Answer
Create a persistent custom Text field, around 100 characters, on the Transport Task Logical Unit, and set its default value to a session/user-identifying expression such as fnd_session_api.get_fnd_user() (or an equivalent user-ID substitution token). This automatically populates and persists the creating user's ID directly on each new Transport Task record at creation time, letting it be queried and filtered on directly going forward, rather than relying on the less-efficient History Log report to trace back who created each record.