Stalking birds

My cat is stalking birds out by the bird feeder. Its been pretty cold so the birds had gone but the last few days turned out to be warmer than usual and we have some chickadees frequenting the bird feeder. My can noticed and has been sitting out under the feeder every day, hoping they don't notice. I'm hoping they do notice, play it safe, and stay out of his reach.

My cats never go outside, but they love to watch birds through the glass patio door. If a bird gets very close, they even attempt to catch it. It's an instinct they have, they are little hunters.