When it comes to expressing boredom, cats are known to make full use of claws (on your furniture) and other forms of self-expression like peeing in the middle of your bed every night. Which is why it pays to look for a cat-friendly apartment.

"When I first moved to Brooklyn," shares an enlightened cat-owner on the Q&A site Quora.com, "my apartment didn't have ledges for the cats to look out the windows and the street didn't have any trees for birds. Barren Bushwick. There also wasn't any activity outside like people & families, just an auto body shop, so my cats were bored."

Later, she says, "I moved to a place where I made sure the windows had wells, there's a vibrant backyard with a huge tree outside visited by sparrows, cardinals, even a couple of hawks; where out front is a tree lined street with people, to watch, cars, noises, and more birds, my cats have been much happier. And they're just indoor cats."

Another tactic for keeping indoor cats happy--or smoothing the transition of an outdoor cat to indoor apartment life--is to enrich the cat's indoor environment with a changing landscape of toys and opportunities to explore.

"Cats love vertical space, so buy a large scratching post/tree," Interactive toys were recommended, too--either storebought like Da Bird and Cosmic-brand cardboard scratchers, or homemade, as in feathers attached to a long stick or rolled up balls of newspaper, which are "light enough to bat around and easy to pick up in their mouth."

Another idea: Find a large box, "cut one or two paw-sized holes in it and toss a fake toy mouse in; then change it up, take the mouse away, then give him another toy; take the box away for a day or three, then give him another box of a different size." You get the picture.

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