It's basically impossible for another Prehistoric Park to happen. Nigel wanted it, but the producers didn't. Even after the first 6 episodes, it was intended as a stand alone show. It wasn't really a question of "wait to see if it does well," it was more that it was done and dusted once the last one finished.
However, Nigel himself is still interested in Prehistoric Animal wildlife presentation. He's said in multiple interviews, even up until now, that he is pitching ideas around to various producers. It's definitely possible (fingers crossed) that we'll get more of him in prehistory, just not Prehistoric Park.
