"He was an outstanding leader and a wonderful person. We are absolutely devastated by this news and we are in close contact with Graham's family at this incredibly difficult time."
Before joining Great South, Budd worked with Destination Queenstown for more than 12 years.
Southland Mayoral Forum chairman and Gore Mayor Tracy Hicks said everyone's thoughts were with Budd's family and all the staff of Great South.
"We are all shocked at the loss of Graham and it will take some time to come to terms with his death," Hicks said.
"Graham has contributed a huge amount over the relatively short time he was at Great South and he will be sadly missed."
Great South joint stakeholders committee chairman and Southland District Mayor Gary Tong said the news "is just awful and we will support Graham's family and his work team as much as possible."
"Graham was so passionate about doing the best by Southland and he and his team have worked so hard over the past two challenging years to support and help our businesses and people across the province.
"His death leaves a large hole for us all, both professionally and personally."