Thursday, October 18, 2007
Birds Going Extinct
Bird populations are plummeting while we speak. Global warming and habitat destruction are main causes for their extinction. Here is a list from Worldwatch Institute of why bird populations are declining:
Habitat loss: Deforestation rates from 50,000 to 170,000 square kilometers a year pose the single greatest overall threat, jeopardizing 85 percent of the world’s most threatened bird species. While forest re-growth initiatives offset the net losses, for many native animals and plants, simplified plantation mono cultures are no substitute for more complex natural forests. Roads and power lines frequently cut through forests, fragmenting them, increasing the chance of fatal collisions, and providing pathways for predators, competitors, and exotic plants. Intensive hunting often follows when roads cut into forests.
Alien attacks: A rise in global trade and travel over the past century has led to an acceleration in the introduction of exotic (non-native) species. Exotic species—including snakes, rats, cats, plants, and insects—now menace a quarter of globally threatened bird species.
Chemical threats: Large oil spills threaten many seabird populations, but small, less-publicized daily tankers also kill birds. Terrestrial habitats also face threats from oil and natural gas exploration, and transport via pipelines. Worldwide, pesticides kill millions of birds on water and on land.
Hunting, Capture, and Fishing: Illegal hunting and poorly regulated laws lead to the killing of millions of birds around the world. Birds can be loved to death too: Almost a third of the world’s parrot species are threatened with extinction because of the pet trade, and long-term habitat loss. Long line fishing also claims hundreds of thousands of seabirds—23 species now face extinction—when they are inadvertently hooked on baited lines and drowned.
Climate change: Recent evidence of earlier bird migration and nesting in some species seems to indicate early effects of global warming. Scientists fear that in coming years climate change will alter vital bird habitats, from tundra to subtropical coastlines, even pushing some localized species towards extinction.