To attract the most birds to your bird bath, you’ll want to keep it full with water at all times. However, you’ll want to dump out the water every day or two to ensure your birds have fresh, clean water to drink and bathe in. This will help to keep your birds happy and healthy, as illnesses can be spread via contaminated water. "You should clean and disinfect your bird bath at least once a week, but as often as possible is best, especially during migration," says Lauren Ross, Lifesaving and Care Specialist/Wildlife Rehabilitator at Best Friends Animal Society. "Diseases like salmonella, trich, and conjunctivitis can all be spread species to species, so disinfecting your bird bath as often as possible can help reduce the risk of spreading these diseases between flocks."