Parakeets, also called budgies, are relatively peaceful birds, but sometimes they do fight. Whether it's over territory, because one budgie is afraid of the other, or just because one bird is irritated, battles can get loud and affect your pets' health. If you can predict the likelihood of your parakeets deciding to have a battle, you'll improve your chances of a happy cage. One method is to pay attention to the sex of your birds.
Fighting among budgies can be as minimal as occasional squawking, or as serious as full blown harassment. Problem parakeets can stress out others in their cage, causing bald spots from pulled out feathers, low weight and health issues. Check over your parakeets regularly to make sure that they're all in acceptable condition. Keep an eye on any fights to make sure they don't get out of hand.
Fighting, whether it's between members of the same sex or members of opposite sexes, serves a purpose. Budgies need to establish a “pecking order” among cage mates. In nature, these birds live in huge flocks of hundreds or even thousands. Establishing the social order helps them stay happier in the long run, but there may be some squabbles along the way. Not all fights are serious–some are just helping establish social order.
Female budgies are more likely to be territorial than males, though male budgies do sometimes fight over cage space. These birds perceive their cage as a nesting site, and are guarding it against trespassers. Fights between birds of the same sex are more likely than fights between opposite sex budgies, though. Males commonly fight for the attention of a female in the same cage. Some very territorial females will try to fend off any budgie they meet, even males.
Territorial or stressed budgies may not stop at biting one another and pulling feathers. They can also extend their territorial behaviours to you. Simply opening the door may cause a stressed parakeet to bite you. If your birds have been fighting, approach the cage slowly and never take the bird out. Instead, allow your budgie to step out onto your hand. Most territorial budgies are quite docile outside the cage.
Fighting is more likely to happen when you introduce a new bird, rather than between birds that have known each other a long time. Introduce new budgies outside the cage, or in their own separate cages. Open both cages to let the birds get to know one another. Only when they've become able to deal with each others' presence should you allow them to share a larger cage. Include two food and water dishes and two of each toy to discourage squabbling.