"He absolutely loved the outdoors, and his kids ... it's very unfortunate."
A police spokeswoman said Dennison was reported missing about 11pm on Saturday by Kathy Dennison.
Family and friends searched the property and found Dennison's body with the wreckage of the vehicle about 2am, when emergency services were called to the scene.
"Donald had been a hunter all his life — he just loved being out in the hills," Kathy Dennison said.
He had previously worked as a contract fencer, a shearer, and a butcher at the Pukeuri freezing works near Oamaru.
"Working with livestock and farming was something he loved."