The white tiger is a rare pigmentation variant of the Bengal tiger. White tigers lack the pheomelanin pigment that normally gives a tiger its orange coloration, but they still produce the lighter eumelanin, and are therefore not considered to be albinos (i.e., deficient in all forms of skin pigment).
In the wild, it is rarely sighted, but thanks to demand from exotic pet stores and zoos in recent decades, breeders have been attempting to create what they deem to be the “ideal” white tiger, by drawing on a limited gene pool of white tigers that are in captivity. This limited gene pool has led to a high rate of health problems and deformities among these captive tigers’ offspring.
In one sense, the white tiger scenario represents just one part of a larger issue affecting captive breeding programs everywhere. For example, zoo animals in the U.K. were deemed to be “genetic disasters” by conservation geneticist Dr. Paul O’Donoghue back in December. O’Donoghue stated that the pedigrees of many zoo animals had become contaminated by hybridization with different but related species, “sharing more DNA than if they were cousins … it is clear that people who visit zoos to see iconic animals are often looking at hybrids which have zero conservation value.”
While O’Donoghue’s report focused on U.K. zoos, it has disturbing ramifications for captive breeding programs around the world. One of the main arguments put forward in support of captive breeding programs is that such efforts aid conservation purposes by providing a stable population of animals who are endangered in the wild, that can later be released when conditions are favorable. However, the disadvantage of these schemes is that they are often implemented at the cost of a species’ overall genetic diversity.
Nowhere is this more apparent than in the case of white tigers, who are considered by Big Cat Rescue to “serve no conservation purpose” for aiding the survival of the world’s tiger population.
Problems Faced by White Tigers
Many white tigers who are inbred in this way are prone to crossed eyes (otherwise known as strabismus), due to incorrectly routed visual pathways in the brains of such tigers. When stressed or confused, all white tigers cross their eyes. Strabismus is thought to be directly linked to the white gene and is not a standard consequence of inbreeding, as the orange cubs of white tigers are not prone to crossed eyes.
Other health problems that arise within captive-bred white tiger populations include crooked backbone or neck, shortened legs, club foot, organ problems, and reduced fertility. Vascular ring anomaly in the throat and stomach has also been reported among these animals. This severely impairs their ability to swallow and digest food, and usually requires an operation for correction and survival.
Case Study: Kenny
Kenny was “selectively inbred” by a private breeder in the U.S., and is believed to have been born in 1998. His parents were a brother and sister who both carried the recessive gene for whiteness, meaning that Kenny acquired double recessive genes from them. He was left with multiple developmental defects, and was considered to be the first tiger with Down’s Syndrome. In 2000, he was rescued by the Turpentine Creek Wildlife Refuge in Eureka Springs, Ark., and lived there until his death of cancer in 2008.
Case Study: Mohan
Mohan was a resident of Crown Ridge Tiger Sanctuary in Farmington, Mo. He was the father of two other Crown Ridge residents, the orange tigers Thor and Gracie (who was born 90 to 95 percent blind). He recently passed away at the age of twenty, of kidney failure and severe arthritis. During his life, he had also been cross-eyed. The staff of Crown Ridge say that he touched their hearts with his “unique personality” and “his unforgettable old man groans.”
Case Study: Zabu
Zabu is a female white tiger who currently lives at the Big Cat Rescue center in Tampa, Fla. She was born in 2000, at a circus and roadside zoo in New England that has thankfully closed down. This zoo intended to cross breed Zabu with their resident male lion, Cameron, in order to produce an unhealthy lion-tiger hybrid known as the liger.
She and Cameron were rescued in 2003, and subsequently neutered. The two are reportedly best friends, with Cameron preferring to laze around all afternoon, while Zabu “is extremely energetic and is always pestering him to play.” Zabu was born with a cleft palate, meaning that she sometimes has difficulty swallowing food.
Big Cat Rescue claimed that they had to think very carefully about taking in Zabu, because they “didn’t want to be perceived as using a white tiger to draw visitors,” thereby perpetuating the myth of white tigers as alluring or exotic. However, Zabu’s urgent need to be rescued overrode these concerns.
Is There a Solution?
Zoological researcher Dan Laughlin has this to say on the subject of white tigers: “The only conceivable legitimate reason for exhibiting a white tiger would be for educational purposes to clearly and unequivocally demonstrate to the public the process of natural selection and how, when a deleterious recessive genetic mutation randomly occurs that is disadvantageous for the survival of the animal, such as white color in a tropical jungle environment, the animal does not survive to pass on that genetic mutation or disadvantageous characteristic to its offspring.”
This stance is also held by the American Zoological Association (AZA). In 2008, AZA recognized that white tigers should not be bred, and instructed AZA accredited zoos not to breed any more of them.
Speaking of this decision, they said, “At times, inappropriate breeding practices by others (outside of AZA) may yield animals with anomalous phenotypes and adverse internal conditions, which may be in need of rescue. Providing holding and care for such animals and responding to rescue requests from local, state, or federal agencies are appropriate activities for AZA-accredited institutions, provided that the delivery of thoughtful educational messages about the unfortunate results of intentional inbreeding for rare genetic traits are part of any public display.”
The current scientific consensus on white tigers is that their breeding should be discontinued, and they should instead be permitted to “go extinct.” Many members of the public have been misinformed on the truth behind white tigers, believing them to be a separate subspecies in need of conservation (the term “Royal White Tiger” has been thrown around by some groups).
You can help educate friends and family on the truth by sharing this article, or by directing them to information from reputable tiger protection or conservation groups such as Big Cat Rescue. Above all, do not support any theme park that displays a white tiger for profit, and discourage others from doing so too.
Image Source: Michael Gwyther-Jones/Flickr