Visitors are also apparently slightly less satisfied with visiting New Zealand than they were two years ago when the survey first started. That fell from 8.3 on a 10-point scale to 8.2.
And although a greater proportion of tourists are travelling by air, overseas visitors are slightly less satisfied with international and domestic flights than they were a year ago.
Inbound Tourism Operators Council chief executive Paul Yeo said the industry was struggling to attract high-quality staff. "The fact is there are not enough good people out there."
More relaxed rules covering short-term foreign workers had eased the shortages in some areas but this had to be balanced against overseas visitors' wishes to deal with New Zealanders, he said. The survey finds the average length of stay has fallen in the past three years. In 2004 visitors stayed for around 25 days but now stayed around 20 days.
"International visitors now have less time to spend across a wider range of regions each which may be competing aggressively for their business," say study authors Angus & Associates..
The growth in influence of online media, particularly unofficial websites not published by tourism authorities, was also significant.
Canterbury scored highly. Of those surveyed, 81 per cent said they would recommend people holiday in the region and 82 per cent said they were highly satisfied with their visit - compared with the national benchmark of 72 per cent.
Tourism Minister Damien O'Connor said the fact visitors had increasingly high expectations was an important trend to monitor and prepare for.
Delivering a world-class visitor experience is one of the goals in the Tourism Strategy 2015.
For the year ended last month, 2.4 million international visitor arrived, up by 74,000 on the previous year.
The regional visitor monitor is done in partnership between the Government, Tourism New Zealand and Regional Tourism Organisations for Auckland, Rotorua, Wellington, Canterbury, Queenstown and Dunedin.
* TOP 10 EXPERIENCES
Visiting friends and family
Mountains
Lakes
Waterfalls
Maori culture/performances
Other natural attractions
Concert/theatre/arts
Geothermal attractions
Scenic drives
Rivers