Police are concerned for the welfare of an experienced bushman who has been missing in the Kimberley for four days. David Lawson, 41, has been missing from his Dampier Peninsula property since the weekend. A helicopter, fixed wing aircraft, SES volunteers and local rangers on quad bikes have joined the search. Mr Lawson is an experienced bushman with good survival skills, but it is highly unusual for him to go missing for an extended period without contacting family.