Parrots tend to soak and soften certain foods in water (especially pellets), they may defecate in the bowl, amuse themselves by adding paper or cage litter to it, and without options they might bathe in the water dish and count on their rinsing and cleaning their beak after every snack.
Sanitize or Colonize: A bird’s body, much like our own, harbors numerous micro orgasms, many of the bacteria which exist in the body are harmless, some are beneficial but other may be pathogenic. The problem is not the presence of these organisms but rather the population. A polluted water bowl is an ideal medium where bacteria will thrive and multiply rapidly, under such favorable conditions a colony can double in size every 10 minutes. When a pet bird drinks water from a contaminated source the risk of a bacterial infection increases exponentially.
The issue for pet birds is more than providing a sufficient supply of potable water; it also means keeping both the food and water vessels clean. Too many bird owners simply rinse the water bowl and refill it, that’s just not good enough. Food and water dishes need to be washed daily, (with hot water and preferably an antibacterial soap).
Bathing: Given the opportunity birds are immaculately clean creatures. Bathing improves skin and feather conditions, promotes natural preening activity and is just plain fun. Every individual has his or her preference when it comes to a bath. Some birds like a mist bath, some love to immerse themselves in the shower and others may favor a shallow dish to splash around in.