VANCOUVER, British Columbia -- He recycles like mad to cut his family's garbage down to one bag a month, uses refillable fountain pens, cloth handkerchiefs and reusable chopsticks, and gets around on buses, bikes and skates.
David Suzuki is the first to concede the triviality of such individual pursuits to conserve the planet's resources.
But Mr. Suzuki, Canada's best-known advocate of environmental causes, says it is important to start somewhere to conserve a world threatened by unbridled economic growth -- and to live by one's beliefs.
"We just can't go on this way," he said in his tiny office near the University of British Columbia, where he is a professor of zoology.
"We live in a finite world. Nothing can continue to increase forever. We have to pull back and let nature recover to the best of its ability."
He is not very optimistic about persuading others to pull back to save the planet, citing a virtual disappearance of environmental issues from world attention after the 1992 United Nations Earth Summit in Rio de Janeiro, Brazil.
His daughter, Severn, who was then 12, made a moving plea there for conservation for a new generation.
Mr. Suzuki says an estimate by a friend, Harvard biologist and entomologist Edward Wilson, that more money is spent in New York City bars in two weeks than on studying biodiversity for a year makes him even more dispirited. "That shows you what our economic priorities are," said Mr. Suzuki, 58.
A quarter-century ago, he turned from a promising career in genetics to focus on the environment. He has evolved into an icon, combining environmental crusading with a successful effort popularize science.
Such Canadian Broadcasting Corp. television shows as "Suzuki on Science" and "The Nature of Things" (which has been seen on public television in the United States, as has his 1993 series, "The Secret of Life"), his more than 20 books, and weekly columns in at least 30 newspapers have given him instant recognition in Canada.
He is not without critics. Two prominent newspapers have dropped his column. The Globe and Mail in Toronto complained about his "narrow focus." The Vancouver Sun said he had become "repetitious and boring."
Even admirers have called his environmentalism "religious zealotry."
Mr. Suzuki does not take exception to that characterization. "Yes, the issues ultimately are spiritual," he said. "They have to do with what we are, what is our place, how we were meant to live and the future of our children."
In 1969, his work at the University of British Columbia exploring mutations in fruit flies earned him an award as Canada's outstanding scientist under age 40. But the study of genetics and its link to bitter childhood memories drove him out of that field.
In 1942, during World War II, his Japanese-Canadian family was stripped of assets, split up and sent to internment camps.
A love of nature was stirred by his father, Kaoru Carr Suzuki, who took him camping and fishing, teaching him how to bait a fishhook with grasshoppers and to stand still when a bear crossed the path.
"It became clear by the late 1960s that the major issue confronting us was planetary ecological change," he said. "The human numbers were increasing at such a rate, the consumptive demand of our species was so great that the Earth was already having trouble responding."
He hopes to build environmental consciousness at the community level, and started a foundation to promote such concepts as the "ecocity," helping urban dwellers to shrink their ecological footprint, for example, by reducing the amount of garbage they create.
One Vancouver-based organization sends out women who hold the equivalent of environmental Tupperware parties to promote recycling and changes in buying habits.
Mr. Suzuki contends that women are the most committed environmentalists.
Why? he was asked.
"Women think about children," he replied. "And they think about the future."