The Black Hole of South Andros Island, a vertical cave, was filmed by Beyond Production out of Sydney for Animal Planet.  This was the second trip in for me, although the film, for filming reasons state that this was the first time in.  A new species of bacteria was discovered and named after my late husband, Rob Palmer.  It is a bacteria that is responsible in part for giving these particular types of caves their colour but also for generating the extreme high temperatures at the 17.8 metre depth where the one metre thick layer, estimated to contain 5 tons of dry weight bacteria, live.  This is the largest vertical system we are aware of in the Bahamas.  It can be seen from space.
The Black Hole of South Andros, Bahamas
Beyond Production, Australia
Part 1 of the film is the first URL address and Part 2 is the second half of the film.  The film had to be split because of the length (15:20)