Palm Plight
Assaulted by myriad threats to their survival, palm species around the world face the likelihood of extinction
- By Mike Grudowski
- Smithsonian magazine, August 2002, Subscribe
(Page 2 of 5)
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.
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