Steps on how to tame a argentavis:

1. Build 4-5 stone gate frames place them in a straight line place then distant but not to distant or the Argentavis will fly through the top, build 2 reinforced gates and place one at the end leave the other one in your hot bar.

2. Get the argentavis attention, make him follow you into the trap and place the other gate then run through the side.

3. Use around 50 tranqs just in case you miss

Use a primitive crossbow.

4. There carnivores so they eat meat mutton/prime will work or kibble if you have!

There is a easier way to do this.

Just shoot the bird while he is following you when his torpor starts to get High he will try to fly away so trap might be better whichever way you prefer! -Boycicle