MISSING SONG:
Mass migrations, such as the annual flight of the cerulean warbler pictured here, are dwindling all over the world.Wikimedia Commons"Pick the right night and you will hear them. A September night, perhaps, when a northwest wind has swept the clouds from the sky and the stars are out in full force. As midnight approaches, find a quiet spot away from the rumbles and groans of urban life and listen carefully. Soon you will hear soft chirps and whistles drifting down from the sky. These are the calls of migrating songbirds. A thousand feet above you, extending for hundreds of miles in all directions, is a vast highway of little birds—millions of thrushes, warblers, flycatchers, tanagers, vireos and sparrows—heading south."
But maybe not for much longer—thanks to ongoing habitat destruction, the creation of obstacles such as fences or dams, overusing natural resources, and climate change.
So writes conservation biologist David Wilcove of Princeton University in his book No Way Home: The Decline of the World's Great Animal Migrations. Already, many of the world's largest migrations are gone: the million-bird flocks of passenger pigeons and hundreds of thousands of bison that roamed North America, the right whale that swam along the western coast of Europe, and the springbok gazelle that crossed South Africa.
The impact of these losses are unknown, but the ecosystem of the Pacific Northwest is surely suffering from the lack of nutrients caused by the decline of salmon runs from as much as 500 million pounds (226 million kilograms) of fish to as little as 26.5 million pounds (12 million kilograms) today—these rivers now receive a mere 6 to 7 percent of the nitrogen and phosphorus they once enjoyed. The situation is so dire, Wilcove and his colleague Martin Wikelski (who has attached tiny sensors to select dragonflies to understand how even insects migrate) write in a recent issue of PLoS Biology, that measures must be taken now before they disappear.
But maybe not for much longer—thanks to ongoing habitat destruction, the creation of obstacles such as fences or dams, overusing natural resources, and climate change.
So writes conservation biologist David Wilcove of Princeton University in his book No Way Home: The Decline of the World's Great Animal Migrations. Already, many of the world's largest migrations are gone: the million-bird flocks of passenger pigeons and hundreds of thousands of bison that roamed North America, the right whale that swam along the western coast of Europe, and the springbok gazelle that crossed South Africa.
The impact of these losses are unknown, but the ecosystem of the Pacific Northwest is surely suffering from the lack of nutrients caused by the decline of salmon runs from as much as 500 million pounds (226 million kilograms) of fish to as little as 26.5 million pounds (12 million kilograms) today—these rivers now receive a mere 6 to 7 percent of the nitrogen and phosphorus they once enjoyed. The situation is so dire, Wilcove and his colleague Martin Wikelski (who has attached tiny sensors to select dragonflies to understand how even insects migrate) write in a recent issue of PLoS Biology, that measures must be taken now before they disappear.
VANISHING IN THE WILD: THE ELEPHANT
Throughout history, the elephant has played an important role in human economies, religion, and culture. The immense size, strength, and stature of this largest living land animal has intrigued people of many cultures for hundreds of years. In Asia, elephants have served as beasts of burden in war and peace. Some civilizations have regarded elephants as gods, and they have been symbols of royalty for some.
Elephants have entertained us in circuses and festivals around the world. For centuries, the elephant's massive tusks have been prized for their ivory.
The African elephant once roamed the entire continent of Africa, and the Asian elephant ranged from Syria to northern China and the islands of Indonesia. These abundant populations have been reduced to groups in scattered areas south of the Sahara and in isolated patches in India, Sri Lanka, and Southeast Asia.
Demand for ivory, combined with habitat loss from human settlement, has led to a dramatic decline in elephant populations in the last few decades. In 1930, there were between 5 and 10 million African elephants. By 1979, there were 1.3 million. In 1989, when they were added to the international list of the most endangered species, there were about 600,000 remaining, less than one percent of their original number.
Asian elephants were never as abundant as their African cousins, and today they are even more endangered than African elephants. At the turn of the century, there were an estimated 200,000 Asian elephants. Today there are probably no more than 35,000 to 40,000 left in the wild.
Tiger decline caused by the reduction of large ungulate prey: evidence from a study of leopard diets in southern India
There are currtly about 5,000 tigers left in the wild, and the Worldwide Fund for Nature says that poachers kill at least one of the magnificent cats every day. That means that some breeds of tiger in Asia will be extinct by the end of the century.
A market in Phnom Penh, Cambodia, is one of the few places in the world where tiger skins are sold in an open shop. Cambodia -- still emerging from the ravages of civil war -- is one of the world's poorest nations, with many priorities. Enforcing poaching laws is not one of them.
Wildlife preservation groups struggle against the odds to protect the tigers. At one zoo, Marshall Perry of Wildlife Preservation Cambodia points out a young tiger, confiscated from poachers. The cat will not be returned to the wild, because if he were, he would be recaptured within weeks.
"Most of the animals here at this zoo have been confiscated from illegal hunters and people trying to ship them out of the country," Perry says.
A dead tiger can fetch around $10,000 on the black market, where most of the animal's body parts are used for traditional Chinese medicines. Dried tiger genitals, for example -- thought to have aphrodisiac properties -- sell for around $4,000.
By 1998, the Chinese year of the tiger, the South China breed will be nearly extinct.
"I'm hoping that in the year of the tiger, the traditional Chinese medicine community will ask users to stop using tiger products until the tiger numbers recover," says Elizabeth Kemf of the World Wildlife Fund. (119K AIFF sound or 119K WAV sound)
But some Asian experts believe that the only way to save the tiger is to establish tiger farms. One such farm in Thailand has bred 35 animals and would like to farm tiger products. The Thai government, however, has so far refused to let it kill any of the animals.
"If you want to relieve the pressure on wild tigers being hunted, you need to set up a captive breeding operation," said Dr. Parntep Ratanakorn, a Thai wildlife adviser.
Others say it's not that simple, that the effect may be just the opposite of what is intended.
"Tiger farming should be banned because it would accelerate the trade in tigers," said Valmik Thapar of the Wildlife Institute of India. (230K AIFF sound or 230K WAV sound) Thapar said that he fears the introduction of tiger farms will put his country's tiger population -- 60 percent of the world's tigers live in India -- at greater risk.
A market in Phnom Penh, Cambodia, is one of the few places in the world where tiger skins are sold in an open shop. Cambodia -- still emerging from the ravages of civil war -- is one of the world's poorest nations, with many priorities. Enforcing poaching laws is not one of them.
Wildlife preservation groups struggle against the odds to protect the tigers. At one zoo, Marshall Perry of Wildlife Preservation Cambodia points out a young tiger, confiscated from poachers. The cat will not be returned to the wild, because if he were, he would be recaptured within weeks.
"Most of the animals here at this zoo have been confiscated from illegal hunters and people trying to ship them out of the country," Perry says.
A dead tiger can fetch around $10,000 on the black market, where most of the animal's body parts are used for traditional Chinese medicines. Dried tiger genitals, for example -- thought to have aphrodisiac properties -- sell for around $4,000.
By 1998, the Chinese year of the tiger, the South China breed will be nearly extinct.
"I'm hoping that in the year of the tiger, the traditional Chinese medicine community will ask users to stop using tiger products until the tiger numbers recover," says Elizabeth Kemf of the World Wildlife Fund. (119K AIFF sound or 119K WAV sound)
But some Asian experts believe that the only way to save the tiger is to establish tiger farms. One such farm in Thailand has bred 35 animals and would like to farm tiger products. The Thai government, however, has so far refused to let it kill any of the animals.
"If you want to relieve the pressure on wild tigers being hunted, you need to set up a captive breeding operation," said Dr. Parntep Ratanakorn, a Thai wildlife adviser.
Others say it's not that simple, that the effect may be just the opposite of what is intended.
"Tiger farming should be banned because it would accelerate the trade in tigers," said Valmik Thapar of the Wildlife Institute of India. (230K AIFF sound or 230K WAV sound) Thapar said that he fears the introduction of tiger farms will put his country's tiger population -- 60 percent of the world's tigers live in India -- at greater risk.
