Radiated Tortoise

Geochelone radiata

Order: Testudines

Husbandry Information

Housing Requirements

  • Temperature, Humidity, & Lighting:
    • Temperature:
    • Humidity:
    • Lighting: Exposure to natural sunlight or UVB light plays an important role in how the body absorbs and uses calcium. UVB light or natural sunlight allows the tortoise to produce vitamin D3. Vitamin D3 is critical to the tortoise in its ability to absorb and use the available calcium. UVB can be obtained from fluorescent tubes specially made for reptile use or from mercury vapor bulbs, which also provide some heat. If fluorescent tubes are used for UVB, a separate light may be required for heat.
  • Substrate:

Diet Requirements

  • They need a high fiber diet with as much variety as possible. They are grazers and will spend a lot of the time during the day feeding. By planting a wide variety of edible plants in their environment, this will ensure the tortoises to have options for feeding throughout the day.
  • Under human care, they are fed salads.

Veterinary Concerns

  • Respiratory problems may occur when a leopard tortoise gets chilled or is kept in suboptimal conditions. Minor problems may be corrected with increased temperatures. If not corrected, minor problems can progress to more serious conditions such as pneumonia. Signs of a respiratory problem include labored breathing, a nasal discharge, a gaping mouth, puffy eyes, lethargy and a loss of appetite.

Notes on Enrichment & Training

Other

Colony or Breeding Management

Notes species is housed or managed socially or for breeding purposes.

Individual Identification

Dimorphism: There is no size difference between the different genders of radiated tortoises.

Programmatic Information

Transportation

hot water bottle

Temperature Guidelines

  • Brandywine Zoo: During cool weather (under 65°F), supplemental heat is provided with a hot water bottle set to one side of the cooler. Wrap bottle with newspaper for lizards or snakes traveling with the bottle loose, to make cleanups easier in the case of defecation while traveling.

 

Crating:

  • Brandywine Zoo: reptiles travel in a Coleman style coolers that have been amended with extra ventilation holes on the lid (with a wood-burning tool). Small and medium sized snakes travel inside an inside-out, knotted pillowcase. Large snakes travel loose in the cooler that is also bungeed shut. For small and medium lizards and tortoises, the cooler is lined with newspaper.
  • lg cooler sm cooler cooler
  • Brandywine Zoo: Large specimens of this species are transported in a dog kennel.

Tips on Presentation

Touching Techniques

Tips on Handling

 

Potential Messaging

  • In general, animals seen at the zoo do not make good pets. Most have specialized dietary, veterinary, housing, and social needs that are difficult or impossible for even dedicated pet owners to meet. Always ensure that your future pet has not been taken from the wild. Capture of wild animals for the pet trade has significantly damaged the survival prospects of species such as sloths, tamanduas, and many parrots. Captured animals are typically mistreated by profit-motivated traffickers and dealers, resulting in many animal deaths; well-meaning animal lovers may feel like they are rescuing animals by purchasing them but are really perpetuating the cruelty. In addition, many exotic pets are released by their owners when they become too dangerous or demanding, often with devastating effects on local ecosystems. Animals that should never be kept as pets include all bats, primates, and exotic carnivores. Birds, fish, and reptiles have specialized needs, are frequently wild-caught, and damage the local environment if released; guests should be advised to educate themselves and proceed with caution. Domestic dogs and cats are almost always the best option! Many deserving animals are available for adoption at animal shelters. http://www.philadelphiazoo.org/Save-Wildlife/Images/PetWalletBro2012.aspxhttp://pin.primate.wisc.edu/aboutp/pets/index.html
  • One of the best ways for people to help the rainforest is to reduce their use of tropical woods. Many rainforest trees are felled each year for lumber, furniture, and other products that end up in countries all over the world. Much of tropical wood imported into the United States comes from South America, particularly the Amazon Rainforest. Flooring, musical instruments, picture frames and other products made of rosewood should be particularly avoided to slow deforestation on Madagascar and to avoid the extinction of endangered or vulnerable rosewood tree species from forests all around the equator. Ask guests to consider used or vintage furniture or new furniture made of wood that has been reclaimed from old structures. There are many alternatives to conventional lumber including flooring and other products made from fast-growing bamboo, and decking made of recycled plastic formed to look like wooden boards. http://environment.nationalgeographic.com/environment/habitats/rainforest-threats/http://www.globaltrees.org/tp_d_nigra.htmhttp://www.rainforestrelief.org/What_to_Avoid_and_Alternatives/Rainforest_Wood/What_to_Avoid_What_to_Choose/By_Tree_Species/Tropical_Woods/R/Rosewood.html
  • Many regions of Africa including the Congoand the island of Madagascar are extensively mined for coltan and other minerals that go into cell phones, tablets, and computers. Natural habitat, frequently in areas that are legally protected, is lost for wildlife, trees and topsoil scraped away. In addition, toxins from discarded electronics leach out of local landfills and contaminate waterways here at home. Please ask guests to think twice before replacing their electronic devices and to recycle their old ones when they do. http://www.houstonzoo.org/wp-content/uploads/2012/10/Why-should-I-recycle-my-cell-phone.pdf

Acquisition Information

This species is managed by a Green Level SSP.

Studbook Keeper: Stephen Nelson – snelson@zooknoxville.org

SSP Coordinator: Michael Ogle mogle@zooknoxville.org

Comments from the Rating System

Roger Williams Park Zoo: Challenging to present to large groups and transport

Natural History Information

Range and Habitat

Radiated tortoises are found on the extreme southern and southwestern part of the island of Madagascar among the spiny forests and woodlands. They have also been introduced to the nearby islands of Reunion and Mauritius. They live in dry woodlands, scrubs, and thorn bushes.

They have also been introduced to the Island of Reunion.

Physical Description

Around 10-11 inches (plastron measurement) they will reach maturity and will top out between 12-16 inches and a weight of 35 pounds.

This is a typically tortoise-shaped tortoise: they have a high-domed carapace, a blunt head, and elephantine feet. The legs, feed, and head are yellow except for a variable-sized black patch on the top of the head. The carapace is brilliantly marked with beautiful, radiating yellow/white lines contrasting over a jet black shell. Yellow lines radiate from the center of each scute. This is what gives this species their common name. A radiated tortoise has a moderately sized head with a protruding snout and a slightly hooked upper jaw.

Their skin is a dark yellow coloration, with a dark black marking on their blunted head. With elephantine feet, radiated tortoises make for an interesting species for tortoise keepers to care for and maintain.

Life Cycle

The oldest radiated tortoises ever recorded was Tu’i Malila, which died at an estimated age of 188 year old. Typically in captive environments radiated tortoises have shorter life spans, around 60-80 years.

Radiated tortoises are known for being able to lay any month of the year. Radiated tortoises mate in the spring and early summer. They build their nests in March, July, August, or September. 3 to 12 eggs are laid in a pre-excavated hole 6 to 8 inches deep. These eggs must incubate for 5 to 8 months, which is very long for turtles.

Behavior

When caught, this tortoise emits high-pitched cries to startle the predator.

Threats and Conservation Status

This species is endangered and captive breeding is tracked by the North American Studbook.

From the Radiated Tortoise Studbook: This moderately large and attractive species is under threat because of not only its size, but its beauty as well. In 2008, this species was elevated to Critically Endangered status with the IUCN, as surveys have shown drastic population declines throughout its range. This species as well as the spider tortoise (Pyxis arachnoides) was once protected by traditional fady or local taboo. In recent years, the local taboos have subsided, and the tortoises have been collected by the hundreds of thousands in addition to having vanished from approximately 65% of their historic range. Demand for this species for consumption in Madagascar and the black market pet trade in Asia has been primarily to blame for this recent insurgence in their trafficking.

The Turtle Survival Alliance, along with Henry Doorly Zoo’s Madagascar Biodiversity Partnership, Utah’s Hogle Zoo, and Nautilus Ecology are working with the local Malagasy to protect the remaining populations as best as possible.

This species is endangered due to habitat loss, the pet trade, and poaching.
Radiated tortoises originally became endangered because the Chinese settlers of Madagascar used their meat as an aphrodisiac. This species is found in a very restricted range (naturally occurring in an area of less than 20,000 square miles.) No estimates of the wild populations are available, but their numbers are declining, and many authorities see the potential for a rapid decline to extinction in the wild. In the North American studbook, over 300 specimens are listed as participating in captive breeding programs such as the SSP. Captive breeding has shown great promise.

Did you know…

  • Radiated tortoises prefer red-colored food.
  • In Madagascar, this species is known as “sokakes.”

Photographs

Photos: Stephen Nelson

Documents

Any Documents to attach, species spotlights, etc.

Contributors and Citations

  • Houston Zoo, Natural Encounters
  • Brandywine Zoo
  • Philadelphia Zoo
  • Reptiles Magazine
  • Radiated Tortoise Studbook