A law-enforcement airboat is due to appear in Grand Theft Auto VI, shown in an official screenshot pursuing poachers in a Bison alongside two POACH SUVs and a POACH Maverick. Essentially the civilian Panther-style airboat fitted with a lightbar above its fan cage, side stripes and a hull logo, its equipment and context imply operation by the POACH wildlife-protection agency.
Vehicle data via GTA Wiki (Fandom), CC BY-SA 3.0.