Thanks.I think it is inferred since TNG episode dialog indicates 1701D is adequately protected from laser by nav shield alone, and 1701D was in full stop at the time.
I looked it up, The Outrageous Okona. When Picard talks about the nav shields alone stopping lasr fire, the ship is moving. (He asks them to reduce speed shortly after that.) Also putting a dent in this one, even if the Enterprise was explicitly shown to always have nav shields active, it doesn't mean a Bird of Prey operates the same way.