The Mauna Kea hotel is surrounded by many beautiful things, which includes its wonderful beach and impressive golf course. But after night fall, the magic continues when large manta rays come out to play.
The hotel long ago set up some lights to illuminate a portion of the water at night. While I am not entirely sure what the initial aim of installing the lights was (possibly simply aesthetic), the end result was that several large manta rays in the area took a liking to it, which continues to this day. Apparently the light attracts plankton, which in turn attracts the rays.