Near as we can tell this pair of parakeets were four or five years old when my daughter adopted them from an older couple who went into a nursing home, and she had them a year, and I've had them almost seven years. They were on the porch last summer...in a cage...and one was lost to a predator. I suspect a feral cat that I see once in awhile. The chihuahua and the pugs are cat friendly so Bella is to have a job keeping it away when she grows up. I won't put the remaining parakeet outside, but I have chicks.
I don't know how long parakeets live but it has been my experience with other family members that a year or two pretty much did it before they died of something. I have a friend who had one more than eight years who went to great lengths to take care of it...including taking it to the vet to set a broken leg. I suspect mine lasted so long because they are never outside the cage. My oldest Pug...Blossom...hates birds. She is pretty old and slow, but Bibette would be on it in a second if it got loose.
I took the pair of parakeets who came with this huge cage because my daughter was moving. I really didn't have room for them in my tiny Florida house but she says 'you know parakeets, they don't last forever anyway'....well, that was seven years ago. But...I made a lifetime commitment to the little thing.
Terry in Tennessee