Waikato SPCA is calling for a mandatory night-time feline curfew in an attempt to curb cats mating.
The branch is this week asking the Hamilton City Council to bring in a bylaw to keep cats in their properties between dusk and dawn - a proposal described by cat lovers as "ridiculous" and more suited to dogs.
The agency also wants permits to be required for people to own more than four cats, and for cats aged under eight to be microchipped and registered within five years of the bylaw being introduced. It is also asking the Government to introduce the same rules.
In its written submission to the city council's draft long-term plan, the Waikato SPCA said the rules would address an over-population of cats - one of the most serious animal welfare issues - and stop them being a nuisance.
SPCA national president Bob Kerridge said although it was not national policy, he agreed in principle with microchipping and permits to reduce numbers. But the cat curfew was "nonsense".
"They do it in Australia and it just doesn't work. And what happens there if a cat, whether it's stray, owned or whatever, is found outside after the curfew hour the cat is picked up and destroyed. It's absolutely bloody draconian."
The Waikato SPCA's permit suggestion for households with more than four cats over four months old is similar to a bylaw the Hastings District Council introduced in 2006, barring residents from having more than four cats over six months old on their properties.
Mr Kerridge said this was aimed at stopping a recognised problem.
"You get some people who collect so many cats that they become a bit of a health hazard. So having that in a bylaw is not altogether silly as long as the local authority doesn't knock on everyone's door and say, 'how many cats do you have?'. It should be used only if you have a cat problem."
Cat lovers and animal groups say the Waikato SPCA's idea is purely about money-making, and the best way to control cats would be making de-sexing them mandatory.
Pets on the Net administrator Kim Buchannan and former Humane Alternative shelter manager Norma Capper, who now runs a cat de-sexing programme for community services cardholders, said more affordable de-sexing was the best solution.
Mrs Buchannan said the Waikato SPCA had "totally missed the boat" and the curfew was "ridiculous".
De-sexing had to be "the top thing that they have to bring into a bylaw".
Ms Capper, who owns 10 cats, said the Waikato SPCA "was dreaming" if it thought it could keep the city's cats from roaming the streets.
"You can't fence a cat in like you would a dog. You can have a six-foot-high fence and they will still get over the top."
Hamilton cat lover Simone Brennan, who has five cats and 16 kittens she is seeking homes for, said it would be "terrible" having to lock her cats up at night because they were natural roamers.
She thought requiring a permit for more than four cats was a "great idea" - and said charging $160 to de-sex one cat was the biggest barrier to keeping cat numbers down.
She had "accidentally" ended up with so many cats and kittens because they became pregnant before she had the time or money to de-sex them.