Novel ecosystems, invasive species, urban wildlife, parks, and abandoned agriculture lands – these are the ingredients of nature in the 21st century, according to a concurrent session at the 2015 Breakthrough Dialogue. The task of conservation is to embrace, not reject, the dynamism of nature.

The dominant paradigm in ecology sees evolution as a process that creates perfected ecosystems where every species serves a particular function. As a result, conservationists have worked hard to prevent and sometimes eradicate newly arrived species, calling them threatening to the existing ecosystem.

Today, a new school of ecology understands nature very differently, argues environmental journalist Fred Pearce. In the new paradigm, ecosystems are not understood as stable, but constantly shifting, with species arriving, departing, and attempting to carve out a life.

Invasive species are a perfect example of this process, said Pearce, who looked at the effects of “invaders” across six continents for his recent book The New Wild.

“What I found was that invasives are not only intrinsically bad as everyone thought,” he said, “they are also a good thing; they add to biodiversity and colonize places disturbed by humans and do things native species often cannot do.”

Pearce pointed out several cases where invasives had a positive effect on the surrounding ecosystem: zebra mussels cleaned up the Great Lakes; water hyacinths consume excess nutrients in waterways across the tropics; and birds like the Japanese white-eye disperse seeds of native shurbs.

“Nature needs these colonists and go-getter species that move in and sometimes undo damage, whether its former forestland in Puerto Rico or polluted waters near industrialized areas,” he argued.

There may be no better place to understand novel ecosystems and new species interactions than on the island of Hawaii, said tropical ecologist Joseph Mascaro, who spent several years there.

Over several centuries, Hawaii’s biodiversity has more than doubled thanks in large part to the arrival of introduced and invasive species. Hawaii has more than 1,000 native plants, for example, and more than 1,000 successfully introduced species and another 10,000 cultivated species that have the potential to become naturalized.

“Hawaii would have to lose 100 percent of its native species and 20 percent of its introduced species to have net loss in plant diversity,” said Mascaro.

As a discipline, ecology too often has adhered to arbitrary baselines of the past, such as before the arrival of humans, to which they seek to return nature. “Ecologists have lost the ability to understand how nature is changing all the time, and changing in timescales that our brains are sometimes incapable of perceiving,” he said.

Environmental philosopher Mark Sagoff cautioned against ecology and conservation deploying more science to address this failing, however. In Sagoff’s view, the ecologists who theorize in laboratories how nature behaves can never carry out the work of conservation.

“The perception of nature is always personal, particular, specific. You cannot perceive nature as an abstraction such as ecosystem services,” said Sagoff. “The enemy are the theorists, the royal ‘We’ conservationists who don’t know anything about a wren or a warbler.”

Sagoff argued that the real work of conservation is carried out by the thousands of local conservation groups trying to save particular species and places, not the ecologists concerned with scientific concepts like biodiversity.

If nature is constantly evolving and there is no a priori baseline from which to work, yet there will be consequences for human interventions, panelists agreed we need better strategies for conservation in the 21st century.

Price suggested that conservation should no longer make appeals to the “intrinsic value” of nature, which she believes is the weakest argument, and instead make obvious the multitude of values – aesthetic, economic, health – that motivate local decisions to protect wild spaces.

Mascaro pointed to the work of Elena Bennett of McGill University as one model for the next generation of ecologists. Bennett’s research laboratory goes out into the community, identifies the various stakeholders with competing values and interests, and works to design regional landscapes to deliver the services they want in the most democratic and sustainable manner possible.

“That is novel ecosystem management ecologists have been clamoring for, and academics don’t have the guts to do it,” Mascaro said.

Conservation, and environmentalism more broadly, also needs to become less elitist, said Price. She pointed to the city of Los Angeles as an example of how access to green spaces has become a social justice issue.

“Much of environmental education is about taking kids out of the cities and into the distant wilderness, which I think is completely misguided,” Price said. “You need green spaces in these cities, especially in places where populations have been deprived of them for decades.”

“There’s a lot of conservation, in places like California, motivated by wealth and a lot of exclusivity,” added Sagoff.

Urban ecology is an important dimension of nature in the 21st century not just because of social justice, pointed out Pearce, but because that’s where more and more wildlife is turning up, particularly in Europe.

“You go into urban environments and there are these weird niches, chemical backwaters, and domestic gardens with foreign arrivals – that’s where nature is,” Pearce said.

Embracing such novel ecosystems can reignite the conservation movement, said Mascaro, speaking as an ecologist.

“Giving up our moral authority to rebuild some ‘pristine’ place of the past is not the same as reducing our enthusiasm for conservation or turning down the temperature on our need to protect species.”

How Should We Think About “Nature” in the 21st Century?

Jul 14, 2015