Tasmanian Devil – It’s Habitat, Behavior and Predatory Activities
The Tasmanian Devil is the most important native predator in its habitat. Its famous gape, screech and snarl are dramatic bluff behaviors used during fights over dominance or food, especially when around carrion.
These marsupials are environmental vacuum cleaners, consuming meat, hair, bones and organs from carcasses. They are nocturnal and usually solitary but occasionally congregate around carcasses to feed.
Features
The Tasmanian Devil is a ferocious marsupial renowned for its blood-curdling screech, vicious feeding habits, and black fur that helps it blend in with the night’s dark landscape. Historically vilified and persecuted to near-extinction, attitudes towards these remarkable little critters have since done a U-turn – but they are still at risk from a mysterious cancer that is rapidly destroying the wild population.
About the size of a small dog, Tasmanian devils belong to the family Dasyuridae, which includes some 69 extant species. They share many morphological characteristics with long-extinct early marsupials, such as separate toes and simple pouches. They have a stout build and large head, and can emit a powerful, pungent smell when frightened. Like other members of their genus, devils are highly mobile and opportunistic predators that predominately feed on carrion, with the ability to take down animals larger than themselves. They also forage for wombats, kangaroos, wallabies, birds, fish, insects and fruit.
They have a distinct, long tail that they use to swivel to adjust their body position for balance and to catch flying insects. They are solitary animals, but during mating season, males will compete for females by using vocalizations, posturing and physical combat.
A common sight around Australia, Tasmanian devils are a keystone species, playing an important role in the ecosystem as scavengers and top predators. They are nocturnal and crepuscular (active at night and just before sundown), and feed on dead animal flesh. They are often sighted foraging on the beach for dead fish, or hunting water rats and sheep’s legs that have slipped out of shearing sheds.
The uniqueness of the Tasmanian devil lies in its 42 teeth that grow continuously throughout their life. Unlike other dogs, the tassie devil’s teeth can be used to break apart bones, which is a necessity when it comes to eating carcasses. Its teeth are also one of the reasons why tassie devils have such a distinctive, unpleasant smell – the same scent they give off when fighting or marking territory. They are also the only known mammals to have an olfactory gland that produces such a strong, unpleasant odor.
Behavior of the Tasmanian Devil
Despite their fearsome appearance, Tasmanian devils are not vicious. They typically spend their days in hollow logs, caves, or burrows, emerging at night to hunt and eat. Their powerful jaws are put to good use – they’ll eat anything they can sink their teeth into, including carrion.
These marsupials are opportunistic hunters and will prey on a variety of animals, from birds to mammals to reptiles. They will also eat insects, fungi, berries and roots. The diet of Tasmanian devils varies with season, location, and habitat conditions. On mainland Australia, the species is known to mainly eat small to medium-bodied mammals such as common ringtail possums (Pseudocheirus peregrinus), Bennett’s wallabies (Macropus rufogriseus) and Bennett’s kangaroos (Macropus tataricus). On Tasmania, the animal preys on a wider range of animals including reptiles, fungi, insects and berries.
Though they are generally solitary, Tasmanian devils congregate when feeding on carcasses and are known to engage in ferocious group feeding frenzy. They can gorge themselves, eating up to 40% of their body weight during a single meal session. During these meals, the devils interact with each other and may even fight. Agonistic interactions rarely result in physical clashes but many devils display scarring on the head and neck from this type of behaviour.
Devils communicate with visual (20 postures) and vocal (11 sound forms) signals, such as a loud gaping mouth, yawning, barking, fierce snarls and high-pitched screams. They can sneeze as well, but this is more a signal of stress and anxiety than aggression.
Females release a scent around their habitat when they are ready to mate, and males then follow it. They will then fight each other to mate with the female. The most dominant male typically wins. Males will have multiple mating partners throughout their lifetime.
Because of their social and opportunistic behaviors, these creatures are vulnerable to diseases such as the deadly Devil Facial Tumour Disease (DFTD). The DFTD outbreak has caused a precipitous decline in Tasmanian devil numbers, and the animal is now listed as Endangered. Thankfully, a variety of conservation programs are underway to help save these iconic Tasmanians and restore their populations.
Habitat
The late-night screeching, stress-induced smell and fierce looks of this marsupial gave it the name “devil.” Although they once lived throughout Australia, Tasmanian devils are now found only in the state of Tasmania. They are mainly scavengers but can also be effective predators. They have powerful jaws that can completely devour their food, including bones, fur and organs. They also bury leaf litter to help protect their young from wildfires. They are sometimes referred to as ecosystem engineers because their actions enrich soils, disperse seeds and lower the intensity of wildfires.
This small animal’s long whiskers and sensitive ears aid in navigation at night and in avoiding predation. Its powerful bite is one of the strongest for its size of any carnivorous mammal.
While many people think of Tasmanian devils as pests, they are an important part of the local ecosystem. They keep down populations of domestic dogs and foxes that threaten livestock, and their scavenging habits benefit farmers by keeping rodents away from crops. Their numbers increase dramatically each summer, when the young leave their mother’s pouch and begin scavenging on their own.
Although their preferred habitat is open forest, they can survive in a wide variety of landscapes, including shrubland and wetlands. They do not stray far from their dens, which are usually hollow logs or old wombat burrows. The entrance to a devil’s den is often visible in the grass, but cobwebs or vegetation across the opening may indicate that it is currently not being used.
Female devils are ready to breed when they reach sexual maturity in their second year. After a gestation period of 21 days, they will give birth to anywhere from two to four young, called “joeys.” Young devils are pouch-bound for about four months and then remain with their mothers until they are weaned.
A major threat to the population is Devil Facial Tumour Disease (DFTD), which is transmitted through biting and fighting. DFTD causes tumors that interfere with an animal’s ability to eat and eventually lead to starvation. Other threats include attacks from domestic dogs and foxes, getting hit by cars as they scavenge for roadkill at night, and loss of habitat. The good news is that a healthy devil population can be restored through efforts such as habitat protection, providing human-free areas for them to live and breed.
Feeding Habits of the Tasmanian Devil
While they are solitary by nature, devils often gather together to feed on carcasses—which is where most of the growling and screeching takes place! They are gorge feeders, meaning they eat large quantities of food at one time. They are also scavengers and will clean up any animal carcasses that have fallen. At the San Diego Zoo, for example, devils are known to eat thawed rabbits, mice, rats and fish, as well as cow bones to chew. As a result, they help to keep local wildlife populations healthy.
After a gestation period of 21 days, a female Tasmanian Devil will give birth to between 20 and 30 young, called joeys, which will remain in her rear-facing pouch for four months. The tiny joeys must race from the birth canal to their mother’s rear pouch to attach themselves to one of the four available teats, using their claws. Many joeys will die before they make it to the mother’s pouch. Those that do survive will grow to be strong enough to face the Tasmanian bush, but they will still need the mother’s milk for sustenance.
Laurel and her colleagues have found that the diets of devils vary with season and habitat. For example, devils living in regenerated native eucalypt forests that have not been disturbed for decades consume a greater variety of foods than those in cleared pastures. This suggests that preserving wild landscapes is crucial for the survival of devils, which need to be exposed to a wide range of genetically diverse prey to develop immunity against DFTD.
Another discovery made by Laurel is that devils are very good at climbing trees to escape predators, and will even climb into bird nests to steal eggs and grub. They are also capable of releasing an odor when they feel threatened, much like a skunk. This is a useful defensive tactic, since it will alert any other devils within close proximity that they need to stay away from the danger. However, as a devil grows in size it will lose its ability to climb trees, which is why young devils are so adept at using their tails to hold themselves up against branches and other surfaces.
