Outdoors! (but not fanatic about it)
I'm allergic to cats, so any cat I have is, necessarily, going to have to be a cat that spends 100% of its time outdoors (if you count sleeping in the back shed in cold weather as outdoors.)
I keep saying I'm not going to adopt any more cats, but my plans don't work out and I keep ending up with more cats, and here's why.
I live near the edge of the woods. Idiots from the city adopt cute little kittens, then when the kittens reach six months to one year of age, they aren't "cute" anymore and the city idiots come here to dump them, thinking the cats will be "just fine because they can live in the woods and hunt."
The cats are NOT "just fine."
Most of the dumped cats are dead within days - they are clueless at how to defend themselves and dogs and coyotes and cars wipe them out. But once in awhile, a survivor makes it to my doorstep, hungry and desperate and sometimes injured.
I can and do try to find homes for the dumped cats that arrive at my house but, realistically, these are older "non-cute" cats that people aren't very interested in adopting.
So the cats who arrive on my doorstep as strays/dumped cats have, realistically, the following options: (1) if I don't intervene in their lives, they'll end up as feral cats, with short miserable life expectancies; (2) if I take them to the animal shelter, there's a better than 50-50 chance they'll be euthanized within thirty days; or (3) I can keep them as part of my crew of outdoor cats.
So I generally have 2-4 cats and all of them spend 100% of their time as outdoor cats.
Their median life expectancy is around five years but what happens, in fact, is that about half the cats disappear mysteriously presumed dead at approximately age one year (which corresponds to the late teen years in humans) and the other half learn how to take care of themselves and usually live a normal life span of 8 to 12 years.
I had one 100% outdoor cat that lived to be 16 years old and eventually died of geriatric kidney failure (after three months of subcutaneous fluid injections!)
I'm not a fanatic on the indoor/outdoor controversy. I think people have to be realistic about what choices are available for the cats and whether their own situation makes it more practical to have indoor cats or outdoor cats.
And it's important to recognize that domestic shorthairs typically have a strong impulse to roam and a strong desire for freedom. Although many cats can live happily indoors, the fact is that many cats simply do not adapt well to indoor living and better a short outdoor life than a miserable indoor life (also, MUCH better to have a short outdoor life than to be euthanized as "unadoptable" due to "behavior issues.").
For people who want a 100% indoor cat, I recommend Persians, they seem to have a low key temperament and relatively non-intense roaming instincts, so they do particularly well indoors.
I have a considerable amount of sympathy for bird lovers who detest feral cats. Judging by my observations, feral cats don't have particularly desirable lives.
And they do slay a lot of wildlife while trying to survive. I would support humane euthanasia of feral cat colonies in order to protect the birds, especially where the feral cats are chowing down on rare birds instead of common house sparrows.
I hope the bird lovers will, however, be willing to tolerate the occasional small colony of feral cats (especially if well maintained and not eating endangered species!) and will be realistic about the hunting habits of outdoor cats that are domesticated and have a regular food supply.
Bird lovers who study the issue will find that approximately 2/3 of domesticated cats are non-hunters and the ones who do hunt will hunt a couple of times a week but will kill lots of things - rats, mice, bugs, lizards, snakes - not just birds. (We can be pretty confident about this because scientists place kitty cams on cats to find out what they do when they aren't asleep on the porch, and this is what the results show.)
One of my cats once killed a half grown copperhead snake (VERY poisonous) and placed the body neatly curled on my porch as a gift, which startled the heck out of me. That cat may have saved the lives of my children! So it can be a VERY GOOD thing to have an outdoor cat that hunts.
I've written more than I meant to, but I think people get a bit fanatic on the issues of indoor cats/outdoor cats/feral cats/TNR/birds and I think we could all benefit from being less dogmatic and more realistic.