Braided Waters - Wade Graham Western Histories

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together with their geologic history, accounts for much of their physical—and in certain ways, their social—destiny. From its origin over a stationary, midplate hot spot now under the island of Hawai‘i, the Hawaiian chain extends 2,449 miles westward toward Kure Atoll, where the eroding volcanoes submerge, then carries on northward as the Emperor Seamounts, ending at Meiji Seamount, beyond which the Pacific Plate subducts into the Kuril Trench off Kamchatka. The oldest seamounts date to seventy-five million to eighty million years; the islands’ life span above water varies from eight million to fifteen million years.16 Active volcanism is limited to the zone directly over the hot spot: three volcanoes on the island of Hawai‘i—Mauna Loa, Hualalai, and Kilauea—and Haleakala volcano on Maui, have erupted historically (since 1778). Mauna Loa last erupted in 1984, while vents on Kilauea have erupted continuously since that year. The island-making process continues: Loihi, a new, actively building, submerged volcano southeast of the Big Island, is expected to surface in roughly one hundred thousand years.

      On these islands, age is fundamental to form. The Big Island of Hawai‘i, so new that its surface rocks are no more than a million years old, has no significant stream valleys with developed soils, except on its northernmost and oldest coasts, Kohala and Hamakua. Offshore, its slopes drop precipitously into deep water, and consequently, the island has no fringing coral reefs. By the same token, as islands increase in age, erosion gradually changes their character: at the other end of the main group, five-million-year-old Kaua‘i is typified by deep canyons, broad and swampy coastal valleys, and more generous fringing reefs than on the other islands.

      As age equals geomorphology in a general sense, topography is fundamental to climate at the local level, and variation is tremendous. Ten percent of the main island area is above 7,000 feet, with relatively cold temperatures; Mauna Kea volcano on Hawai‘i reaches 13,796 feet and boasts ancient glaciers and a seasonal snowcap. Precipitation varies abruptly and radically depending on local topography, with the main dynamic being orographic rain produced over windward mountains by the prevailing trade winds from the northeast and compensatory rain shadows in their lees: Mount Waialeale on Kaua‘i receives up to 486 inches of rain, more than forty feet, the highest total in the world; not far away, in its rain shadow, is a desert. The northeasterly trades are so predictable—blowing at or above twelve miles per hour 50 percent of the time in summer and 40 percent of the time in winter—that the windward/leeward (ko‘olau/kona) distinction orders climate, vegetation, and land use a priori in Hawai‘i.17 With the exception of areas too low to create orographic clouds (below about one thousand feet) and that are therefore largely arid—such as West Molokai and much or all of Lana‘i, Kaho‘olawe, and Ni‘ihau—windward areas are wet, and leeward ones are dry, irrespective of elevation. Windward coasts (with the previous exceptions) are well watered yet see some sunshine most days. With increasing elevation, windward ranges are wetter and more often cloud shrouded, clothed in deep forest dominated by ohi‘a lehua (Metrosideros collina), until the alpine zone, above eight to ten thousand feet. At higher elevations, the flanks and lees of mountains are covered in mixed mesic, or medium rainfall, forest dominated by koa (Acacia koa). Low leeward areas once grew a distinctive, variegated dry forest, though this has been very nearly wiped out since human colonization and replaced with grasslands. Precipitation gradients are commonly extreme, as much as 118 inches in a mile, though more typically 25 inches per mile.18 Nearly every main island has rain forests just around the corner, so to speak, from semiarid zones or near-deserts that see fewer than 20 inches per year. In between can be found a representative of every climate zone on Earth from subtropical to alpine, save true tropical humidity and polar cold. Mark Twain wrote in 1866 that if a person were to stand at the top of Mauna Loa, “he could see all the climes of the world at a single glance of the eye, and that glance would only pass over a distance of eight or ten miles as the bird flies.”19 Indeed, on the Big Island of Hawai‘i, one can deliberately select one’s preferred weather conditions by simply driving for five to twenty minutes.

      Even so, fully half the islands’ area is below two thousand feet, with a stable year-round temperature ideal for cultivating the oceanic crop suite: temperatures average 77 degrees Fahrenheit at sea level and vary seasonally about 5 degrees Fahrenheit at Hilo and 6.5 degrees at Honolulu. Below five thousand feet elevation, the seasonal variation does not exceed 9 degrees, and this is almost exclusively where the precontact Hawaiians lived and worked.20

      Insularity and isolation, more than any other factors, have shaped Hawai‘i’s natural history. Because of the “volcanic conveyor belt,” habitats have continuously evolved, fragmented, and disappeared as new islands have arisen, and old ones have eroded and disappeared.21 As specks of land in the mid-Pacific ocean, any animals or plants that reached Hawai‘i had to do so over vast expanses of water—limiting potential immigrants to those that could fly or ride exceptionally well. There were no reptiles, amphibians, or land mammals, save one species of bat, in Hawai‘i prior to human settlement. This lack of representation of groups common on more varied continental areas is called disharmony and extended even to types of insects and birds that presumably had better chances of colonization, so great was the difficulty of successfully establishing a population. Hawaiian flora and fauna is disproportionately made up of members of a handful of families. In fact, the prehuman Hawaiian flora of eleven hundred species can be accounted for by just 275 successful immigrants over 27.5 million years, a rate of one introduction every 100,000 years.22 A corollary of disharmony is impoverishment of diversity—that is, a biota made up of less than the full complement of species that made up the ecosystem in which the immigrant organism evolved: competitors, congeners, predators, and parasites. Successful immigrants into a depauperate environment are then free to move into and adapt to open habitat niches, a process called radiation, often rapidly speciating into a variety of new forms unprecedented in their ancestry. As an archipelago of continuously transforming high islands with radical climatic gradients over short distances, Hawai‘i presented successful colonists with a dizzying array of different habitat types, resulting in stunning biodiversity and a level of endemism unknown elsewhere in the world. Among plants, insects, spiders, moths, birds, freshwater fish, shrimp, and snails adapted to trees, land, and freshwater, evolution produced not only new species but entire genera unique to Hawai‘i. Among the forest birds is the most spectacular example, the Drepanidae, or Hawaiian honeycreepers, with forty-two historically known species exhibiting an extraordinary diversity of color, form, and lifestyle, all descended from a single ancestor.23 Had Darwin landed in Hawai‘i before the Galápagos, he might have had the evidence he needed to come out with his theories decades earlier.

      Yet in the process, it is typical of colonizing organisms to lose the extraordinary powers of dispersal that got them to the islands and shed defensive characters that no longer serve any purpose. With no herbivorous animals, Hawaiian plants generally have no thorns or toxic compounds: mints have lost their oils and raspberries, their spines. This loss of defenses would come back to have devastating consequences when Hawai‘i was suddenly “reconnected” with continental flora and fauna with the advent of Polynesians and later, Europeans and Asians.24

      Molokai had its share of unique species, including, in the historic period, the endemic birds kākāwahie, or Molokai creeper (Paroreomyza flammea); ō‘ō, or Molokai or Bishop’s ō‘ō (Moho bishopi); mamo, or black mamo (Drepanis funerea); and numerous plant species, including the lo‘ulu palms Pritchardia forbesiana and P. lowreyana and the tree hibiscus Kokia cookei.

      SETTLEMENT OF MOLOKAI

      Molokai, the fifth largest of the eight main islands, is 38 miles long and 10 miles wide at its widest point, with an area of 260 square miles and a coastline of 100 miles. It lies 25 miles southeast of O‘ahu, 8.5 miles northwest of Maui, and 9 miles north of Lana‘i—a position in the center of the archipelago and thus at the locus of four of the archipelago’s most important channels and essential sea travel routes. This location may have been memorialized in its name, as molo means “to interweave and interlace,” and kai means “sea” or “seawater.” Or the name is of unknown, ancient origin and cannot be translated—though this seems unlikely given the wealth of layered linguistic tradition around names in Hawai‘i and Polynesia, generally. (The use

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