Two Aldabra tortoises given to Singapore Zoo: 6 things about the gentle giants

Casela, one of two female Aldabra giant tortoises presented as a gift from Mauritius to Singapore.
Casela, one of two female Aldabra giant tortoises presented as a gift from Mauritius to Singapore.PHOTO: WILDLIFE RESERVES SINGAPORE

The Singapore Zoo has two new reptilian additions - a pair of female Aldabra tortoises, which are gifts from Mauritius to the Republic to commemorate a new air corridor that opened between the two countries last year.

The two tortoises, named Casela and Coco, were from the Casela World of Adventures nature park in Mauritius.

Aldabra giant tortoises, which originate from the island of Seychelles, are one of the largest land tortoises in the world.

Get to know the vulnerable reptile behind that hard, domed exterior:

1. From an even smaller island


Seychelles is known for its beautiful beaches and azure waters. PHOTO: SEYCHELLES TOURISM BOARD

The Aldabra is one of the last remaining species of giant tortoises alive today.

While many of their lumbering relatives were hunted and pushed to extinction by humans and their domesticated animals, the Aldabra tortoises were ensconced on the remote Aldabra atoll, part of the Seychelles chain in the Indian Ocean.

There are now an estimated 100,000 still on the island, but they are threatened by humans encroaching on their habitats, and by rising sea levels due to global warming.

2. Saved from extinction

The tortoises are listed as "vulnerable" in the International Union for Conservation of Nature Red List.

Charles Darwin and other conservationists initiated the protection of the tortoises in the late 1800s so they would avoid the tragic fate of the Galapagos tortoises.

There is also a captive population in Mauritius as some were moved there as part of conservation efforts.

3. Gentle giants


The Aldabra tortoise can grow to 250kg in weight and its shell can be as long as 1.2m. PHOTO: SEYCHELLES TOURISM BOARD

At full size, the male Aldabra tortoise can weigh up to 250kg and his carapace or upper shell can grow up to 1.2m long. Females are smaller at about 160kg and 90cm.

They eat mainly grass, herbs, leaves and fruit but are said to also eat meat when it is available.

On their islands, the large reptiles fill a similar ecological niche as that of elephants -they are the main consumers of vegetation, and spread seeds that pass through their digestive tracts.

They also clear pathways and clearings for other animals during their search for food.

4. longest-lived Aldabra

 

Aldabra tortoises can live for more than 100 years, and a particularly long-lived one was said to have lived between 152 and 255 years.

Adwaita was a pet of a high-ranking official in the East India Company before being transferred to the Alipore Zoo in 1875.

Indian authorities said he was at least 152, but some sources say that carbon dating of Adwaita's shell showed he was born in the 1750s.

One Aldabra tortoise at the Singapore Zoo, Astove, is well into his 70s.

5. Gifts of Aldabra tortoises


Astove, an Aldabra tortoise, was a gift from the Seychelles to Singapore in 1989 and lives at the Singapore Zoo. PHOTO: ST FILE

Two Aldabra tortoises - one male and one female - were sent to Singapore from the government of Seychelles in 1989. However, the female died in 1990.

In 1992, two five-year-old females were given to Mr Lee Kuan Yew by the Conservator of Forests in Mauritius when the then Senior Minister visited Mauritius.

6. The difference between male and female tortoises

Dr Cheng Wen-Haur, Chief Life Sciences Officer, Wildlife Reserves Singapore, said that the two new tortoises will be a "great boost" to the zoo's breeding programme.

The slow-growing species reaches sexual maturity only when 20 to 30 years old. The females lay about 25 eggs between February and May, which hatch after four to eight months.

Male tortoises have a concave plastron or lower shell which makes it easier for it to mount the female tortoise for mating.

SOURCES: Singapore Zoo, Smithsonian National Zoological Park, BBC