An analysis of introduced sambar deer faeces has revealed that the invasive species is feeding on rare native plants in Australia’s Alpine National Park.
The research is published in the CSIRO’s Wildlife Research.
A team, led by James Cook University PhD candidate Matthew J Quin, collected 90 sambar deer faecal pellets in a 3-month period. The timespan coincided with the flowering time for many plant species.
DNA sequencing determined the different plant species present in the faeces.
In the droppings, the researchers identified 369 unique species from 35 families of plant and 80 genera.
Among the plant species is the Silky Snow-daisy (Celmisia sericophylla), which is currently listed as critically endangered under the Victorian Flora and Fauna Guarantee Act 1988.
The deer were also found to have chowed down on Hawkweed (Pilosella spp.), a highly invasive, non-native plant which has established itself in parts of the Alpine ecosystems.
The Victorian Alps have seen a dramatic increase in sambar deer numbers.
Sambar (Cervus unicolor) are native to the Indian subcontinent, southern China and Southeast Asia. It has been listed as vulnerable on the IUCN Red List since 2008.
But its numbers are increasing in parts of Australia where it was introduced by Europeans in the 1860s, along with hog, fallow, chital, rusa and red deer. Sambar are among the largest deer in Australia, reaching up to 230 kg.
Victoria is home to more than a million feral deer. The animals are one of the state’s biggest pest problems. More than 99% of the sambar deer population is believed to be in the state’s east where the Alpine National Park is located.
While measures have been put in place by the government to control the population, sambar numbers continue to rise and they have spread into vulnerable and delicate ecosystems such as the Alps.
The authors of the new research note “significant concern surrounds the potential for the species to impact rare plant species and vegetation communities.”
“Our results emphasise the need for careful evaluation of sambar deer impacts within individual sites and at small spatial scales,” they write. “The detection of species of conservation significance in the diet indicates that the presence of sambar deer should be considered a significant risk to biodiversity in areas of high conservation value.”