Palm Plight
Assaulted by myriad threats to their survival, palm species around the world face the likelihood of extinction
On a drizzly morning in paradise, ken wood and i are padding along the rim of the KalalauValley, some 4,000 feet above the ocean on Kauai’s Na Pali coast. The scenery is glorious, but something is missing. This is Hawaii, yet there’s not a palm tree in sight and palm trees are what Wood is all about. A field botanist originally from New York with a laid-back manner and filaments of gray in his close-cropped beard, Wood, 47, works for the National Tropical Botanical Garden (NTBG), on Kauai. He spends a lot of time looking for rare palms. When he finds one, he climbs it (if it’s big), snips off a frond, plucks a few seeds and shinnies back down. Today he’s looking for a fan palm of the genus Pritchardia, a group that encompasses Hawaii’s only native palms.
There are 27 species of Pritchardia, 23 of which are found in Hawaii. Eight are officially classified as endangered, but Wood is convinced others as well face the threat of extinction. Not long ago, he took a census on East Maui of one of them, P. arecina. “There are only 500 left,” he tells me, “and there is no regeneration. When there’s no regeneration, you don’t need statistics to show that the species will die off.”
The notion that Hawaii is losing its palms may sound faintly ridiculous to anyone who’s visited the island chain. Coconut palms grow so abundantly you’d think resorts would have to supply tourists with hard hats along with the customary leis. But coconuts, like taro, breadfruit and a host of other Hawaiian denizens, didn’t originate here. They arrived with the Polynesian voyagers who settled on the islands some 1,600 years ago. For millennia before that, the fan palms Wood now combs the backcountry in search of dominated the landscape.
Hawaii is by no means the only place where palms are in a pickle. Of the world’s nearly 3,000 species, about 220 are “highly threatened with extinction,” according to the International Union for Conservation of Nature and Natural Resources, and many others are headed in the same direction. Some, like the one named Hyophorbe amaricaulis, have already reached their end. This species is down to a single tree, tall and sparsely crowned, living out its days in a botanical garden in Curepipe on the island of Mauritius. It fruits regularly but the seeds it produces are not viable, and clones made from this plant have not been able to survive outside a laboratory environment. Someday the last living H. amaricaulis on earth will go the way of another, better known native of Mauritius: the dodo.
As is the case with endangered plants and animals in general, a disproportionate number of endangered palm species are found on islands. Madagascar, the world’s fourth-largest island (about the size of Texas), is an object lesson in the problems that face palms across the tropics. In the past century, the human population there has quadrupled to 12 million and most of the previously undisturbed land has been converted to agriculture. Consequently, nearly half of Madagascar’s 176 palm species are endangered or presumed extinct, with unknown ramifications for the island’s birds and other wildlife. (For more on Madagascar, see Around the Mall, p. 39.)
If they didn’t constitute such a varied family of plants, palms might be in even worse shape. They grow in African streams and 9,000 feet high in the Andes. They’re found in sweltering mangrove swamps in Southeast Asia and in blizzard-lashed highlands in the Himalayas. Some top out at six inches, and others tower upwards of 200 feet; rattan palms (which grow as vines) can exceed 600 feet in length. The palm family boasts the plant kingdom’s largest seed, the double coconut of the Seychelles, which weighs more than 40 pounds. African raffia palms have the longest leaves on earth, some reaching 75 feet or more. “Because palms are so diverse, they’ve risen to dominance in many ecosystems,” says Scott Zona, a palm botanist at FairchildTropicalGarden in Coral Gables, Florida. “They’re characteristic of savanna forests, rain forests, gallery forests along rivers, and mangroves. There’s opportunity in diversity.”
Like many plants, palms get help in seed dispersal from the creatures who depend on them for nutrition. The date palm tree of the desert Middle East produces 500 pounds of seeds, or dates, each year. Dates are sweet, so sugar-loving “dispersers” from parakeets to pachyderms consume their flesh and then drop, regurgitate or otherwise deposit pits wherever they go. In similar fashion, various other palm seeds or fruits feed electric eels in the Amazon, vultures in South Africa, orangutans in Indonesia, coyotes in Mexico and elephants in India.
Coconut palms, however, rely on seawater for dispersal. A coconut palm can grow 130 feet tall, so its seed comes packaged to survive its eventual crash to earth with a husk made of cushiony fibers called coir. The nut may grow where it lands, or if it plunks into the ocean and gets swept away, it may take root 3,000 miles or more from the mother tree. Coconuts from the West Indies have been cast up on the shores of England and northern Europe.
Palms put food on the table for people directly and indirectly. Almost half a million people in the South Pacific rely entirely for their livelihood on coconut palms grown commercially on Fiji and other Pacific islands, like Samoa. Coconut oil and coconut milk are important food sources in this part of the world. There are very few parts of a palm that somebody, somewhere, hasn’t found useful. If a latter-day Robinson Crusoe got marooned on an island blessed with a serendipitous mix of palm species, he could nibble on dates while toasting coconut meat over coconutcharcoal embers; nestle into a rattan-palm recliner in his palm-post bungalow under a palm-thatch roof while writing a screenplay with palm dye on palm paper; buff his palm-plank surfboard with carnauba palm wax; stroll in the rain with a palm cane and a palm-frond umbrella; take a cue from Venezuela’s Warao Indians by using a palm leaf as a canoe sail; and end the day watching a palm-fringed sunset over a palm-wine nightcap.
“Palms are the trees of life,” says Mike Maunder, NTBG’s conservation director. “They’re absolutely fundamental to many tropical ecologies and economies. Take away palms, and tropical ecosystems can be profoundly damaged.”
According to Melany Chapin, who oversees NTBG’s collections of live plants, the main problem with Hawaii’s native palms is that “they don’t have any defense mechanisms, because they never had any native predators to contend with.” For millions of years, Hawaii’s pristine lands existed in splendid isolation. Then the Polynesians introduced rats and lizards along with their crop plants. Captain James Cook and other explorers left behind pigs, sheep, goats and cattle. Mongooses, imported from Jamaica in the 1880s to prey on rats in sugarcane fields, developed a taste for native birds.
Today, just about any time a Pritchardia tries to reproduce, Hawaii’s biological invaders go to work. Rats devour most seeds before they can germinate. Goats munch any seedlings that manage to sprout. Pigs rut up the ground, damaging fragile root systems and causing erosion in steep terrain. Vickie Caraway, a botanist in Hawaii’s Division of Forestry and Wildlife, says that introduced weeds are a big problem too. They form thick mats over the soil in many areas, preventing the palm seeds from germinating.
Habitat destruction compounds the problems. Over the centuries, much of Hawaii has been burned, bulldozed and built up with cane and pineapple fields, towns, condominiums, hotels, marinas and golf courses. The lowland dry forest, where native palms once dominated, has taken the hardest hit; more than 96 percent of it is gone.
Unethical plant collectors make things worse still. The only four P.viscosa palms known to exist in the wild grow along the Powerline Trail on the eastern side of Kauai. Not long ago, NTBG botanists were thrilled to discover a fifth, a seedling that had sprung up alongside the others. When the scientists returned to the site, the seedling was gone, with a gaping hole and telltale shovel marks in its place.
As daunting as these combined threats are, hope remains. On the north shore of Kauai, NTBG is restoring Pritchardia to the wild in a 1,000-acre preserve. But most of the Pritchardia seeds Wood and his fellow scientists bring back from their expeditions get planted in the garden’s 286-acre grounds on Kauai’s south shore. There and in other protected tracts, the staff is cultivating a kind of botanical menagerie of rare palms, in hopes of preserving as much genetic diversity as possible. These plants provide a significant hedge against the possibility of extinction. Those four P. viscosa beside the Powerline Trail, for instance, now have 16 cousins growing in captivity.
Several groups are trying to save Hawaii’s palms by protecting their habitat. About two million acres of native forest and scrubland remain intact, according to the Nature Conservancy, and a quarter of them are managed by federal or state agencies, or private groups. Both national parks in Hawaii have fenced off large areas and eradicated pigs and goats. On Maui, Oahu and Molokai, a number of land partnerships have been formed in recent years, bringing together all manner of public and private landowners in cooperative efforts to thin out invasive species and protect native ones.
Meanwhile, Ken Wood and other scientists are doing what they can to preserve palms in the wild. As Wood and I trudge cautiously downhill, scanning the landscape for Pritchardia’s stiff, fan-shaped fronds, we surprise a pair of feral goats, munching at a bank of ferns. They skip down a 70-degree wash. “Bane of the terrain,” Wood mutters.
We’re probing below the rim of HonopuValley now. It’s noon, and the mist has yielded to blazing sun. Suddenly Wood exclaims: “Whoa! There’s a Pritchardia.”
Sure enough, 50 yards upslope from us, a solitary green fan peeks out from some twisted ohia branches. It’s a P. minor, one of perhaps 500 remaining. The species can grow 30 feet tall, but this young specimen is only a sixfooter. Wood cuts off a frond with his knife, folds it along its accordion pleats, wraps it with pink and black tape, and thrusts it and a handful of seeds into a plastic sandwich bag. He jots down notes with a stubby pencil: number of fronds, diameter of stem, other nearby species, elevation 3,190 feet, 300 degrees northwest. (All of that information will be stored in an NTBG database used for mapping palm distributions and abundance.) Then we head home—mission accomplished, for today, but the battle goes on.
What’s at stake can’t be measured in strictly biological terms. If palm trees should vanish from the earth, something more than genetic diversity and habitats will have been lost forever. An essential aspect of our tropical fantasies will disappear as well. Without palm trees, paradise will never be the same.