After more than 30 years, Gus Mills is returning to the home of his heart in the sands of the Kalahari, to once again conduct groundbreaking research into the carnivores that survive in the arid land.
For the last 21 years, Gus has worked in the Kruger National Park (KNP) finding out previously unknown facts about wild dogs, cheetahs, lions, hyenas and other carnivores, but his career began in the Kalahari Gemsbok National Park studying brown hyenas.
For the last five years of his tenure with South African National Parks, he is welcoming the return to fieldwork after several years of increasing paperwork and policy formation.
Gus plans to study cheetah in what is now the Kgalagadi Transfrontier Park, looking at how the speedy predators are influenced by the migrations of their prey animals, such as springbok, which lead a very nomadic life in the Kalahari.
Early next year he will travel to the desert to set up pilot studies that will guide the fieldwork that will begin when he and his wife Margie move permanently into their new home. The cheetah study will be long-term, as Gus says that one of the most important things that he has learnt in his decades in Kruger is that a true picture of the dynamics of wild populations and all their fluctuations are only revealed by lengthy observation. Prior to his career as a zoologist, Gus says that he had "a poor academic record", and three years of studying psychology "taught me what I don't want to do".
He now encourages children "to do what your heart says". Initially discouraged from studying the sciences, when he finally started studying zoology he was "highly motivated", and is now an international authority on carnivores, with over 100 publications bearing his name, including an authoritative scientific text on the behaviour of brown and spotted hyenas.
His position with Sanparks is a joint position with the Endangered Wildlife Trust (EWT), where he is the head of the carnivore conservation group. He also sits on several IUCN (World Conservation Union) specialist groups, including the reintroduction, conservation breeding, canid, cat and hyena specialist groups.
His expertise has led him to consult on policies to protect predators such as the Siberian tiger, the Amur leopard and the snow leopard, as well as many southern African carnivores. Gus says that carnivore conservation issues are similar throughout the world.
"Large carnivores need large protected areas and on the borders conflict always arises with people. People [around the world] have the same [negative] attitude to predators - from peasant farmers to commercial farmers."
Aside from his abiding fascination with hyenas and their complex social interactions, which are "on a par with primates", Gus has a soft spot for wild dogs. He initiated the photographic censuses that revealed wild dog numbers in Kruger with the help of the public, as well as the cheetah censuses carried out in the same manner.
At the beginning of his career, he did not have a particular interest in carnivores, but the opportunity to study hyenas in the Kalahari got him hooked. He says that anyone would have been hooked if they had had "the privilege of seeing what I've seen and what I've done".
Being one of the longest serving members of staff in Kruger, Gus has seen many changes in Sanparks over the years, not only from an ecological point of view but also sociological and political changes. He is very optimistic about the future, and says Sanparks has changed from "a rigid, authoritative, racist organisation into something a lot better.
By and large, transformation has taken place. It has been very interesting, and a wonderful thing." He adds that things are "on the right track". Gus has concerns for the future of conservation in the face of a rapidly growing human population, and believes that "too many people in the world" pose the largest threat to the earth's natural resources.
However, with his return to the Kalahari and its vast tracts of unspoilt wilderness, this human threat may become less of a pressing worry as Gus follows cheetah tracks through the sand to reveal the lifestyles of this particularly poorly understood carnivore population.