Retreating glaciers possible threat to tourism
The rapid retreat of glaciers is raising concerns about the multimillion-dollar West Coast tourism industry.
University of Canterbury geography lecturer Heather Purdie said the glacial retreat was making access increasingly difficult for guided walks at the Fox and Franz Josef glaciers.
But the growth of the glacial lake at the Tasman Glacier was increasing tourism opportunities there, she said.
Fox Glacier's most recent advance had ended in 2008-09, and Fox and Franz Josef were now drawing increasingly close to their previous minimums.
Coupled with thinning, that indicated the retreat would continue for the near future, Purdie said.
"Adaptation to changes associated with retreat, like steepening ice slopes and increased rockfall, includes the increased use of helicopters to access flatter parts of the glacier."
Shortening glacier length could be compensated by extending access tracks up valleys, she said.
"But such solutions come at a cost, not only in monetary terms, but also in terms of increased environmental disturbance, and negotiation to establish acceptable degrees of adaptation will be ongoing."
While tour operators faced challenges, interest in glacier tourism was increasing, with up to 400 tourists a day guided to the glaciers last summer, Purdie said.
Fox Glacier Guiding chief executive Rob Jewell said it was necessary to take a long-term view.
The glaciers had advanced from 1983 to 2008 before going into a neutral phase and then retreating.
"There are challenges at present. We have to be innovative about how we access the ice, which we are doing," he said.
A tour that combined a helicopter ride and walking was proving highly attractive to the growing Chinese market.
Another tour used a four-wheel-drive Unimog and a river raft to get across the Fox River on to the ice, said Jewell, who is chairman of the Glacier Country Tourism Group.
The Department of Conservation was supporting concessionaires to ensure guided groups had access to the ice.
"There's still a good future there for safely getting on to the ice and for tourists to see and experience the glaciers," he said.
The West Coast glaciers were unusual because they terminated near sea level in a temperate rain forest and were only a few kilometres from a highway.
Purdie said a remotely piloted quadcopter was used recently to survey freshly exposed slopes prone to rockfall just above the Fox Glacier.
Hundreds of photographs were taken so a model could be created to look at how far rock falling from the slopes above the glacier could cascade on to the glacier surface.
"This is important knowledge which will assist the local guiding company when planning safe routes for the guided walks," she said.