How to keep ants out of your hummingbird feeder without poisons: 1. Take the lid of a water bottle and use a hammer and nail to make a hole in the middle. 2. Slide the cap, open face up, down the wire cord. 3. Put poster putty between top of hummingbird feeder and water bottle cap to create a seal. 4. Fill cap with vegetable oil. The ants can't swim through the oil, thus keeping them out of the feeder. I've had this set up for a week and still ant-free!