Authorities in New Zealand raised concerns Thursday about a student drinking game called "possum", in which participants sit in trees downing alcohol until they fall to the ground in a drunken stupor.
The craze has reportedly swept the South Island city of Dunedin, which has a large student population, leaving public parks strewn with glass, litter and vomit.
"It's been occurring fairly regularly for the last two or three years," Dunedin City Council's parks manager Alan Matchett told Fairfax Media.
Matchett described the activity as "pointless" and said his staff were tired of cleaning up the mess created by students playing possum.
"What they drink has to come out again, so they do throw up and urinate from the trees," he said. "Obviously, it's not nice to have that left behind."
He said the council was concerned about potential injuries to students and damage to its trees, as well as the inconvenience to other park users from boozy youths nestled in the branches.
The game is named after the brushtail possum, a nocturnal marsupial introduced from Australia which has become a feral pest in New Zealand and is a common sight in urban parks.
Dunedin's University of Otago said the practice was against its code of conduct for students.
A university spokesman said any students caught engaging in the possum game were forced to clean up their litter and faced the prospect of further disciplinary action.