Was re-watching every episode of the first season and suddenly he had a bunch of Tauros. I was like "when did this happen?"
Ash caught his Tauros in Episode 35, however the episode was banned in many countries
This episode was banned due to the prevalent usage of handguns throughout the episode. Kaiser, the Safari Zone warden, points a gun at Ash's head a couple times, and even shoots the gun at Team Rocket at one point. The banning of this episode left a major plot hole and a continuity error in the English dub, as this was the episode where Ash captured all 30 of his Tauros. As this is the Safari Zone episode, it also makes the Safari Zone unseen in the English anime, though it is mentioned in the two episodes that took place before it.