"Whoever did it [on the Routeburn Track] walked from the Glenorchy end to the Divide - they [the tags] are all on one side."
Doc believed the person responsible had tagged the track on April 19 or 20, at Franz Josef between April 23 and 26 and in Tuatapere last weekend.
Mr Lind said there was a possibility a copycat tagger was involved in some of the vandalism, or that the person responsible had been spurred on by publicity.
"Taggers like publicity ... Any publicity they're getting is really good for them [but] it's just vandalism as far as I'm concerned."
The wider community had expressed "severe disappointment" about what had happened.
Mr Lind said staff had spoken to all but one of their leads - Mr Lind was following that lead up with police.
The person responsible could be charged under the National Parks Act 1980 with wilfully damaging or defacing a fence, building or apparatus; or unlawfully altering, obliterating or defacing signs and marks, including boundary marks.
The maximum penalty under the Act was three months' imprisonment or a $2500 fine.