Endangered Species Handbook

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It's Too Late

Vertebrates

     Vertebrate extinctions worldwide since 1500 total at least 372 species of mammals, birds, reptiles, amphibians and fish.  The largest number ‒ 157 species ‒ were birds, while 100 mammal species, 28 reptile species, 6 amphibians and 81 fish species disappeared.  The number and rate of extinctions have increased gradually in recent centuries, as the table "Extinct Species of Birds, Mammals, Reptiles and Amphibians" illustrates.  Fewer than 80 of these vertebrates became extinct from 1500 through the 18th century, while in only the 19th century, 98 species of birds, mammals and reptiles died off.  The rate accelerated during the 20th century; based on incomplete information, at least 115 vertebrates — already 17 species more than in the past century — were lost.  (See Appendix for list of species and their dates of extinctions.)  This total will be far greater when the toll for the 20th century is finalized. 
 
     229 species, almost 80 percent of the 291 extinct mammals, birds, reptiles and amphibians, were native to islands, mostly located far from the nearest land mass, such as the Hawaiian Islands, Mascarene Islands and New Zealand.  (See Table “The Geography of Extinction.”)  Many of these island species were distinctive and unusual, the products of thousands and even millions of years of evolution in isolation.  Few left close relatives.
 
     Some islands are fragments of ancient continents, broken off more than 100 million years ago, with resident wildlife and plants.  New Zealand, Madagascar, the Seychelles and the larger islands of the Caribbean are examples of this phenomenon.  In exceptional circumstances, original inhabitants survived; some evolved into different forms, while others remained almost unchanged.  Additional plants and animals arrived by air, ocean current or clinging to masses of vegetation or floating logs, perhaps every thousand years.  Few of these survived, but occasionally these new colonists were able to adapt to the new environment and thrive.  Other islands were formed by volcanic eruptions or coral reefs growing atop extinct volcanoes. Virtually all native fauna and flora of these islands, which include the Hawaiian, Mascarene and Galapagos Islands, were colonizers.  The majority of extinct island species were flightless birds, tortoises and other species unable to flee when European ships and their crews arrived in search of commodities such as spices, timber and fur animals.  They were killed for food and sometimes found their habitats destroyed by logging or the many species of animals brought to the islands.  They were successful species in adapting to their environment and surviving for long periods, even radiating into entire new families of animals, but nothing had prepared them for the drastic changes humans caused, or the high mortality from hunting or persecution. 
 
     Sixty-two mammals, birds, reptiles and amphibians, as well as all but one of 81 species of fish, were native to mainland areas.  The continent with the largest number of non-fish extinctions is Australia, with 24 species, 22 of which were mammals, killed off by introduced animals and loss of habitat (see Mammals section in the table: “The Geography of Extinction”).  Non-native species caused the extinctions of many fish in the United States, Mexico and Africa.  Killing by persecution or commercial purposes, such as for furs, meat or sport, caused extinctions in Africa, North America, Australia, Europe and Asia.  Capture for pets and killing eliminated birds in the Caribbean, Australia and South America.  The clearing of forests eliminated a number of tropical birds in Asia and South America.  Elimination of wetland habitats was the major cause of the extinction of amphibians and fish, especially those that were ecologically isolated, such as cave fish or desert spring species. 
 
 
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Extinct Species of Birds, Mammals, Reptiles and Amphibians
1500 to present
100-Year Periods Mammals Birds Reptiles Amphibians Total
1500-1599 0 6 0 0 6
1600-1699 14 15 3 0 32
1700-1799 13 26 3 0 42
1800-1899 31 56 10 0 97
1900-2000 42 54 12 6 114
  ____ ____ ____ ____ ____
TOTALS 100 157 28 6 291
Source:  List of Extinct Species in the Appendix of this book.
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