A James Cook University researcher has been poring through deer poo using new DNA analysis tools - looking to discover more about the habits of an invasive deer damaging agricultural landscapes.
JCU PhD candidate Matthew Quin lead a study trying to better understand the diet of chital deer, four of which were introduced to northern Australia in 1886 and whose population had grown to around 44,000 by 2014.
He said invasions by non-native species are a leading cause of species extinctions and a major contributor to ecosystem change.
"Invasive, plant-eating ungulates (hoofed mammals) can reduce vegetation biomass and alter nutrient cycles, which can negatively impact other native herbivores and ecosystems.
"Chital population size and distribution are expanding, so effective methods to understand and restrict further range expansion is a high priority," said Mr Quin.
The team examined the diet of 149 culled chital over a two-year period, using DNA metabarcoding of faecal samples.
"Recent advances in DNA analysis have enabled rapid, efficient and accurate identification of samples.
"We can detect significantly more dietary items consumed by individual chital deer and find unique things not found using older methods," said Mr Quin.
He said the metabarcoding technique showed that the diet of chital deer in the tropical savanna landscapes of northern Australia is dominated by tree foliage and shrubs throughout the year.
"This is in contrast to previous studies which suggested chital mostly eat grasses and grass-like plants during the wet season," said Mr Quin.
He said in Australia, competition with livestock is considered a major agricultural impact of introduced deer.
"Our findings suggest this may be less of a concern in our study area, as the DNA analysis suggests that chital are primarily feeding on trees and shrubs, which might reduce competition with cattle for pasture," said Mr Quin.
