Feeding hummingbirds is a popular pastime for many gardeners, who hang hummingbird feeders containing sugar water outdoors close to their windows for easy viewing. One of the drawbacks of hummingbird feeders is ants, which are attracted to the sugary solution and can clog the feeders.
To prevent ants from competing with your hummingbirds for the sugar water, try placing moats on top of the feeders. Moats come in different shapes and sizes. Simply fill the moat with water and hang it on top of the feeder. Ants can't swim, so they won't be able to reach the feeder. Periodically clean debris out of the moat so the ants don't create an ant bridge to the feeder over their dead comrades.
For more information on ant moats for your hummingbird feeder, go to: Lee Valley Nursery.