While exploring the Australian wilderness, it is advised to be on the lookout for animals exhibiting interesting behavior. A recent discovery made by our research team highlights the unpredictable nature of wildlife encounters.
In 2023, Elliot Bowerman, a colleague from Sunshine Coast Council, embarked on a two-night trip to New England National Park. This park is known for its towering mountain peaks, reaching an impressive 1,500 meters along Australia’s mid-east coast.
During his trek to Point Lookout on the afternoon of August 17th, Elliot stumbled upon a fascinating sight. While examining some plants along the trail, he heard a rustling sound coming from the bushes ahead. Upon closer inspection, he witnessed a small mammal dragging the carcass of another mammal and devouring it.
At first glance, this behavior may not seem unusual, as mammals often consume each other. However, it is rare to observe small mammals in such close proximity during daylight hours. Recognizing the significance of this sighting, Elliot captured the scene on video using his mobile phone.
It was only after several days of reviewing the footage that our research team realized they had captured something rarely seen in the wild. This remarkable event has now been published in the journal Australian Mammalogy.
The creature captured on film was an antechinus, a native marsupial commonly found in forested areas across eastern, south-western, and northern Australia. Antechinuses typically feed on insects, spiders, and occasionally small vertebrates such as birds, lizards, or even other mammals.
However, the video footage clearly showed a mainland dusky antechinus (Antechinus mimetes mimetes) consuming a dead member of its own species. This behavior is highly unusual and sheds light on the complex nature of these marsupials.
Antechinuses are known for their “suicidal reproduction,” a phenomenon called semelparity. This means that after a single breeding period, they die. While semelparity is observed in various plants, invertebrates, and vertebrates, it is rare among mammals.
During the breeding season, male antechinuses experience a surge in hormones, including cortisol and testosterone. The combination of these hormones leads to organ failure and the eventual death of all males. However, before their demise, they mate with multiple females for extended periods, ensuring the survival of the species.
Returning to the incident at Point Lookout, it is believed that the antechinus turned to cannibalism due to the breeding period’s intense calorie burn and limited food availability during the cold winter months. The living males and females took advantage of the fallen comrade as a source of cheap energy.
In some areas of Australia, multiple antechinus species coexist, with their breeding periods often overlapping. It is plausible that individuals may not only consume members of their own species but also feed on other species.
Each species may benefit from consuming dead males of the other species. For the earlier-breeding species, females may be pregnant or lactating, requiring significant energy. On the other hand, the later-breeding species needs to gain weight and improve body condition before their own breeding period begins.
This discovery sheds light on the orgiastic breeding and opportunistic cannibalistic feeding habits of antechinuses. It serves as a reminder to keep a keen eye and ear open while exploring the Australian bush, as nature has many secrets waiting to be revealed.
The author would like to acknowledge Elliot Bowerman from Sunshine Coast Council and Ian Gynther from the Queensland Department of Environment, Science, and Innovation as co-authors of the published paper.