https://csiropedia.csiro.au/myxomatosis-to-control-rabbits/

The rabbits were introduced, along with foxes, so that the English colonists could enjoy their traditional hunting.

Then the rabbits multiplied. They cause massive environment and farming damage.

Then the Gubmint decided to try and use poisons to kill/reduce the population of rabbits.
This has failed many times. It also resulted in the rabbits who didn't die, to be a potential health risk to humans if eaten.
Also, they killed pet rabbits, inadvertently, by not realising that a trial toxin made its way from an island and back onto the mainland.

Also, rabbits became such a risk to agriculture that the guvmint built a pretty useless "rabbit proof fence"

:)