Echoes From the Deep

The first human and dolphin colony team has arrived on Epsilon Eridani 2, a planet that was once inhabited by a highly advanced species that has gone extinct.
On this exciting new world, the humans have brought all of their typical problems with them, while the dolphins adjust quite easily to their new home.
All of this changes when bizarre events begin to happen to the colonists. Is the stress of a new colony causing unknown neuroses and psychoses to suddenly surface? Is there something in the atmosphere that the colonists didn't know about? Or is there something else behind the bizarre occurrences?