"Rabbits are declared animal pests in the Auckland Regional Pest Management Strategy. They destroy pasture and native plants as well as vegetation in neighbouring gardens."
It's all too common for people to abandon their unwanted pets outside, but Bassett said "one pair of rabbits can result in 100-plus rabbits" in a year if uncontrolled.
"Liberating pets into the wild is not in the pets' best interest and can often lead to animal welfare problems," Bassett said.
She is calling on owners of rabbits and other pets to take greater responsibility for their animals, and to rehome or dispose of them appropriately if they cannot care for them.
Auckland Councillor Cathy Casey has been photographing rabbits and other animals believed to have been dumped at the park.
Recently, one of her staff contacted the SPCA on her behalf regarding an abandoned Dutch rabbit there.
Last weekend, a Herald reader saw a woman releasing one brown-gray and a frosted pearl lop-eared rabbit at the park.
"At first we thought she was just letting the rabbits play in the grass, but then I saw her just walk off and drive away in her car," said the reader, who did not want to be named.
Casey said owners who abandon their pets in public parks are "mean and abusive" and were breaking the law.
"People who witness such acts should take a picture and report them," she said.
Dumping an animal in this manner is a prosecutable offence under the Animal Welfare Act 1999.
SPCA spokeswoman Jessie Gilchrist said the society was getting reports of dumped and abandoned animals "far too often".
She stressed that releasing domestic animals into the wild is not the solution when a pet is no longer wanted.
"A domestic rabbit released into the wild without care can suffer terribly," Gilchrist said.
"They could succumb to the elements, get sick from disease, subjected to acts of cruelty, get injured or be attacked by another animal."
Domestic rabbits lack the instinct of their wild cousins and also do not have the camouflage to survive predators.
"Owning an animal is a lifelong commitment. Dumping it in a park is not only illegal, but completely unnecessary," Gilchrist said.
"There is never a justified reason for dumping your pet."
Besides rabbits, Gilchrist said the society also often get reports of roosters being similarly abandoned in parks frequently.
Auckland Council's animal management team mostly work with dogs, and are not charged with capturing stray rabbits.
But the council monitors the rabbit population at Western Springs, and control is undertaken when required to manage impacts on the environment.