Coastal Marten Extant Population Areas (U.S. Fish and Wildlife Service, version 20180206)
The following is an excerpt from the U.S. Fish and Wildlife Service species status assessment report for the coastal marten (Martes caurina), Version 2.0 (July 2018); refer to this report for additional details: 

4.2 Current Range and Distribution (1980–current)

All current (since 1980) verifiable marten detections …