Tasmanian Devils Are Picky Eaters With Individualistic Food Preferences

Unlike other scavengers, they're able to mostly dine on whatever they like.

Tasmanian Devil
BerndC / Getty Images

By definition, scavengers will eat anything and everything that is available. That’s true for animals as diverse as hyenas, vultures, and raccoons who will dine on whatever they find.

But a new study finds that the Tasmanian devil is more of a picky eater. Researchers say they’ve developed their own preferences for what they’ll eat and have broken the laws of scavenging.

Earlier research on Tasmanian devils focused mainly on what they eat as a species, rather than as individuals, says Anna Lewis, Ph.D. candidate at the University of New South Wales Sydney, who led the study.

“This meant devils were always described as opportunistic feeders based on a long list of foods that a handful of individuals may have only eaten once or twice. When you only look at the big picture you can also risk oversimplifying how animals of various sexes, ages, and sizes might be feeding differently from one another,” Lewis tells Treehugger.

“As the devil is an endangered species, with wild communities suffering from a deadly transmissible cancer (devil facial tumor disease), it’s important that we replicate diets in captive populations with as much nuance as possible so that they have a better chance of surviving once healthy animals can be reintroduced into the wild.”

Not long ago, Lewis and her colleagues developed a model for measuring whisker growth patterns in Tasmanian devils. They knew they could track their eating habits with greater accuracy by analyzing small whisker samples from the animals.

“We were keen to use this new model to figure out whether all devils really fed on a wide range of items all the time or whether individuals show certain food preferences,” Lewis says.

Whisker Analysis

For their study, researchers analyzed whiskers from 71 Tasmanian devils captured in seven locations across Tasmania. They investigated their eating habits by looking at the chemical imprints from food located in their whiskers.

They found that only one out of 10 had a general diet where they appeared to eat just about anything that was available. The majority appeared to prefer certain foods, such as wallabies or possums. And favorites varied among devils.

The results were published in the journal Ecology and Evolution.

Researchers believe that Tasmanian devils can be finicky because they have very little competition from other species for carcasses.

“Instead, their main source of competition comes from each other. This means that there is likely a surplus of high-quality carcasses and devils can afford to be choosy, particularly in regions where devil facial tumor disease has dramatically reduced their numbers,” Lewis says.

“For now it’s hard to say whether devils are making conscious choices about what foods they eat. But there is some evidence that points towards this being the case as we found that larger devils, the ones better able to defend their dinner from intruders, are the ones most likely to be specialists. The only true generalist feeders were small devils in highly competitive populations, i.e. the ones most likely to lose in a fight.”

Fierce, Favorite Animals

Tasmanian devils have a reputation for being very fierce, disagreeable animals, Lewis points out.

“You only have to look up ‘Tasmanian devil scream’ online to see how they got their common English name,” she says. “Luckily most wild devils aren’t looking to pick a fight with the researchers that handle them and their instinctive fear response is to freeze. This makes snipping off their whiskers all the more easier, so long as you keep a good grip on their famously strong jaws.”

Each animal is microchipped before it is released, so researchers learn the personalities of the ones they see most often.

“Favourite devils include Arcturus, who returns to be trapped without fail every time we revisit his home range; Frangipani, who against the odds has survived to the ripe old age of five in a DFTD-affected population, probably by rejecting the advances of disease-ridden male suitors; and Pavlova, who in her old age set up residence in one trap for an unprecedented seven nights in a row,” Lewis says.

“Devils are also fascinating because of their status not only as the largest (and one of few remaining) marsupial carnivore species, but as perhaps the mammal best adapted for scavenging.”

They aren’t often discussed with other scavengers, she says, because they’re so far away at the bottom of the world.

“But they’re out there scavenging about 95% of their food and have all sorts of cool adaptations designed for finding and feeding on carcasses from their sensitive noses to their bone-crunching jaws to their energy-efficient mode of running,” Lewis says. “We’d love to see devils get more attention around the world for their impressive scavenging skills.”

Interestingly, researchers think that other scavengers might also be pickier if they didn’t have much competition for food.

“Particularly obligate scavengers, who only scavenge and never hunt, would probably have a higher capacity to specialize on certain desirable food items if they didn’t have to worry about the scarcity of carcasses in their environment,” Lewis says.

“Of course there are many other factors that go into determining how many carcasses are around—including the impact of human activities like driving and hunting—and these are components of the Tasmanian ecosystem that could influence devil diets we are keen to explore next.”

View Article Sources
  1. Lewis, Anna C. et al. "Effects of intraspecific competition and body mass on diet specialization in a mammalian scavenger." Ecology and Evolution, 2022. doi:10.1002/ece3.8338

  2. Anna Lewis, Ph.D. candidate at the University of New South Wales Sydney, who led the study

  3. Attard, Marie R. G. et al. "Whisker growth in Tasmanian devils and applications for stable isotope studies." Ecology and Evolution, 2021. doi:10.1002/ecs2.3846