There was, however, an in-universe explanation. Ultimately, as seen in the finished film, the Bird-of-Prey in The Search for Spock was simply a Klingon Bird-of-Prey, with any mention of its origin or its theft from the Romulans left completely omitted. However, as the script developed, the Romulans were swapped out for Klingons and the once proprietary Bird-of-Prey became a stolen one. Early drafts of what would become Star Trek III: The Search for Spock, in fact, featured the Romulans as the film's villains and fittingly contained references to their ship as a Bird-of-Prey.
