RedactedNarrative: Vessel 1 and Vessel 2 were both travelling east in Bayou Jean Charles.  Vessel 1 was forward of Vessel 2.  Vessel 2 then attempted to overtake Vessel 1 on Vessel 1's port side without signaling his intention to pass. As Vessel 2 was overtaking Vessel 1, Vessel 1 made a course change to port to enter an intersecting  bayou without himself signaling his intention to turn, nor insuring that his course change was safe to perform.  Vessel 2 observed Vessel 1 turn to port, but was unable to stop nor alter course in time to avoid colliding with Vessel 1. Both vessels were remotely steered and both had the appropriate number of PFDs on board.  Neither alcohol nor drugs are suspected as a cause of this accident.