After two years, it's probably become a habit.....back in 1997, Dr. David Spiegel, of Petpsych.com, wrote: “…..as twisted as it may seem, by plucking their feathers, they have a reliable way that they can control and deliver feelings of pleasure to themselves. They have essentially learned how to access their body’s drug supply system, though they invariably pay a high price in the damage that they inflict upon themselves.”
He was talking about endorphins.....the natural pain relievers produced by the body. They are chemicals that calm you, relieve pain and make you feel good. Endorphins have been likened to the opiates of opium, codeine, morphine, and heroin.
Citing P. Jensen, from his work Stress I Djurvärlden. LTs förlag, Stockholm, Sweden (1996), Yasmine A. Bengtson, in her Master of Science thesis writes:
“Under-stimulated parrots have been observed biting their own feathers, not as in grooming behavior, more in self-mutilation….. Gorillas in zoos turn their backs on visitors and eat their own droppings. Mutilation and cannibalism can result from under-stimulation. Jensen (1996) suggests plentiful supplies of fresh hay to distract from this behavior, while the smell and taste of blood intensifies it.”
Although the study on endorphins continues, very little published data has filtered down to the average bird owner, so, getting suggestins you get another macaw could easily subject a non-plucking macaw to a habit it doesn't need.....you say "During the day she has our cats to amuse her and the stereo . She has new toys to keep her busy....."
But what do you do to stimulate and interact with the bird? Macaws, more so than other birds, need stimulation & flock interaction but then I'm not an animal behaviorist.....You & all other humans in the house are the bird's flockmates and if you're not providing stimulating interaction, the feather problem could very well stem from that.....
Good luck.....
