SPECIES HANG IN BALANCE SCIENTISTS LOOK AT EXTINCTION.

Byline: Beth Barrett Staff Writer

California is among 25 ecosystems worldwide where intensive work needs to be done to preserve animal and plant species to avoid environmental catastrophe, some of the world's top scientists said during a seminar in Pasadena last week.

``This is not Jurassic Park,'' Columbia University professor Stuart Pimm said. ``Many people now are understanding the planet is facing an extraordinary period of rapid change and species extinction, and extinction is completely irreversible.''

``Defying Nature's End: A Practical Agenda for Saving Life on the Planet'' was the theme of the conference, sponsored by nonprofit, Washington D.C.-based Conservation International, at the California Institute of Technology. Marquee scientists Edward O. Wilson, a Harvard professor, and Intel Corp. co-founder Gordon E. Moore were among those warning that urban areas such as Los Angeles are at higher risk of biodepletion, even as conservancy and government groups have been buying up open space around the city.

``In major urban areas, you begin to find a paucity of life,'' Pimm said. ``That's when you find rats, sparrows and cockroaches beginning to dominate in a biology-poor world.''

The four-day seminar ended on positive note, with the scientists expressing confidence in people's abilities to choose their destiny.

``We're programmed to do whatever we need to do to survive,'' said Russ Mittermeier, president of Conservation International. ``Sometimes we use the same techniques that worked when there were just a few of us, and those can have extreme effects. But we're also conscious of the impacts. We have more focus as to what we need to do.''

< Rare ecosystem

The scientists, most specializing in the burgeoning biodiversity field, said California plays an important role in the world's ecosurvival since so much land already has been gobbled up by logging, agriculture and urban or suburban development.

Only one of five Mediterranean-type ecosystems worldwide, the California Floristic Province with its 2,125 native plants has lost nearly 75 percent of its pristine habitats, according to published studies.

The province - which includes most of California, parts of northwestern Baja California and southwestern Oregon, is the only hot spot identified largely within the borders of the United States - nudging onto a list otherwise dominated by Third World, tropical ecosystems.

``The bottom line with California is for us to realize that not all our hot spots are in developing countries, that there are some in our own back yard,'' Mittermeier said.

Globally, intact ecosystems within the world's 25 hot spots are collectively equivalent to a region just slightly larger than Alaska, or 1.4 percent of the Earth's surface. They reflect about 60 percent of the planet's biodiversity, conference scientists estimated.

< California issues subtle

While slash-and-burn farming has ravaged huge tracts of land in many of the hot spots identified in the tropics, California's government, foundations and nonprofit organizations have done a reasonably good job of managing the state's open spaces and of protecting the teeming life found in its vernal pools, riparian forests and coastal sage scrub, the scientists said.

When alarms are raised about hot spots, California, New Zealand and southwest Australia may receive less attention than parts of the globe facing slash-and-burn tactics, they said.

But with more and larger houses, more paving and bigger malls and commercial outlets, the human imprint on places like Los Angeles grows, said Peter Seligmann, chairman and CEO of Conservation International.

``The imprint from each of us in Southern California and from around the country is very large,'' Seligmann said.

< Price of beauty

Robert Costanza, University of Maryland zoologist, is pioneering a field of study on how economics affect hot spots - especially how much people will pay to live in these places.

Costanza applies hedonics - psychology dealing with pleasant and unpleasant feelings - and assigns value to the pleasure people find in places with great views of sweeping beaches, majestic mountains and other natural beauty. Worldwide, he said about $1 trillion has been spent on natural aesthetics.

It is partly this economic valuation of environmental beauty that encourages biodiversity scientists to believe that people are not so deeply encoded with greed, consumerism and domination that they will forsake the treasures of nature.

``Yes, people are greedy,'' said Pimm, the Columbia professor, mentioning the recent example of how island ``Survivor'' contestants battled each other to win $1 million in the smash-hit TV show. ``But the overarching principle is that they generally want to do the right thing.''

Signs of changing attitudes are evident in legislation, philanthropic giving and personal habits, such as buying shade-grown coffee to discourage much of the clear-cutting otherwise done in third world countries.

Scientists at the conference said nothing short of half the world's 27,000 species of animals with spines, excluding fish, and 300,000 species of plants could be at stake.

``There are important ethical and religious concerns here,'' Pimm said. ``If you asked most people, do you want to destroy 50 percent of God's creation, they'd say, no, of course not.''