Bachelor cum laude, Amherst (Massachusetts) College, 1964. Doctor of Philosophy, Oxford (England) University, 1968.
Elephant ecologist, Serengeti Research Institute, Seronera, Tanzania, 1968-1972;
lecturer zoology, U. Nairobi, 1972-1975;
senior staff ecologist wildlife management project, United Nations Development Programme/Food and Agriculture Organization (of the United Nations)/Kenyo, Nairobi, 1975-1976;
director, Ecosystems Ltd./English as Second Language Computers Ltd., Nairobi, 1977-1979;
senior science affairs officer Global Environment Monitoring Sys., United Nations Environment Programme, Nairobi, 1979-1984;
director Global Resource Information Database, United Nations Environment Programme, Nairobi, 1984-1993;
assistant executive director and director environmental assessment program, United Nations Environment Programme, Nairobi, 1993-1996;
self-employed environmental consultant, Nairobi, since 1996. Consultant Rockefeller Foundation, New York City, 1997.
Board directors Global Resource Information Database, Arendal, Norway, 1995-1997.
Founding member Committee for Human Ecology in Kenya - Chek-Kenya, Nairobi. Member East African Wildlife Society (member council 1976-1990), Fauna Preservation Society, Limuru Community College, Muthaiga Country Club, Aero Club of East Africa.
Married Christiane Grieshaber, October 14, 1965 (divorced 1984). Children: Christian Anselm, Katrineka Nairobi, Andreas Lengai. Married Cristina Boelcke, August 23, 1992.