The Galapagos giant tortoise calf that just hatched at the Tropiquarium de Servion in Switzerland is extremely rare. The reason for her peculiarity is that she is albino, totally white, except for her eyes, which are red. According to zookeepers, the odds of a tortoise being born with this genetic disorder is 1 in 100,000.
On February 11, a giant tortoise weighing 100 kilos laid two eggs. The albino calf was born on May 1 and her darker sister four days later. Both turtles weighed just 50 grams at birth and had to go through the incubator, before being reunited with their mother on June 3, according to the Reuters news agency.
“We were surprised to discover an albino baby,” zoo staff wrote in a statement. “It is the first time in the world that an albino Galapagos tortoise is born and kept in captivity,” and there are no documented cases in the wild, they added. The team also noted that the birth of an albino turtle could be up to five times rarer than the birth of an albino human, which has a chance of about 1 in 20,000 people, according to the National Organization for Albinism and Hypopigmentation. a nonprofit organization that provides information and resources about albinism to people in the United States and Canada.
When an animal is albino, its body cannot produce melanin , which is the pigment that gives color to skin, hair, feathers and eyes. In the case at hand, it would also color the shell of the turtle. Albino animals often have red eyes. This is so because they lack pigment and therefore are the same color as the blood vessels below the surface of the eyes.
It is not known how many years the newborn albino calf will live because, although the giant tortoises of the Galapagos have a life experience of more than 100 years when they are free, their special condition makes their existence difficult . Albinism makes animals more exposed to the sun’s ultraviolet rays and predisposes them to reduced vision and hearing difficulties. Also, the white color makes them an easy target for predators. As a consequence of all of the above, albino animals do not usually live long and die before they can transmit their genes, which explains why this disease is so rare. In captivity and with proper care they can live in relative health.
The breeding of giant tortoises in captivity
It all begins with the mating of the female and the male, a ritual that is anything but loving. Before mounting the female, the male rams the female’s shell over and over again with his own. It also bites their legs. During the act, in addition, the male emits very loud moans. In fact, this inspired the creators of the Game of Thrones series to create the roars of dragons.
The sex of future turtles will be determined by the temperature at which the eggs are incubated. According to the San Diego Zoo, in this species, warmer conditions cause the tortoises to develop into females, and cooler temperatures produce males. The sex of the newly hatched tortoise pair is not yet known, as there are currently no physical differences between males and females.
In the wild, the young seem to “disappear” until they are about five years old. The researchers aren’t sure where they go, but they suspect that the juvenile tortoises spend their first few years hiding in the forest undergrowth to avoid their only natural predator: the Galapagos hawk ( Buteo galapagoensis ). No one knows exactly how these early years go. Of course, when they reappear they are already too heavy to be transported by one of these birds.
Captive breeding can be a very useful tool to conserve these huge tortoises , which have seen their numbers decline in the wild. Wild tortoise populations in the Galapagos were severely affected by early European explorers, whalers, and naval crews, who hunted them as a source of oil and food for long voyages across the seas. Scientists believe that there used to be about 200,000 giant tortoises on the Galapagos Islands, which, by the way, get their name from the tortoises (the word “Galapagos” comes from an archaic Spanish word for “tortoise”), but now there are only about 15,000, according to the Galapagos Islands Trust.
