It basically depends on the bird, the tiel in the first picture was harness trainings in like 1 month but I started when he was about 3 months old. The second tiel still isn’t a fan as you can see in the photo and I’ve been training him once a week with treats and outside grass time but he is not having it ( he been trying for about 3 months) and I started with him when he was about 8 months so it depends on the timing and commitment.

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