The Tragedy of the White Tiger

The white tiger is produced by a genetic fluke that occurs when two orange tigers with rare recessive forms of a gene, called alleles, happen to breed. White tigers in the wild are so rare that they have only been seen a handful of times in recorded history, with the last known wild white tiger killed in 1958. Scientists dispute whether their rarity is because the recessive allele is the result of a one-time mutation or because white tigers lack adequate camouflage, negatively affecting their ability to stalk prey or avoid other predators.

The sad truth, though, is that white tigers now represent a grossly disproportionate segment of the captive tiger population relative to their prevalence in wild populations. Because they are so rare, exploitative roadside menagerie operators, exhibitors and collectors seek to maintain white tiger populations for the sake of generating profit. To continue producing white tigers, captive tigers with this rare allele expression are intensively inbred over multiple generations. In other words, parents are bred with their offspring, siblings are bred with one another, and other closely related animals are bred with one another as well. In fact, all of the white tigers in captivity in the U.S. are believed to be descendants of a single male Bengal tiger named Mohan.

Captured as a cub by a hunting party in 1951, Mohan was bred to an orange tiger and then to his daughter from that breeding. This inbreeding resulted in the birth of a tigress named Mohini—one of two white tigers in the litter of four produced by Mohan and his daughter. Mohini was gifted to the Smithsonian National Zoo in 1960, and then bred to her half-brother (an individual who was also her uncle), and then to her son from that litter to create more white tigers.

The unscientific practice of continual inbreeding continues to this day, not by zoos accredited by the American Association of Zoos and Aquariums (AZA)like the Smithsonian National Zoo—but primarily by largely unregulated commercial enterprises who use white tigers as a draw for paying visitors. More than 60 years since Mohan and 11 tiger generations later, white tigers are suffering the consequences of extensive inbreeding, which has produced tragic results.

Because of the resultant reduced biological fitness known as “inbreeding depression,” white tiger cubs experience a high rate of neonatal mortality. For intensively inbred animals, over 80 percent of cubs pass away shortly after birth. White tigers also experience reduced litter size and shorter average life spans, are prone to impaired vision, cardiac defects, serious spinal and facial deformities, and compromised immune systems. In 2011, the AZA ended the practice of breeding white tigers, citing the “abnormal, debilitating, and at times lethal external and internal conditions and characteristics” resulting from breeding wild animals to increase the frequency of rare alleles.

Pseudosanctuaries—exploitative, unqualified wildlife exhibits masquerading as legitimate rescue sanctuaries—continue to breed and abuse white tigers under the guise of conservation. This is a far cry from true conservation. Indeed, captive-bred white tigers serve absolutely no conservation or education purpose. Their lack of genetic diversity, high degree of inbreeding and resultant physical afflictions remove these animals and their offspring from consideration for any hypothetical release programs. These animals have no place in any conservation program, which explains why no legitimate conservation organization today endorses the breeding of white tigers.

The only reason white tigers are bred today is because they are incredibly lucrative for breeders and exhibitors alike who charge visitors at entertainment venues to play with cubs, using them as photo props. Once cubs used for direct contact displays age out of this vicious pay-for-play system, they may be sold to the general public as “pets,” warehoused, intensively bred to create the next generation of money-making white tiger cubs or otherwise subjected to inhumane treatment. When the unsuspecting public buys into an exhibitor’s false conservation claims and pays to see or handle a white tiger, they are unknowingly perpetuating irresponsible inbreeding, poor population management and inhumane practices.

Currently, federal legislation has been introduced in the U.S. Senate including the Big Cat Public Safety Act (H.R. 263/S. 1210), striking a blow to the key financial driver behind the incessant and highly unregulated breeding of big cats and the resultant proliferation and “breeding to death” of white tigers.

Pop culture has romanticized the keeping and breeding of tigers and other big cats in a terribly harmful way. Hopefully our collective eyes are now open to what we need to do to ultimately protect these iconic animals from their greatest threat: us.

This is an opinion and analysis article; the views expressed by the author or authors are not necessarily those of Scientific American.



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