Endangered Species Handbook

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Forests' Retreat: Page 6

     The Rainforest Action Network has documented that 140,000 mahogany trees are being logged annually, with each tree worth about $1,500 wholesale in the United States, where most are marketed (Line 1996).  RAN states that most of the mahogany trees in trade have been illegally logged from parks, conservation areas or other protected lands, causing ecological damage on a large scale. 
     Mahogany takes 40 years to reach harvestable size, and the majority of this wood that is traded internationally comes from wild harvested trees.  Many tropical species have reached commercial extinction, and Honduran Mahogany, which grows to 130 feet with a massive canopy, is the major target of the logging industry in Central America.  By having a market for mahogany, especially a lucrative one, loggers seek out these trees, even in protected national parks.  Once in commerce, distinguishing legal from illegal becomes impossible.
     Trees that are commercially valuable are often the very ones most important to wildlife for food sources or shelter.  The largest and oldest trees produce the greatest profits and are the first to be cut.  These trees provide nest holes for owls, toucans, hornbills, parrots, tiny monkeys, lorises and galagos, rare lemurs, and countless other wildlife species.  Many species of wildlife use tree holes for shelter year-round.  Although some birds, such as woodpeckers, can excavate nest holes, the majority of animals who shelter and nest in tree holes depend on natural cavities.  These holes form when tree limbs fall off or from rotting within tree trunks. Research on wild macaws has determined that a lack of trees with nest holes plays a major role in limiting their populations.  Macaws nest only in large cavities very high, usually 100 feet or more, in tall tropical trees.  Only the oldest and largest trees have tree holes for the more sizeable animals, such as hornbills, macaws and families of small primates who den together.   
     The Harpy Eagle (Harpia harpyja), the world's largest eagle, is endangered in its neotropical rainforests.  Its range once extended unbroken from southern Mexico through the Amazon but today it is rare or absent throughout the remaining forests.  A major factor in its decline is logging of the tall, old trees it requires for nesting.  These eagles need a high vantage point overlooking the treetops to spot prey and to prevent predation on their nests.  Harpy Eagle chicks have a long period of fledging, and prior to their independence, they must strengthen their leg and wing muscles.  Eagle parents always make their massive nests near the top of giant trees with wide branches near the nest where the chicks can exercise by running across the branches, flapping their wings.  As the strongest avian predators in these forests, they must be able to kill animals as large as sloths and carry them off in their talons.  Loggers spot these giant trees rising over the forest canopy and cut them for the enormous amount of wood they contain.  In much of Central America, selective logging and clearcutting have destroyed many of the former haunts of this magnificent bird.
     Dead trees still standing are also prime wildlife nests and shelters, but because they are considered fire hazards, they are cut routinely.  Hollow limbs and fallen logs are used by many types of animals for shelter or nesting, and these are usually trimmed off by loggers.  Rotting tree trunks and cavities in both standing and fallen trees support entire communities of insects and invertebrates, upon which many vertebrates depend for food, and which contribute to the forest's health.   
     Modern loggers use mechanized tools and machines to clearcut forests.  Chainsaws can cut through the massive trunk of a thousand-year-old tree in minutes.  For smaller trees, saws mounted on trucks slice their trunks like matchsticks, and machines lift the trunks onto logging trucks for transport, trimming off side limbs in the process.  Every tree in a forest, ancient or young, commercially valuable or cut only to be discarded, is logged.  Forests covering 1,000 square kilometers have been completely denuded in a single clearcut.  Huge processing trucks sweep through the forests, creating deep ruts in the forest floor.  Roads are bulldozed for this logging, opening up forests, causing erosion to soils and flattening fragile plants.  Baby birds, squirrels, bats and tiny primates in tree holes are killed as their homes are sent crashing to the ground and dragged along the forest floor.

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