Humans altering Tasmanian devil diets: study
Human environmental impacts, like land clearing, are narrowing the diet of the Tasmanian devil and potentially leading to increased chances of a deadly facial cancer spreading.
A study spearheaded by the University of NSW analysed chemical stamps in whisker samples of devils living in different environments to determine their diet.
Researchers found devils in human-impacted landscapes, such as cleared land and regenerated native forests, fed on the same food items, primarily medium-sized mammals.
In environments like rainforests, devils ate a broader range of prey and incorporated smaller animals, such as birds, into their diets.
"The more that habitat was impacted by humans, the more restrictive the diet became," lead author and PhD candidate, Anna Lewis, said.
"They may be turning to human-derived sources of food, such as highway roadkill, which are more readily available."
Devils with a narrower diet run the risk of interacting more frequently around carcasses.
Ms Lewis said this was of "particular concern" for the spread of the highly contagious Devil Facial Tumour Disease.
The disease, which was first detected in northeast Tasmania in the mid-1990s, wipes out about 80 per cent of the populations it infects.
It was recently detected in the state's northwest in one of the last remaining areas thought to be disease free.
"The highest rate of cancer transmission, other than during the mating season, occurs when they're feeding around these large carcasses," Ms Lewis said.
"There could be an increased chance for the disease to spread amongst devils, and the devils themselves are also at risk of being hit while feeding."
Researchers say their findings highlight an urgent need to protect remaining untouched landscapes, both for the devils and the species they eat.
"It's apparent there is much more diversity of species available in these old-growth forests," Professor Tracey Rogers, ecologist and senior author, said.
"The devils are shining a light on how vital these pristine areas are."
Devils living in regenerated native eucalypt forests also ate a smaller variety of food items.
Their diets were closer to devils in cleared agricultural land than those from undisturbed forest regions.
Scientists hope to better understand the grassland eating habits of the species, which is listed as endangered, in future research.
The study was published in the journal Scientific Reports.