Captive breeding

DEFINITION: Selective breeding of an endangered or threatened species in captivity

Captive breeding is sometimes the only way to save a species from extinction. Captive-bred animals are often returned to their native habitats once their populations have sufficiently recovered and the animals have been properly conditioned to survive in the wild.

As conditions in zoos steadily improved throughout the twentieth century and captive animals began breeding, scientists realized that the breeding of threatened and endangered species in captivity could save some species that would otherwise become extinct. Many zoos began to shift their priorities from entertainment to wildlife conservation in the late 1970s.

Initially, zoo animals were allowed to breed without consideration of their genetic or health status—the only guiding principle involved was “more is better.” Zoo populations, however, are far too small to sustain healthy breeding; depending on the species, a healthy breeding population might range from seventy-five to four hundred animals. The inbreeding that resulted from early zoo policies led to fewer offspring, increased rates of congenital abnormalities, and susceptibility to disease. In response, the Association of Zoos and Aquariums established the Species Survival Plan (SSP) in 1981 to increase the number of animals in the breeding pool. A computerized mating system, the SSP maintains genetic records of all captive animals of particular species, allowing zoos to exchange animals without fear of inbreeding. Into the mid-2020s, there were nearly 300 SSP programs covering hundreds of species.

In the 1990s, captive breeding began to lose some of its appeal as the costs began to outweigh the benefits. In vitro fertilization of gorillas can cost up to $75,000, and the cost of the California Condor Recovery Plan was an estimated $20 million between 1974 and the late 1990s. Critics of captive-breeding programs—and zoos in general—argue that such large amounts of money could be better spent preserving animals’ natural habitats. Opponents of the US Endangered Species Act (1973) have also used the existence of captive-breeding programs as an argument against habitat protection laws.

Another drawback of SSPs and captive breeding in general is the problem of surplus animals. Breeding endangered species may be a good public relations tactic, but the culling of surplus animals is definitely not. One large issue faced by captive-breeding programs is what is to be done with animals that are genetically inferior or past breeding age, or those that have been hybridized in ways that would contaminate the gene pool. Contraceptive implants and separation are two common solutions, but some surplus animals end up in game parks and hunting preserves.

Despite its drawbacks, captive breeding remains the only option for some species, the most famous of which is the California condor. In an extraordinary measure of intervention, the last nine known condors in the wild were captured in 1985, bringing the total number in captivity to twenty-seven. By 1992, captive breeding had brought the population up to 134, and scientists gradually began returning birds to their natural habitat. By the mid-2020s, around 561 condors were known to be living, 347 of them in the wild. Other species that have been saved by captive breeding include the black-footed ferret, the Arabian oryx, Przewalski’s horse, and Père David’s deer; the first three of these have been reintroduced, in limited numbers, into their original habitats.

Captive Breeding in Amusement Parks

Zoos are not the only amusement venues that breed in captivity or that have come under fire for their practices. Most aquariums, for example, breed their freshwater fish in captivity. Saltwater fish have proven more difficult to breed in captivity. Into the mid-2020s, about 98 percent of saltwater fish were still caught in the wild, with grave effects on the coral reefs where many of them lived. In the cases of these species, breeding in captivity could ultimately have positive environmental effects.

There is, however, a very famous and controversial case of breeding marine life in captivity, that of SeaWorld and orca whales. SeaWorld has bred these animals in captivity for decades and trained them for performance in their shows. The group of theme parks had long been the target of criticism from animal rights groups, in particular the Humane Society of the United States (HSUS), for their treatment of their animals. On February 24, 2010, SeaWorld trainer Dawn Brancheau was killed by an orca named Tilikum, who was also involved in two previous trainer deaths. While Tilikum was not born in captivity, he was caught at the age of two and raised in captivity for over thirty years. Following the 2010 incident, a documentary was released in 2013, called Blackfish, that addressed the event and SeaWorld's treatment of their captive animals, the aggression of the animals against each other in captivity, and the appropriateness of keeping orcas at all. In March 2016, following the backlash of those concerned for the life of the whales and safety of their trainers, as well as decreased park attendance, SeaWorld announced that it would stop breeding orcas and phase out the theatrical performances using them. The last orca in SeaWorld born in captivity was in 2017; however, the parks have yet to phase out their orca shows, which the organization claimed focus on education, enrichment, natural behavior, and animal care.

Bibliography

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Tsui, Sherman. "Breeding Programs for Endangered Species: Do They Really Help?" Earth.org, 16 Aug. 2023, earth.org/breeding-programmes/. Accessed 18 Sept. 2025.

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