California Highway Patrol press release: 

 

At an unknown time, between the Saturday May 27, 2017 and the morning of Wednesday May 31, 2017, David J. Dresser of Redway, CA was driving a 2005 Yamaha ATV east on an unmarked Jeep trail approximately one quarter mile west of Barley Road and south of Briceland Road.  For reasons still under investigation, the ATV overturned and Dresser was ejected.  The ATV came to rest on its right side and Dresser was trapped underneath the ATV.  Dresser was located, deceased, on the morning of Wednesday May 31 at approximately 7:30 am by local concerned citizens who were actively searching the area where he was last known to be.

Agencies who assisted with the investigation include: Southern Humboldt Tech Rescue, Briceland Volunteer Fire Department, Humboldt County Sheriff Department and the California Highway Patrol. 

This collision remains under investigation by the California Highway Patrol.  At this time, it is unknown  if drugs or alcohol were a factor in this collision.