The sweet nectar in your hummingbird feeder is just too tasty for ants to resist. Several methods can keep ants out of your hummingbird feeder. Some of these methods, such as adhering duct tape or Tanglefoot to the feeder, can harm the hummingbirds themselves. The safest and most effective way to keep ants out of your feeder is to install an ant moat that makes it impossible for the ants to crawl down to the nectar. Some hummingbird feeders come with a moat already installed. Crafting an ant moat, however, is almost as easy as buying one--and less expensive, too.
Cut a 6-inch length from the long bottom section of a wire hanger with wire cutters. Discard the rest of the wire hanger or save it for use on other hummingbird feeders.
Hold one end of the cut wire with pliers. Heat the other end over an open flame (or rest it against an electrical oven burner) for about 20 seconds.
Run the heated end of the wire hanger section through the center of an aerosol spray can top to create a hole in the center of the top. A spray can top that is about 3 inches in diameter works best, such as those you find on cooking spray, hairspray or paint spray cans.
Thread the wire through the hole until the top is centered along the wire.
Use a hot glue gun to seal the gap between the aerosol can top hole and the wire. Put a sufficient amount of hot glue on the top and the bottom side of the cap. Allow the glue to dry. Fill your moat with water from the kitchen sink to make sure it is watertight.
Detach the hummingbird feeder from the hanging fixture. Take your pliers and create a loop that attaches the bottom end of your wire hanger ant moat (the aerosol cap should be facing up like a cup) to the bird feeder. Create a second loop at the top of the wire hanger that affixes it to the hanging fixture.
Reattach your hummingbird feeder to the tree or stand if necessary. Fill your moat with water. Any ants crawling down the wire will not be able to get any further than the moat.