Change the law around free roaming pet cats so that all free roaming pet cats must be neutered. I also think rescue centres should be given powers to charge pet owners the vet bills that come with un-neutered cats fighting and mating.
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I work tirelessly along with many others to try and help cats and kittens on the streets. By changing the law that all pet cats that free roam must be neutered, I believe rescue centres can focus their attention on feral colonies and getting the population of feral cats under some sort of control.