Feral Cats and Foxes Have Caused Australia’s Wildlife Crisis
February 11, 2015
Australian scientists claim that feral cats (cats that have reverted from domesticated animals back to their original wild or untamed state) and foxes are the cause of an extinction crisis that is affecting the country’s native mammals, in a study published this week in Proceedings of the National Academy of Sciences. As many as 30 species of Australia’s native mammals have gone extinct since the first European colonists arrived in 1788. This represents about 10 percent of all mammal species found in Australia. Many more native species are threatened with extinction, as well.
Australia’s high rate of mammalian extinction has long puzzled scientists. Researchers know that habitat destruction by people is the main cause of most animal extinctions over the past few centuries. However, large portions of Australia have only sparse human populations compared to the rest of the world. Furthermore, in Australia, many of the endangered species are small, unlike in other regions of the world, where larger animals are at the highest risk of extinction.
The scientists examined over 200 years of records of Australian wildlife extinctions searching for common elements. They found that the decline of many Australian native species coincided with the introduction of domestic cats and foxes. Cats were kept on ships to control rats and were introduced to Australia when the first European sailors arrived. Many cats have since escaped and reverted to a feral state. Red foxes, which were later introduced for sport hunting, also adapted well to the new environment. Both predators specialize in hunting smaller prey, such as the endangered quoll and numbat.
Wildlife experts point out that solutions for this problem are difficult and expensive. Campaigns to eradicate feral cats and foxes can lead to other problems. For example, when cats and foxes are removed, the population of rabbits, another introduced species, increases dramatically. Fenced reserves can provide protection for endangered mammals. However, fences that exclude predators are very expensive to build and require constant monitoring and maintenance.
Other World Book articles:
- History of Attempts to Save Species (a Special report)
- Invasive species
- Science stalks the domestic cat (a Special report)