Hawaii - Jeff Campbell [45]
As each volcanic island moves off the hot spot, it stops erupting and starts eroding. At the far northwestern end of the chain, the islands have receded below the ocean surface to become seamounts. Moving eastward from Kure Atoll, the islands get progressively taller and younger until you reach Hawai′i the Big Island, the still-growing, million-year-old child of the group. Straddling the hot spot, Hawai′i’s Kilauea is the world’s most active volcano. All Hawaiian volcanoes are shield volcanoes that erupt with effusive lava (creating gentle dome-shaped mountains), though they have an explosive side, as Kilauea reminded everyone in 2008 (Click here).
Under the sea about 20 miles east of Hawai′i, however, a new volcano is erupting – Lo′ihi. In 30,000 years or so, it will emerge from the water to become the newest island in the Hawaiian chain.
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A World Between Waves, edited by Frank Stewart, is a great essay collection covering everything from volcanoes to whales, including a fantastic account of Captain Cook’s first voyage from the perspective of his naturalists.
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Within the state of Hawaii, there are eight main islands, only seven of which are populated. West of Kaua′i, the minuscule islands and atolls of the Northwestern Hawaiian Islands (Click here) stretch for a thousand miles. In all, Hawaii constitutes only 6423 sq miles. This accounts for about 1% of the total US landmass, an area slightly larger than the state of Connecticut. On the Big Island, Ka Lae is the southernmost point in the US, a latitude equivalent to Hong Kong, Bombay and Mexico City.
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WILDLIFE
Born barren, the Hawaiian Islands were originally populated only by those plants and animals that could traverse the ocean – flying themselves, floating along the jet stream, or riding the waves. Seeds came in bird wings, insects on driftwood. Most species that landed didn’t survive. Scientists estimate that successful species were established maybe once every 35,000 to 70,000 years – and they included no amphibians, no browsing animals, no pines, no mosquitoes and only two mammals: a bat and a seal.
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SACRED HONU
Native Hawaiians revere the green sea turtle, which they call honu. Often considered a personal ′aumakua (protective deity), honu’s image frequently appears in petroglyphs (and today in tattoos). For ancient Hawaiians, sea turtles were a delicious and prized source of food, but their capture and consumption were typically governed by strict religious and traditional codes.
As with all seven types of sea turtles (four of which can be found in Hawaii), the green sea turtle is now endangered and protected by federal law. Adults can grow over 3ft long and weigh more than 300lb. Young turtles are omnivorous, but adults (unique among sea turtles) become strict vegetarians. This turns their fat green – hence their name.
Green sea turtles can be found throughout the Hawaiian Islands; they are often seen feeding in shallow lagoons, bays and estuaries. However, their main nesting sight is the French Frigate Shoals in the Northwestern Hawaiian Islands (Click here). Here, up to 700 females (90% of the population) come to lay their eggs every year.
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However, the flora and fauna that made it occupied an unusually rich, diverse land, containing nearly every ecological or life zone. In a prime example of ‘adaptive radiation,’ the 250 flowering plants that arrived evolved into 1800 native species; 20 kinds of land snails became a thousand species. Lacking predators or much competition, new species dropped defensive protections: thorns, poisons and strong odors disappeared. This process accounts for why such high percentages of native Hawaiian species are endemic, or unique to the islands, and why they fare so poorly against modern invaders.
When Polynesians arrived, they brought new animals and plants (sometimes called ‘canoe plants’). These ‘Polynesian introductions’ included pigs, chickens, rats, coconuts, bananas, taro and about two dozen other plants, not to