For some reason on Ark Mobile, it does not allow me to shoot off an Argentavis when grappled. I think that is a bug on my phone. Anyways, I found the easiest way to get a Quetzal is to ride a Tapejara with multiple seats on the saddle, and then go to second seat. When you do this, shoot the Quetzal and use the spy glass to target him. If you keep shooting the Quetzal while it runs, you should not have to whistle passive for your Tapejara. Then, grab some meat and a lot of bio toxin. Boom, you have your new Quetzal.

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