The problem is, cats and dogs are predators, and humans tend to congregate these predators together in numbers that are not at all in balance with the ecosystem around us. That makes it very, very difficult for little song birds to survive in our gardens.
I live with several cats, and love them all. What is more, I have many neighborhood cats visit my garden often. And there is a stray cat who lives on my porch. Although my cats all live indoors, some of them like to go outside, and usually have free reign. But, not today. Today I have babies fledging all over my garden. And so my cats will all be indoors now, until the babies are all able to take care of themselves out there. They get extra treats, and extra attention, and do not seem to mind. Even my porch cat, who does not care for the other cats or the dogs in my home, had to come in. He's staying in the basement for a few days. (All the cats who go outside, including this one, have bells on their collars, to protect the birds. But even the bells are not enough to prevent them from being a danger to baby birds. So all of them must come in for now.)
I have been carefully watching my garden, keeping neighbor cats out of it. And when I find one who simply will not go away, I put a collar with a bell on it and take it home, explaining to its humans how hard it is for birds to survive in neighborhoods filled with cats. Usually, they are very receptive to this gentle education.
So I'm asking people whose families include cats (or outdoor dogs) to please think about this. No, I'm not anti cat. Far from it. I love cats. And I love birds. My cats get lots of great food, and do not need to be terrorizing the birds out there. I bet the same is true for yours. Please be good to bird babies and bird mothers this spring, and make your cat friends comfy inside for a short time, during this important period in the development of birds.