and cultural reasons, such as overhunting of the American bison, Arabian oryx, white rhinoceros, and American beaver. Or it may happen for correctable environmental reasons, such as introduced pesticides (the peregrine falcon and bald eagle) and introduced predators and competitors (the Hood island giant tortoise and Howe Island wood rail). And the loss may also last for unpredictably long periods, as with the Pere David’s deer, Mongolian wild horse, European wisent, perhaps the Siberian tiger, brown-eared pheasant, Mauritius pink pigeon, and Guam rail; it could even be forever. But populations of all these species and many more have been increased in one situation or another by intervention strategies (see Table 30–1).

Where a wild population’s ability to survive is lost, especially where the threat and destruction may be temporary, e.g., for the American bison, peregrine falcon

TABLE 30–1 Ex Situ Care and Biotechnology. Each Technique Has Been Utilized with the Species Listed Below It on a Long-Term or Experimental Basis

Intervention Technique


Short-term propagation and reintroduction

Golden lion tamarin, cheetah, wolf, red wolf, American and European bison, Arabian oryx, onager, Andean condor, bald eagle, peregrine, Hawaiian goose, Lord Howe Island wood rail, Guam rail, European eagle owl, Guam kingfisher, Galapagos giant tortoise, Galapagos land iguana, Ash Meadows Amargosa pupfish

Long-term propagation

Lion-tailed macaque, Siberian tiger, Pere David’s deer, European bison, Przewalski horse, brown-eared pheasant, Edward’s pheasant, Bali myna, white-naped crane, addax, slender-horned gazelle, scimitar-horned oryx, gaur, Gérevy’s zebra, Puerto Rican horned toad, Chinese alligator, Mauritius pink pigeon, Madagascar radiated tortoise, Aruba Island rattlesnake

Relocation, transplantation

Koala, mongoose lemur, aye-aye, brown lemur, chimpanzee, gorilla, squirrel monkey, wooly monkey, spider monkey, common marmoset, black rhinoceros, white rhinoceros, red deer, white-tailed deer, mule deer, moose, Tule elk, bighorn sheep, musk-ox, pronghorn antelope, roan antelope, mountain goat, African elephant, more than 400 species of birds, many reptiles and amphibians

Fostering, cross-fostering

Peregrine, bald eagle, whooping crane, masked quail, polar bear (captive), many species of waterfowl, pigeons, cranes (in nature and captivity), and passerine birds in captivity

Artificial incubation

Gharial, Siamese crocodile, Chinese alligator, green turtle, ridley, hooded crane, whooping crane, white-naped crane, and many other birds, reptiles, amphibians, and fishes

Artificial rearing

Hundreds of species of most vertebrate groups

Artificial insemination

Alligator, ocellated turkey, brown-eared pheasant, whooping crane, squirrel monkey, yellow baboon, giant panda, guanaco, Speke’s gazelle, gemsbok, bighorn sheep

Embryo transfer

Gaur, bongo, eland, common zebra, Przewalski horse, cottontop marmoset, yellow baboon

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