A catio (short for "cat patio") is an enclosed outdoor space that lets a cat experience fresh air, sunshine, and the sights and smells of the outdoors, without the risks of roaming free. It's one of the simplest changes a household can make that's good for birds and good for the cat.
Free-roaming cats are the single largest human-caused source of bird mortality in the U.S., ahead of window strikes, vehicles, and every other human-caused factor combined. That's not a knock on cats, it's just what happens when a skilled natural predator has unrestricted outdoor access to a landscape full of nesting birds.
It's not one-sided, though. The outdoors is dangerous for cats too. Indoor cats live an average of 10 to 15 years, according to research out of UC Davis, while free-roaming cats average only 2 to 5. Vehicles are the leading cause of death for outdoor cats, and here in the Conejo Valley, resident coyote and bobcat populations, along with great horned owls and red-tailed hawks, all pose a real risk to a cat left outside unsupervised.
A catio gives your cat the enrichment of the outdoors while removing nearly all of that risk in both directions: birds are safe from the cat, and the cat is safe from cars, predators, and disease exposure from other animals.
Catios scale from small and simple to elaborate, and there's a workable option for almost any home: