This little unit has become my cat's second napping spot. she goes to sleep after slapping the ball (and a little interactive bird that flaps it's wings and chirps) and together they keep her entertained for hours. She wants the ball on and moving around in the plastic cover as soon as she gets breakfast, which makes the bird wake up and chirp, and she is a happy camper. We then chase around the house with a long string on a wand with bird feathers and a plump mouse shaped bird I added that had fluffy feathers, and I found a real bird feather on my porch from a pair of doves that come twice a year, so, even though you aren't supposed to keep feathers, I used it to rub a bit of bird scent on the other feathers and then replaced the real one where I found it. I'm in the city anyway and city sweepers sweep the gutters moving molted feathers every spring and summer anyway. Just be cautious about the kind of bird, starlings are not protected but most others are. Pigeons feathers are fair game along with seagulls if you have them around, which we do have a few. If used to just rub a little realness on an interactive toy or a feather toy and then placed back where you found it in your yard I doubt if it hurts anything. I'm very cautious as I rehabbed birds for a few years for the fish and game. And I think in some places they don't really care, unless it's an endangered species that's suddenly shown up somewhere it wasn't before. Anyway, to continue, this thing is a fascinating adjunct to a number of interactive toys, the ball and the bird are rechargeable and come with their own USB cables, and they last for a few days at time before running out of juice. Takes about an hour or so to recharge. This thing is a wonderful treat for my 2 year old cat. She's new here, only been with me about 5 weeks, but settling in and with the toys she's feeling very happy and welcome, flops on her back to sleep, rubs her cheeks on everything I give her and everything in the house, so she must be happy as she is marking these toys as hers. Great ideas, keep them coming. I'm going to buy more of these interactive toys. She carries them everywhere, flappinig fish, chirping bird, whistling lizard with a long tail that moves up and down, these Migicat toys are great. See more reviews on other stuff as I collect more. Very affordable as well.