Originally published in the Fall 2004 Lincoln Park Zoo magazine
Of the 230 species exhibited at Lincoln Park Zoo, 38 are listed as threatened or endangered by the United States Endangered Species Act. Of these 38 species, the eight precious gems profiled here are among the most decimated animal populations in the world.
Guam Micronesian kingfisher (Halcyon cinnamomina cinnamomina)
Status: Extinct in the wild. There are 74 Guam Micronesian kingfishers in the world. The zoo houses 10.
Distribution: Pacific island of Guam.
Cause: Invasive alien species. The introduction of the brown tree snake during World War II decimated this bird, whose eggs are vulnerable to the snake.
Recovery Efforts: In the past year animals have been moved to a captive facility on Guam. Micronesian kingfishers had not been on the island since their disappearance in the mid-1980s. It’s a small first step, but if they breed well, their offspring may be released to the wild. In addition, the zoo has been involved with kingfisher recovery projects since the early 1990s. Director of Conservation Biology Joanne Earnhardt, Ph.D., is a member of the U.S. Fish & Wildlife Service Recovery Team. The zoo is also a leader in kingfisher breeding. Five hatchlings are developing off-exhibit at the McCormick Bird House.
Guam rail (Rallus owstoni)
Status: Extinct in their native habitat. An experimental population of approximately 250 birds lives on the nearby island of Rota. There are 100 Guam rails in captivity around the world, four at the zoo.
Distribution: Pacific islands of Guam and Rota. While not part of its historic range, Rota was chosen for introductions due to proximity to Guam and the absence of predators or competing species.
Cause: Invasive alien species. The introduction of the brown tree snake during World War II decimated this flightless bird, whose eggs are vulnerable to the snake.
Recovery Efforts: The zoo’s Hope B. McCormick Curator of Birds Megan Ross, Ph.D., is the American Zoo & Aquarium Association’s Species Survival Plan (SSP) coordinator for the Guam rail. She has visited the rail rehabilitation center on the island and oversees the breeding plan for all the rails in North America. Ross also works with population biologist Colleen Lynch of the Population Management Center, and wildlife staff from Guam to determine which individuals are suitable for wild reintroductions. One bird is being considered for reintroduction in the coming months.
Virgin Island boa (Epicrates monensis granti)
Status: Endangered. The Regenstein Small Mammal-Reptile House has three Virgin Island boas off-exhibit in conditions that mirror wild habitats, in the hope they will produce offspring.
Distribution: Puerto Rico and surrounding islands.
Cause: Invasive alien species, human encroachment. Virgin Island boas are killed by feral cats, the Indian mongoose and rats. Development on the main island of Puerto Rico has destroyed portions of the snake’s habitat.
Recovery Efforts: Since 1993 the zoo has participated in the Virgin Island Boa SSP, which has prompted surveying the native islands in search of new populations and scouting potential new habitats for displaced boas. In 1997 the zoo’s boas produced four offspring, two of which were released to the wild in Puerto Rico a year later.
Aruba Island rattlesnake (Crotalus durissus unicolor)
Status: Critically endangered. The zoo houses five male Aruba Island rattlesnakes.
Distribution: Aruba Island in the Caribbean.
Cause: Human development, including tourism, on Aruba.
Recovery Efforts: The zoo is one of 35 participants in the Aruba Island Rattlesnake SSP, which manages 130 animals. The target is 175, a number that would maintain 95 percent genetic diversity in the captive population for the next 100 years. The SSP initiatives include programs for Aruba’s educators, support of the island’s Arikok National Park and creating a field research project to determine the effect of competing species on the rattlesnake’s survival.
Amur leopard (Panthera pardus orientalis)
Status: Critically endangered. There are as few as 40 Amur leopards in the wild. The zoo houses two of the fewer than 200 captive cats worldwide.
Distribution: Along the Amur River, which cuts across the border of China and Russia.
Cause: Loss of prey, human encroachment and poaching. A decrease in prey species, including wild boar, deer and rodents, has decimated this population.
Recovery Efforts: The zoo participates in the American Zoo and Aquarium Association’s Amur Leopard Population Management Plan.
African wild dog (Lycaon pictus)
Status: Endangered. Only 3,000 to 5,500 remain in the wild.
Distribution: Wild dogs numbering in the hundreds of thousands once roamed most of the African continent but are now relegated to small pockets throughout.
Cause: Human encroachment, disease, accidental mortality, hunting. As their access to prey diminishes due to shrinking territory, their interaction with humans increases, resulting in fatal encounters with cars or persecution by herders, who fear wild dogs will kill livestock.
Recovery Efforts: The zoo is studying the social interaction of its three female dogs and monitoring the introduction process of a male in order to better understand captive-pack information and refine captive-management techniques. The data will complement zoo-supported research being conducted in Kenya.
Drill (Mandrillus leucophaeus)
Status: Endangered. The drill is the most endangered of all African primates.
Distribution: Cameroon, Equatorial Guinea (Bioko), Gabon, Nigeria.
Cause: Habitat loss, human encroachment, poaching, bushmeat trade. The species lives in areas rich with colombo-tantalite ore, or coltan, a key metallic ingredient used in the manufacture of cell phones. As the demand for coltan increases, the drill will continue to be displaced unless rescue efforts are implemented. Compounding these problems is the drill’s nature. Unlike other species, male drills do not run when threatened. They stare down their attackers, baring impressive fangs and hissing in a manner that successfully scares off wild foes, but dooms the species when facing down the barrel of a gun.
Recovery Efforts: Research Biologist Lisa Faust and Director of Conservation Biology Joanne Earnhardt, Ph.D., developed the Population Management Plan for the Nigerian drill population. The zoo has also provided financial support to maintain that captive population with the intent to reintroduce animals to the wild.
Arabian oryx (Oryx leucoryx)
Status: Endangered. The zoo houses four.
Distribution: Formerly throughout the desert terrain of the Middle East, small populations still remain in reintroduction sites in their native land.
Cause: Illegal capture for sale to private collectors, reduction of habitat due to drought and overgrazing, and poaching. Illegal hunting is loosely mastered in the Middle East; many consider hunting oryx a vested right. By 1972 the species had been eradicated from the wild by poachers who killed the animals or sold them to private zoos.
Recovery Efforts: In the past 20 years 41 oryx have been born at the zoo, which donated four for reintroduction in the Middle East in the early 1990s. 
