Department of Conservation Wakatipu area manager Greg Lind said the same tag seen along the 32km Routeburn Track had been reported at the Franz Josef Glacier access facility and the Wanaka skate park.
Yesterday afternoon staff at the Hump Ridge Track said the tag ''Rowdy'' had also been found outside the office in Tuatapere at the weekend.
Mr Lind said suspicion had fallen on a group of school pupils visiting from Australia, but the party had been ruled out, as it did not visit the West Coast or Tuatapere.
Public feedback had been extremely helpful in building a timeline, he said.
''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 of a copycat tagger or that the person responsible had been spurred on by publicity.
''Taggers like publicity ... [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 and he was following up that lead 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 is three months' imprisonment or a $2500 fine.
