By Jerilyn Watson and Shelley Gollust / Broadcast: Tue, 5 Jun 2007 16:00:00 UTC

　　VOICE ONE:

　　I'm Steve Ember.

　　VOICE TWO:

　　And I'm Barbara Klein with EXPLORATIONS in VOA Special English. Today we tell about the National Wildlife Refuge System that protects wildlife in the United States.

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　　VOICE ONE:

　　In nineteen-oh-three, the twenty-sixth president of the United States heard about a

　　Pelican Island National Wildlife Refuge

　　small island in the state of Florida that had many birds. President Theodore Roosevelt was told that hunters were killing most of the pelicans on the island. He soon decided the nation should protect these beautiful water birds.

　　President Roosevelt declared the island the first federal protection area for birds. This refuge was named the Pelican Island Reservation. It was established on a very small piece of land in the Indian River Lagoon, near the Atlantic Ocean. The island became the first protected area in what later would become the huge National Wildlife Refuge System.

　　VOICE TWO:

　　Today the Wildlife Refuge System is the world's largest land network for managed and protected wildlife. The refuge system is part of the United States Fish and Wildlife Service. Among other duties, the system enforces the Endangered Species Act. This law protects wildlife threatened with disappearing from Earth. Wildlife refuges also help the environment. They help protect wetlands that control flooding and pollution.

　　VOICE ONE:

　　The refuge system has more than five hundred forty centers. They cover more than thirty-eight million hectares of land and water. Most are open to the public. More than thirty-nine million people visit them every year. Visitors can fish and hunt at more than half of these wildlife centers.

　　Activists say the refuge system is one of the nation's greatest successes in protecting nature. National wildlife refuges exist in all fifty states and twelve American territories and possessions. Almost all the refuges contain water. Many of these refuges include national parks.

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　　VOICE TWO:

　　Theodore Roosevelt served as president from nineteen-oh-one to nineteen-oh-nine. During that time he created fifty-one bird refuges in seventeen states and three territories. He also created five national parks and one hundred fifty national forests. Historians say it is especially interesting that President Roosevelt did this. The energetic former soldier was known for hunting large animals. History remembers him as one of America's most important activists for wildlife.

　　VOICE ONE:

　　Before President Roosevelt declared Pelican Island a wildlife refuge, both Florida and the federal government had tried to protect America's wildlife. Congress had enacted two laws aimed at wildlife protection. In eighteen sixty-nine, the lawmakers created a protected area in the Pribilof Islands of Alaska. The goal was to give seals a safe place to have their babies.

　　In eighteen ninety-four, Congress made it illegal to harm wildlife inside the huge Yellowstone National Park in the western part of the country.

　　VOICE TWO:

　　In nineteen-oh-one, a Florida law prevented shooting birds on Pelican Island for their feathers. But people disobeyed this law until President Roosevelt intervened. Some other animals were already threatened with disappearance when President Roosevelt took the first step toward a national conservation agency.

　　For example, many bison had lived in the western part of the country. But by the nineteenth century, hunters had killed hundreds of thousands of these big animals.

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　　VOICE ONE:

　　Over the years the birds on Pelican Island have survived many threats. Human activities on the water produced waves that reduced the island's shorelines. The island decreased to half its size. In nineteen sixty-eight, the refuge was expanded to protect nearby islands and wetlands.

　　In two thousand, the Fish and Wildlife Service and other agencies and businesses provided money to restore the refuge. Mangrove trees and plants natural to the area replaced plant life that did not belong there. A lake was added. Experts restored tidal wetlands and a forest.

　　VOICE TWO:

　　To protect the island, visitors now watch the birds from the Centennial Trail on nearby land. A tower also was added so people can look at Pelican Island from above. Not long ago, a visitor was watching the island late in the day. Many huge birds were spreading their wings and floating against the darkening sky. The visitor said she will never forget that sight.

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　　VOICE ONE:

　　Last month, the Fish and Wildlife Service announced its great success protecting America's most famous bird. It announced results showing the largest population of breeding bald eagles in the United States since the nineteen forties.

　　In nineteen sixty-three, there were only four hundred seventeen nesting pairs of bald eagles in the lower forty-eight states. This was an all-time low. Today, there are an estimated nine thousand seven hundred eighty-nine breeding pairs. This is an all-time high. Nesting or breeding pairs are a male and female that are able to reproduce.

　　You can find wild bald eagles in every state in the lower forty-eight states and in the District of Columbia. The state of Minnesota has the largest number of pairs of eagles, followed by Florida and Wisconsin. The three states all have more than one thousand pairs.

　　VOICE TWO:

　　The bald eagle is a large brown bird with a white head and tail. It is the national bird of the United States. The bald eagle is on the Great Seal of the United States, the presidential flag and the back of the dollar bill.

　　The bald eagle has been protected as a threatened species under the Endangered Species Act. The Fish and Wildlife Service says the bird needed protection because it was threatened by the widespread use of DDT, a chemical that kills insects.

　　VOICE ONE:

　　Starting in the nineteen forties, DDT was used to control mosquitoes and insects harmful to agriculture. When it rained, DDT washed off the soil and into waterways. There, plants and animals took in the chemical. Fish ate the plants and animals. And eagles ate the fish. DDT built up in the fatty tissues of female eagles. This prevented the formation of calcium needed to make strong eggshells. The female eagles produced eggs. But the eggshells were thin and broke when the birds sat on them to keep them warm.

　　VOICE TWO:

　　Rachel Carson was a biologist and writer for the Fish and Wildlife Service until nineteen fifty-two. She recognized the dangers of insect-killing chemical products, including DDT. But she also knew that the agriculture industry needed such pesticides for crop production.

　　In nineteen sixty-two, Carson produced a book, "Silent Spring," after years of research in the United States and Europe. It examined the effects of DDT and other pesticides on the health of people and animals. The book became a best-seller. And it caused fierce debate. In nineteen seventy-two, the United States banned the use of DDT.

　　VOICE ONE:

　　Rachel Carson's book "Silent Spring" launched the environmental protection movement in the United States. But she did not live to see it. She died in nineteen sixty-four.

　　May twenty-seventh was the one-hundredth anniversary of the birth of Rachel Carson. Many activities are being carried out across the United States to celebrate her life and work as an educator, scientist and writer.

　　The Fish and Wildlife Service is also celebrating the recovery of the bald eagle. The service is taking steps to remove the national bird from the federal list of threatened and endangered species under the Endangered Species Act.

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　　VOICE TWO:

　　This program was written by Jerilyn Watson and Shelley Gollust. Mario Ritter was our producer. I'm Barbara Klein.

　　VOICE ONE:

　　And I'm Steve Ember. You can download transcripts and audio archives of our programs on our Web site, www.unsv.com. Join us again next week for Explorations in VOA Special English.

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