Last week, the environmental community lost a beacon of wisdom and inspiration, a gentle and passionate man who dedicated his career to raising awareness of the oceans' unique ecosystems and Japan's in particular. On Friday, at the age of 74, Jack Thomson Moyer is believed to have taken his own life, leaving family, friends, colleagues, and the natural world he loved, far poorer for the loss.

A marine biologist and a dedicated environmentalist and educator, Moyer spent two-thirds of his life in Japan, sharing with young people his knowledge of marine species and his passion for the seas. Originally from Topeka, Kan., he came to Japan in 1951 as a scientist with the U.S. Air Force. In 1952 he made his first visit to Miyake Island, off the southern coast of Tokyo. He fell in love with the island and spent the next half a century there, immersing himself in studies of birds, dolphins and coral.

Then, three years ago, paradise was lost. In September 2000, Moyer and 4,000 other residents were forced to flee as massive volcanic eruptions began to bury the island in ash. A month after moving to an apartment in Tokyo, one of those provided for Miyake refugees, Moyer was asked by The Japan Times if he now intended to stay in Japan. "What's the point of going back to the United States? I am a Miyake man. The islanders are my people," he replied.

From the start, Moyer proved to be a true island man. His first visit was to check out a rocky island southeast of Miyake that was being used for target practice by the U.S. Air Force. Finding a population of rare seabirds (Japanese murrelet) breeding on the rocks, Moyer wrote to an associate of U.S. President Harry S. Truman appealing for a halt to the bombing. Truman honored the request, and Moyer stayed on, enchanted by the island's beauty. "Although I did not know it, I had embarked on a career as a marine biologist," he wrote several years ago.

Decades later, Moyer remained in awe of Japan's islands and oceans. Just two years ago, in the January 2002 Japanese edition of National Geographic, he waxed lyrical when he wrote: "No other nation in the world offers a more varied and rich marine environment. . . . In these days of endangered species and dwindling wildlife, [Japan's] rich oceans rank with the tropical rain forests of the Amazon in the irreplaceable value of their biological diversity."

Moyer was perplexed, however, by the general failure of Japanese to recognize such spectacular beauty. "I often wonder why so many Japanese ocean-lovers go to far-off Hawaii, Palau, the Maldives and elsewhere to see beautiful oceans when they have as much, plus more, in their own backyards!" he wrote in National Geographic.

But Moyer was also shocked and disturbed by the steady degradation of Japan's waters, particularly the loss of marine biodiversity; and on this page he voiced increasing disenchantment with the failure of the government to take marine-pollution problems seriously:

"Unfortunately, [the] dramatic loss of biodiversity is lost on many new divers who, not knowing what the oceans used to be, perceive what remains as beautiful, relatively diverse. . . . They will never know what it was like before . . .

"As most people do not dive, they have even less knowledge of the rapidly shrinking marine biodiversity, and one of my biggest frustrations is my inability to convince either the public or government leaders of the severity of the biodiversity problem . . .

"We owe it to our children and grandchildren to stop our selfish destruction of the planet's life forms (including our own) -- and to save what remains for future generations," he wrote in August 2002.

Moyer was especially concerned with the threat that agricultural chemicals pose to Japan's rivers and coastal waters, and he could not fathom society's passive acceptance of such a menacing legacy. "As I ponder the noyaku [chemical] problem, I ask myself again: Why must we humans insist on exploiting the environment for our own convenience, without giving a thought about the environmental wasteland we are leaving for our grandchildren?" he asked in The Japan Times in October 2002.

With return to Miyake impossible, Moyer's writing began to reflect mounting frustration. Work required that he be in Tokyo, but city life was grinding him down, and he desperately missed his family in the Philippines.

The final chapter of his Japanese autobiography, "Ikimono mina tomodachi (All Living Things Are Friends)" (Freobel Kan, 2002), concludes on a plaintive note. "I have only one immensely important, unfulfilled desire remaining in my life. I want to be able to spend the end of my life with my beloved family, Lorna, Jackie and "LL." Will I ever have the opportunity for this dream to become a reality?" he wrote.

His Japan Times articles, too, show growing impatience with the status quo. "As anyone with an iota of awareness and no partisan ax to grind must surely know by now, this planet's nature is in danger of being mostly destroyed within the next century, with catastrophic consequences for human life," he lamented last summer.

Sadly, for those left stunned and empty with loss, Moyer was one of the few dedicated souls who give us hope that, despite the status quo, this planet's unique beauty can be saved.

But, first and foremost, Jack was an islander, and the longing to return must have been overwhelming -- he had already been away from his island home far too long.