My family visits the Padre Island National Seashore every summer. I'm also very interested to find the frequencies used there. Are the 166.900 (output) and 166.300 (input) the only known frequencies used by the NPS employees at this Seashore? For example, the Park Rangers, the Turtle Patrol ATV's, and other park operations. There is a tower next to the Malaquite Visitor Center with an impressive VHF array. However, the Turtle Patrol ATV's have UHF mobile antennas.