While it might be 'unusual” for a council to ask people to stop their cats from roaming, a predator-free organisation says there are good reasons why we should keep them contained.

The Marlborough District Council recently sent a letter Blenheim woman Brenda Green that her cat Milo had allegedly been a nuisance to her neighbour.

The letter says the council's bylaw requires Green to ensure her cat is not a nuisance – which means it's not allowed to roam off the property.

The council says it takes an 'educative approach” to the bylaw and asks pet owners to resolve any issues themselves.

Predator Free New Zealand Trust chief executive Jessi Morgan understands about 20 councils across the country have provisions in place for cats – but often this is in relation to how many cats a household can have, or microchipping and desexing.

Predator Free New Zealand Trust chief executive Jessi Morgan. SUPPLIED: PREDATOR FREE NEW ZEALAND.

Meanwhile, some council's, such as Hamilton City and Horowhenua District, have animal nuisance bylaws. This means any person who owns an animal must ensure it's kept in conditions that did not create a nuisance to others.

Others have bylaws around the keeping of animals, bees and poultry. Dog management bylaws are also common.

'It's unusual that they [council] have asked the owner to stop the cat wandering,” says Jessi.

'In New Zealand legislation cats are really interesting because there's nothing that really captures them, and so I was under the understanding that there's very little you can do about a cat wandering across your property.”

It's why there have been calls from some for a National Cat Act, so that New Zealand has some overarching rules around containing cats.

Jessi says it seems there has been a shift in discussion around what responsible cat ownership means in New Zealand.

'For generations we have let our cats roam … because there's very little that will damage them when they're free roaming.

'Whereas for many countries around the world, their owners don't let them roam freely because they get eaten by coyotes or snakes, or there's other predators that kill them or injure them.

'We're seeing this change in New Zealand where people are realising the impacts that cats have on our biodiversity. But also that it's actually healthier and safer for cats to stay home.”

After going missing, Milo's owner recieved a note alleging he had been a nuisance to a neighbour. SUPPLIED: ANTHONY PHELPS/STUFF.

She says there are some steps people can take in the meantime to stop a cat leaving its property – which will help protect native species.

'Cats are very unusual because they hunt for fun. They don't necessarily hunt for food. So even a well-fed cat will still hunt.

'Now the SPCA actually recommends that when you're raising a kitten that you raise it as an at home cat, because it's the best thing for a cat, and it's the best thing for wildlife.

'Cats have been raised in apartments all around the world for years, and they're perfectly happy, and I think as long as their owners give them lots of pats, and they've got some stimulation they can live perfectly happy lives as indoor cats. It's not unusual.”

-Public Interest Journalism funded through NZ on Air.