogenital dragging.
38:10It may look like a male marking his territory, but females also do this,
38:16and devils aren't really territorial.
38:21The exact purpose of dragging is unknown, but it may be associated with the transmission of chemical signals,
38:27a form of communication.
38:51Tail positions, erect fur and head elevations are other non-vocal means of communication.
39:11In devil society, the female of the species is not the gentler sex,
39:17so two young females are arguing over a scrap of meat.
39:23It's not very big, but to a devil it's still worth fighting over.
39:39The girl's stiff legs and high head positions, as well as gaping jaws,
39:45can be a back off.
39:55But if all communication fails, for a devil, a fight is the preferred method of sorting an issue out.
40:01Although he has to be subordinate to top dog Carlos,
40:07Mungo is able to dominate many of the other local devils.
40:23Mungo's at the bottom of the bank,
40:29warning the other devil not to come any closer.
40:39His vocalizations intensify.
40:51A win for Mungo, he's chased off the interloper.
40:59With this level of daily aggression,
41:05it's unsurprising that the devils can sustain damage.
41:11Injuries are everywhere.
41:17Battered faces, tattered ears,
41:23and scarred backsides.
41:27This low-ranking male has lost the whole of his upper lip
41:33and part of his nose.
41:39He tries to avoid other males and get some rest during the daytime.
41:45But Mungo is on the prowl.
41:52He's a much higher ranking, more aggressive devil.
41:58The disfigured devil has to give way.
42:04But Mungo hasn't finished making his point.
42:10He follows and pins down the other male, forcing him into a confrontation.
42:22Which leaves the disfigured male cowering.
42:42After a hard day or night of inflicting or receiving grievous bodily harm,
42:48the devil typically retires to its den.
42:54It may regularly use three or four dens,
43:00and once established, it tends to use the same ones for life.
43:06In the mating season, it may share its home,
43:12These tend to be within banks,
43:18in dense vegetation near water, or even in a small natural cave.
43:24Sometimes it will take the time to dig out its own den in a preferred location.
43:30Or it may use a discarded wombat burrow.
43:36Wombats are fellow marsupials, although unlike the devil, they're vegetarian.
43:42They like similar habitat, and being slightly larger than the devil,
43:48their burrows are roomy and make for a spacious devil apartment.
43:58Mungo leaves his den to start exploring his patch for food.
44:06The disfigured male has blundered into the area, right on top of Mungo's den.
44:12If the more dominant devil notices him, he'll be attacked.
44:18But his outstanding sense of smell alerts him to the danger just in time,
44:24before Mungo's able to get into attack position.
44:30This time, he gets away safely.
44:44Out looking for food, Mungo runs into Carlos.
44:52It's a good opportunity to test the waters once more, and see who's top dog.
45:00Carlos once again emerges triumphant,
45:06retaining the rights to first claim of a carcass,
45:12and preferential treatment from the females come breeding season.
45:22Carlos retires to his den for some peace and quiet.
45:28Although being a devil, he's not quiet for long.
45:48Tasmania is a paradise for animal life,
45:54but the devils don't get everything their way.
46:00The devil's love of carrion is often their downfall.
46:06As they try to feed on an easy source of carrion, roadkill,
46:12they frequently become it themselves.
46:19It's important to try and boost devil numbers,
46:23through a conservation approach known as rewilding.
46:27This involves releasing health-checked devils
46:31from captive populations into the Tasmanian wilderness.
46:35These astonishing carnivores have short but action-packed lives.
46:41With their monumental anger management issues,
46:45and their zero-tolerance attitude, for a devil every day is an adventure.
46:51Despite treating their fellow devils with extreme prejudice most of the time,
46:57they're able to share a meal for the benefit of all.
47:01Full of character, their deafening volume,
47:07their tenacity,
47:11and their ability to clean the land
47:15make them one of Tasmania's most fascinating and useful creatures.
47:41Music
47:45Music
47:49Music