Terry is an ecologist, who has conducted fauna surveys for mammals, birds, reptiles and frogs in Australia and Papua New Guinea. He has worked as a rainforest ecologist and was involved in tertiary level education in Bornean rainforest on behalf of an Australian university. Terry made his first overseas trip in 1977, to Papau new Guinea, and continues to explore remote locations. He has led numerous and varied wildlife tours to Malaysia and PNG, twice had lengthy stints as a guide based at a lodge in Amazonian Brazil, and pursued wildlife in Costa Rica, Ecuador, Kenya, China, Taiwan, Sri Lanka, India, USA, New Caledonia and Morocco. In 2018 Terry took his first trip to Japan, visiting Hokkaido primarily to see Steller's sea eagle.