Feral Cats Push Critically Endangered Australian Marsupial to Brink of Extinction

The Kangaroo Island dunnart isn’t one of the most well-known marsupials (like koalas, opossums or kangaroos), but it’s one of the rarest. The cute, mouse-size animal lives on Kangaroo Island off the coast of South Australia. Experts estimate that only 500 of the little critters still exist, and that number is under threat from feral cats.

The IUCN Red List, a catalog of threatened species, lists the island dunnart as critically endangered, a status one step removed from being extinct in the wild. Massive bushfires spread across the island in 2019 and 2020 and burned 98% of the rare mammal’s habitat.  

A study published in the journal Scientific Reports on Thursday investigated the danger that cats pose to the small remaining population of Kangaroo Island dunnarts.  

The researchers examined the stomachs and digestive tracts of 86 feral cats collected from conservation areas on the island between February and August 2020. Seven of those cats had the remains of eight different Kangaroo Island dunnarts in their systems, pointing to what could be a much larger problem. “Our results confirm for the first time that feral cats do predate on KI dunnart and that they were efficient hunters of this species directly after the fire,” the research team reported.  

The study highlights the importance of controlling feral cats on the island. “The combined pressures of a small, isolated population, natural disasters like bushfires, and predation from introduced predators such as feral cats could lead to the extinction of this vulnerable species,” Scientific Reports publisher Springer said in a statement.

The team also found the remains of an endangered bandicoot, highlighting the pressures feral cats place on other threatened species.   

The Kangaroo Island feral cat eradication project is part of a government effort to reduce the impact of invasive cats on native wildlife. Cats are captured and euthanized. Said the KI Landscape Board in an explainer, “Should the eradication program succeed, Kangaroo Island will become the largest inhabited island to be free of feral cats — generating enormous benefits to the island’s ecosystems and economy.”