I'm going to be up front, I am kind of an animal rights nut and have been a very proud vegetarian for 14 years. I am personally pretty biased on the subject of keeping exotic animals in most cases, FYI. That said, I feel there are a choice few reasons that it is acceptable for us to remove animals from nature. A big one is there are some very well-run captive breeding programs designed to increase wild populations of endangered species by releasing offspring into the wild. In this case, human intervention is actually helping fix the problems we've created for these poor creature by destroying their habitats, harvesting them for food, and especially in the case of birds and reptiles, removing them from nature for our own enjoyment as domestic pets. Another sound reason for removing animals from nature is bringing injured specimens into an appropriate captive setting to give the individual a second chance at life as well as giving the public an opportunity to become more educated about the wonderful species we share this planet with.
Specifically in regards to parrots, I honestly feel we were wrong to ever take them out of the wild to begin with, and now were left to deal with downward spiral we've created for these beautiful animals. We, as a species, singlehandedly decimated their wild populations in less than a century, ruined much of their natural habitat, and repaid them by putting them in every chain petstore around the world for uniformed morons to take home and neglect. Many of the most commonly neglected parrot species you see in domestic homes or that have ended up overcrowding shelters are the most critically endangered in the world. Yet, there are thousands upon thousand who are unable to be released to the wild because they are dependent on human care, yet there's very few humans willing to actually give them a forever home. Then breeders keep on breeding them for domestic homes, more people with no experience or dedication take them home on a whim and get rid of them a few years later, furthering the problem. It's so very sad to see. As much as I wish this never came about in the first place (removing parrots from the wild), it did, and it's very important for bird lovers to be educated about adoption vs. buying babies and supporting breeders. Parrots born into captivity who are not in a dedicated wild release program will never be able to be released to the wild. That leaves those of us who have a true love and understanding of parrots to pick up the pieces and give these birds as best of a life as they can have. I don't disagree with people adopting parrots, and giving a bird who can never be wild a home, but I do seriously disagree with the continuation of breeding them for domestic pets as well as the (now) illegal wild-caught bird trade. Another forum user has this on all her posts (not trying to plagiarize your quote, I actually really love it!) and I think it really sums up what we've done to parrots- "we remain forever responsible for what we have tamed".