Yes, a collar with a bell reduced predation by cats, and is recommended by the Royal Society for Protection of Birds, among others.

Now, to be fair, it is not without its cost. It happens that cats get it tangled in fences or other obstacles and die by strangulation or predation.

You can put a wide-ruffled, brightly-colored collar (with a bell) on the cat. My wife found one on Etsy for our little fluffy hunter, and the combo of noise/color allows the birds to hear/see him coming and skedaddle.