High Tide in Tucson_ Essays From Now or Never - Barbara Kingsolver [81]
We walked and slid down miles of gravelly slope toward the crater floor, where the earth had repeatedly disgorged its contents. Black sworls of bubbling lava had once flowed around red cinder cones, then cooled to a tortured standstill. I stood still myself, allowing my eye a minute to take in the lunatic landscape. In the absence of any human construction or familiar vegetation like, say, trees, it was impossible to judge distances. An irregular dot on the trail ahead might be a person or a house-sized boulder. Down below, sections of the trail were sketched across the valley, crossing dark lava flows and green fields, disappearing into a velvet fog that hid the crater’s eastern half.
The strange topography of Haleakala Crater makes its own weather. Some areas are parched as the Sahara, while others harbor fern forests under a permanent veil of cloud. Any part of the high-altitude crater can scorch in searing sun, or be lashed by freezing rain, or both, on just about any day of the year. Altogether it is one of the most difficult landscapes ever to host natural life. It is also one of the few places in Hawaii that looks as it did two hundred years ago—or for that matter, two thousand. Haleakala is a tiny, threatened ark.
To learn about the natural history of Hawaii is to understand a story of unceasing invasion. These islands, when they first lifted their heads out of the waves a million years ago, were naked, defiant rock—the most isolated archipelago in the world. Life, when it landed here, arrived only through powerful stamina or spectacular accident: a fern’s spore drifting on the trade wind, a seed in the craw of a bird, the bird itself. If it survived, that was an accident all the more spectacular. Natural selection led these survivors to become new species unique in the world: the silversword, for example, a plant that lives in lava beds and dies in a giant flowery starburst; or the nēnē, a crater-dwelling goose that has lost the need for webbed feet because it shuns the sea, foraging instead in foggy meadows, grown languid and tame in the absence of predators. Over the course of a million years, hundreds of creatures like these evolved from the few stray immigrants. Now they are endemic species, living nowhere on earth but here. For many quiet eons they thrived in their sequestered home.
Then humans arrived, also through stamina and spectacular accident. The Polynesians came first, bringing along some thirty plants and animals they considered indispensable, including bananas, taro, sugar cane, pigs, dogs, chickens. And also a few stowaways: rats, snails, and lizards. All of these went forth and multiplied throughout the islands. Each subsequent wave of human immigration brought fresh invasions. Sugar cane and pineapples filled the valleys, crowding out native herbs. Logging operations decimated the endemic rain forests. Pigs, goats, and cattle uprooted and ate whatever was left. Without a native carnivore to stop them, rats flourished like the Pied Piper’s dream. Mongooses were imported in a harebrained plan to control them, but the mongoose forages by day and the rat by night, so these creatures rarely encounter one another. Both, though, are happy to feast on the eggs of native birds.
More species have now become extinct in Hawaii than in all of North America. At least two hundred of the islands’ endemic plant species are gone from the earth for good, and eight hundred more are endangered. Of the original cornucopia of native birds, many were never classified, including fifty species that were all flightless like the dodo—and now, like the dodo, all gone. A total of only thirty endemic bird species still survive.
It’s quite possible now to visit the Hawaiian Islands without ever laying eyes on a single animal or plant that is actually Hawaiian—from the Plumeria lei at the airport (this beloved flower is a Southeast Asian import) to the farewell bouquet of ginger (also Asian). African flame trees, Brazilian jacarandas, mangos and banyans from India, coffee from Africa, macadamia nuts from Australia—these