Australia wants to force cats to stay inside or give them a curfew because they are murdering so many other animals they are a threat to the country's biodiversity

I mean, if such a campaign is ever completely successful, along with one for capturing or fixing stray and feral animals, there would need to be some amount of breeding of them or they'd eventually go extinct. Perhaps with regulation on both practices that lead to unnecessary health problems (like inbreeding or breeding for harmful traits like squashed faces) and on numbers to avoid breeding more of a specific sort of animal than there exists demand for.

Are you confusing 'breeder' with 'pet mill'? Ghetto breeding was horrible to my family involved in animal care and salvation. Actual breeders, though, not so much.

Domestic cats have been in the UK for _{2000 years, and wildcats for >}8000 years.

Their only real predators in the UK are cars and dogs, and most British bird species are well acquainted with cats, and on the whole aren't at high risk. Recommendations say an outdoor cat is a healthy, happy cat.

The RSPB (bird conservation charity) doesn't find them a major problem here, but do recommend:

1. Neuter them
2. Keep them in at dawn, dusk & night
3. If they ever kill a bird, put a bell or beeper on the collar

Which seems a reasonable set of recommendations.

On the other hand, the USA and Australia don't have the thousands of years of history of cats as part of the ecosystem, and they have all these wild dog-type-things and snappy reptile things etc, so the cats are in more danger, and the native bird species are at higher risk. Recommendations say an outdoor cat is a bird-murdering machine that's about to get run over by a giant SUV and then eaten by drop-bears.

My Eastern European neighbours think it's weird that we let the cats inside at all. They think they should live entirely outside.

So I guess "different countries, different rules".

From a UK perspective, it seems unbelievably cruel to keep a cat locked indoors. The hunting instinct is one of a cat's main drives, so to take that away is equivalent to removing sleep or food. I understand the issues around cats and wildlife in other countries, but I think the solution is to just not have domestic cats rather than trying to imprison them.

Partially. It also relies on the cat listening to the owner when they try to get them inside. Some cats will, but most come when they feel like it. "Like herding cats" has its meaning for a reason.

Pets in general shouldn't be allowed to roam freely outside. There's too many dangers to them and things they can do to cause problems.

Feral cats aren't pets

What if the rodents are not indigenous and are more of a pest than the cats?

I think the first step is to identify the full impact of Glysophates and other similarly used pesticides, particularly their roll up impacts, then we can start working on secondary effects like cats.

If you take away the cats, rats and mice will destroy 10x more than cats ever could. See Vancouver BC or Easter Island.

I am suggesting no such thing? What I mean is that humans should start doing other things first, clean up their own shit - first reason that there are so few birds is factory farming - overly aggressive use of pesticides killing off insects, machine harvesting chopping up ground nests, land “purchase” destroying forests and animal trek transit zones. Outdoor cats come only in sight because of the one animal kind that does thrive on this: rodents, especially mice.