I found a quaker parrot over a year ago that is a mental plucker. He has a full-size play tree, a huge cage, a stand in each room, lots of toys and foraging things for his enjoyment. He has the best pellets, lights and supplements for his health.
The experts think he was abused, which started his plucking, and he will not stop unless he is collared. I feel this would cause him to have severe depression and have avoided collaring him. Will he eventually pluck more and die from it?
Feather picking might be a symptomof an illness.
I assume that by identifying your quaker as a “mental” feather picker, you presuppose the origin of the behavior is psychological instead of medical. You mentioned the opinion of “experts” but I cannot agree they are experts from what you have said. Asserting that a parrot was “abused” because it is a plucker is not valid, from my experience.
Most experienced avian veterinarians and parrot behavior consultants believe that a huge percentage (if not all) cases of feather destruction begin with a physical problem, such as malnutrition or illness. So it is not correlative that feather destruction has anything to do with so-called “abuse.” I have worked with many feather-destructive birds that have happy and enriched lives, so that is an invalid assumption to make.
That said, there are certainly cases where the physical origins of a behavior like feather destruction have resolved, but the behavior continues due to secondary reinforcers. Those secondary reinforcers can include the attention they received from their owner for doing it, or something self-rewarding, such as a comfort or self-soothing behavior (like a person’s nail-chewing habit).
Take your quaker to an experienced avian veterinarian for a full work-up. Testing can help an avian veterinarian rule out things like heavy-metal toxicities and systemic disease, both of which can predispose a bird to its damage feathers. Without this information, you cannot assume your bird is healthy.
I agree that collaring your quaker could result in severe depression, as I have seen that a number of times. If there ever was a case of “learned helplessness” in parrots, it the bird that is forced to wear a collar. The other problem with collars is that they usually do not work in cases where a behavior is likely a well-entrenched habit, which is likely the case with your quaker parrot.
I do not, however, believe that he will “die of plucking.” I worked in avian medicine for 20 years and never saw a parrot die from damaging feathers. True, they can get chilly if the surroundings are cold, but a healthy, nutritionally strong parrot is not going to get sick simply because its environment gets a tad nippy. That myth was based on the feeding of an all-seed diet; the parrots were dying of malnutrition, not a lower room temperature.
It is also not a given that feather destruction always progresses into self-mutilation. A bird that self-mutilates is literally ripping out chunks of its own flesh, so it has nothing to do with feathers. But even severe cases of self-mutilation rarely become life-threatening. While some birds do both, many of the self-mutilators I have worked with were in perfect feather. Veterinarians might lump them together, but that is because they both fall under the category of dermatologic or skin problems, not because they automatically happen together.
Get your little friend properly vetted and deal with whatever (if anything) the avian veterinarian finds. Enjoy your lives together to the fullest; he obviously lucked out when he found you!