Successful ecological restoration projects in Hawai‘i show the potential of repairing damaged ecosystems
The planet’s most endangered forest is not in Brazil or Borneo – it's actually in the good old USA, literally and figuratively clinging to a steep slope in a remote section of the Hawaiian Island of Kaua’i.
When I first visited this mysterious forest in Kaua’i shortly after I began working at the National Tropical Botanical Garden in 1996, I was struck by the fact that so many of its plants were federally endangered species found only on this island. I was also shocked that essentially nothing was being done to protect this priceless ecosystem. Today, I’m happy to report, that’s changing. Biologists and community groups in Hawai‘i are busy trying to restore degraded ecosystems.
The Hawaiian archipelago’s unrivaled level of biological endangerment is largely a product of its extreme geographic isolation. Before humans arrived about 1,000 years ago, very few species were able to colonize these islands. The ones that did evolved into some of the world’s most fascinating and unusual creatures. It’s a common misconception that most or all of these colonists had spectacular subsequent evolution, but in fact only a few did; they were just as susceptible to ecosystem changes. The arrival of humans led to a suite of disturbances – habitat loss and degradation, noxious alien species, exotic diseases – that resulted in ecological catastrophe.
Consequently, three quarters of the United States’ bird and plant extinctions have occurred in Hawai‘i, and one third of the country’s threatened and endangered birds and plants reside within the state. Of the 59 species listed as “endangered” by the Obama administration in the past two years, 48 have been Hawaiian plants and birds. These islands now contain more endangered species per square mile than anyplace else in the world.
Yet all is not lost: There are still 12,000 extant species found only in Hawai‘i, and new species are discovered every year. Moreover, numerous groups are demonstrating that at least some of this biological paradise can be saved. As different as these groups often are, they are united by their desire to proactively manage Earth, both to preserve its biological diversity and to create more meaningful and sustainable relationships between people and nature. In other words, they are committed, not just to preserving natural areas, but to restoring them to something closer to their pre-human contact state.
The Hakalau Forest National Wildlife Refuge on the island of Hawai‘i is a great example of the power and promise of ecological restoration. Twenty years ago much of the higher elevation portions of the refuge were treeless pastures dominated by invasive alien species. Lower elevations of the refuge had large sections that were relatively pristine and home to native birds. Recent bird surveyors at Hakalau (Hawaiian for “place of many perches”) spotted all five of the common native forest birds and four endangered forest birds within the once treeless sections of the refuge.
When this refuge was established in 1989, 200 years’ worth of severe degradation had converted much of what had been magnificent montane rain forest into an ecological wasteland. Undaunted, Hakalau’s staff boldly set out to restore that wasteland and reconnect it to the relatively pristine surviving rain forests lower in altitude. “We wanted to create higher-elevation, high quality habitat for the native birds as quickly as possible,” Jack Jeffrey, the refuge biologist from 1990 to 2008, told me. “We knew they wouldn’t leave the existing intact forest and fly out over those open pastures.” The restoration was forward-looking and took into account what species would need in terms of a resilient habitat in the era of climate change. If global warming results in non-native mosquitoes surviving at higher elevations, the birds will also need to keep moving upward to escape avian malaria.
To accomplish this goal, the refuge staff and an ever-growing band of volunteers planted long corridors of native, fast-growing koa trees up and down the pastures. After seeing little unassisted native plant establishment within these corridors, they planted a diverse assortment of other native species beneath the protective koa canopies. Today these corridors stretch across the entire refuge and contain more than half a million native trees and thousands of endangered plants.
“In the beginning,” Jeffrey recalled, “I was very pessimistic because I was going to areas where the birds had been in the not-too-distant past, and now they were effectively gone. I even saw or heard the last individuals of some bird species that are now extinct. But when I got into restoration, I started to realize that we can do things that make a big difference. The success we’re having at Hakalau is very encouraging, and of course the best part is that the birds are coming back.”
Jeffrey and his colleagues stress that one of the keys to their success has been their volunteer program. In addition to the brute-force labor, volunteers generate a tremendous amount of public education and outreach, which in turn provides critical support for the restoration program as a whole. “Sometimes I’m just amazed by how strong human spirits are,” Baron Horiuchi, Hakalau’s horticulturalist and 2012 recipient of the US Fish and Wildlife Service’s Rachel Carson Award, said. “Our volunteers really want to give – you can just feel how hard they’re working. And we become so close working together.”
Leaders of the most effective restoration programs across the Hawaiian Islands all emphasize the importance of meaningfully involving volunteers and the public in general. Arthur Medeiros, a research biologist with the US Geological Survey, encapsulated this importance when he recounted the origin of his now phenomenally successful volunteer program on Maui: “One day a co-worker looked over at the heavily degraded forest we were trying to restore and said, ‘Wow…what if this works?’ I thought about that for a minute, then said, ‘What if it works and no one cares?’ So I started recruiting volunteers.”
Medeiros further engaged his local community through activities such as mentoring kids, working with the local landowners (the Erdman family of ‘Ulupalakua Ranch), forming inter-agency partnerships, and reaching out to the islands’ Indigenous people. He has also begun exploring ways to harvest materials from restored areas in a sustainable manner. “Sure,” he told me, “I want to have preserves where trees rot and nothing is taken. But I’d also like to have other places where we use the forest. You know, the ocean was the Hawaiians’ refrigerator, but these forests were their toolboxes and medicine chests.”
One of the most important take-home lessons from Hawai‘i is that restoring the human community’s connection to the land is at least as important as restoring the natural community itself. Another lesson is that even seemingly hopeless ecosystems may not be hopeless; if enough people care and get involved, we can probably save much of Hawaii’s remaining native biodiversity. If we can do it in Hawai‘i, we can do it virtually anywhere, because few if any other places are as severely degraded (though some are catching up fast).
On the other hand, if we Americans fail to preserve and restore our only tropical species and ecosystems, can we continue to lecture the Brazils and Borneos of the world about the importance of saving theirs?