Australia is an island so many native species aren’t use to surviving with animals brought from the outside such as rabbits or cats. That’s why Australia has to resort to such ambitious projects creating rabbit and cat-proof fences.
The cat-proof fence is designed to keep cats out of a specific area so the native animals can safely live and breed. Without the cat-proof fence, cats would risk killing and eating the animals, wiping out entire species in the process.
If you thought your cat caused problems, imagine the problems Australia faces trying to keep their native species from getting killed by a cat.