I. Introduction
a. Conservation status
The Asian Giant Tortoise, scientifically known as Manouria emys, is among the largest tortoise species found in Asia. This species is native to Southeast Asia, particularly found in the rainforests of Thailand, Malaysia, Indonesia, and parts of Myanmar. They inhabit a range of environments, including lowland and hill forests. The Asian Giant Tortoise is listed as “Critically Endangered (CR)” on the IUCN Red List of Threatened Species (2023). This status indicates that the species faces a very high risk of extinction in the wild. Most of the tortoises species, including the Asian Giant Tortoises are abandoned species. It means that this species lack of sufficient attention and resources to protect the species.
b. The role in ecosystem
Tortoises, in general, can be indicator species, meaning their health reflects the overall health of their ecosystem. Changes in their population and health can indicate changes in environmental conditions, such as habitat degradation, pollution, or climate change. Asian Giant Tortoises are herbivores, feeding on a variety of vegetation including fruits, leaves, and stems. By consuming fruits, they play a crucial role in seed dispersal. By feeding on vegetation, Asian Giant Tortoises help in controlling plant growth and maintaining a balance in the forest understorey. Their movement and foraging behaviour can also aid in soil aeration and nutrient distribution, which is beneficial for plant growth.
c. The population threats
The loss of habitat due to deforestation for agriculture, local settlement, logging, and the development of infrastructure is one of the most significant threats. As their habitat shrinks and becomes fragmented, tortoises lose the space and resources they need to survive and reproduce. Asian Giant Tortoises are often caught and sold illegally in the pet trade. Their shells are also valued in traditional medicine and as ornaments, which contributes to their overexploitation. In some regions such as in Bengkulu or North Kalimantan, these tortoises are poached for their meat, which is considered a delicacy. In addition, Asian Giant Tortoise have a low reproductive rate, with females laying a small number of eggs each year. The combination of low birth rates and high mortality from the threats mentioned above leads to a decline in population.
II. Understanding the Asian Giant Tortoise
a. Morphology characteristics
The Asian Giant Tortoise exhibits distinctive morphological features that make it unique among tortoises. As one of the largest tortoise species in Asia, adults can reach significant sizes. They typically weigh between 20 to 80 kilograms, and their carapace (shell) can measure up to 60 centimetres in length, although there are reports of individuals growing larger. The carapace is elongated and domed, but not as high-domed as some other tortoise species. It’s typically a dark brown or black colour, with a rough texture and prominent growth rings on each scute. The plastron is also dark and can have lighter areas. It is hinged, allowing the tortoise to retract its head and limbs for protection. The head is relatively small compared to the body size and is also dark in colour. It has strong jaws for crushing and grinding plant material. The tail is short and stubby, more pronounced in males than females. Males are generally larger than females and have a concave plastron, which assists in mating. They have well-developed senses, including good eyesight and a keen sense of smell, which are important for finding food and navigating their environment.
b. Habitat of Asian Giant Tortoise
Their preferred habitats are tropical and subtropical moist broadleaf forests. They can be found in both primary and secondary forests, which means they are adaptable to a range of forested environments, provided there is adequate vegetation cover and humidity. The Asian Giant Tortoise typically occupies lowland and hilly areas, often in regions that are undisturbed by human activities. They can be found at various elevations, from sea level up to about 1,000 meters (approximately 3,280 feet). The climate within their habitat is generally warm and humid, which is typical of equatorial rainforests. These conditions are crucial for their thermoregulation and hydration. Dense vegetation is a key aspect of their habitat, providing both food and shelter. They are herbivorous and consume a wide range of plants, including leaves, fruits, and flowers. The rich plant diversity of their habitat supports their varied diet. They require access to standing or slow-moving water bodies for hydration. They may also use mud wallows, which are important for thermoregulation and possibly for protection against parasites.
c. Behaviours
These tortoises are primarily herbivorous and spend a significant amount of time foraging for food. Their diet consists of leaves, fruits, flowers, and other plant materials. They are known to forage along well-worn paths and have specific feeding areas. Asian Giant Tortoises sometimes create shallow burrows or depressions in the forest floor. This behaviour helps them regulate their body temperature and may provide some protection from predators. Being ectothermic (cold-blooded), these tortoises rely on external heat sources to regulate their body temperature. They bask in the sun to warm up and may use mud wallows to cool down or to avoid overheating. The mating behaviour of Asian Giant Tortoises can be quite aggressive. Males may fight for access to females, often resulting in loud vocalizations and physical confrontations. Females lay eggs in nests dug into the ground, and they may guard the nests for a short period after laying. While not highly territorial, males can exhibit territorial behaviours during the breeding season, defending areas where receptive females are present. Asian Giant Tortoises are generally solitary animals, coming together primarily for the purposes of mating. However, they may occasionally be seen in small groups, especially in areas with abundant food resources. When threatened, these tortoises will retract their limbs and head into their shells for protection. Their hard shells provide an excellent defense against most natural predators.
III. Threats to Asian Giant Tortoise Survival
a. Habitat Destruction and Fragmentation
Habitat destruction and fragmentation pose significant threats to the Asian Giant Tortoise. Tortoises rely on a variety of plants for food. When forests are cleared or degraded, the diversity and abundance of these food sources can be severely reduced, leading to malnutrition or starvation. Female Asian Giant Tortoises require specific conditions to lay their eggs, such as soft soil and appropriate humidity. Habitat destruction can remove these critical nesting sites, which are necessary for the successful reproduction and survival of hatchlings. Destruction of the natural forest cover can expose tortoises to predators. Without the dense underbrush or fallen leaves to hide in, young and adult tortoises become more vulnerable to predation. The microclimate within undisturbed forests is typically humid and stable, conditions that tortoises need for thermoregulation. Deforestation can lead to drier, hotter conditions that are unsuitable for the tortoises and can affect their health and ability to reproduce. When a continuous habitat is broken into smaller, isolated patches, tortoises may find it difficult to find mates, leading to a decrease in genetic diversity and an increased likelihood of inbreeding. Fragmentation can also prevent movement between patches. As their habitat becomes fragmented, tortoises may wander into agricultural areas or settlements in search of food, where they can come into conflict with humans. They may be become targets for poaching. Roads, buildings, and other structures can create physical barriers to tortoise movement, leading to isolated populations. Such barriers can prevent access to essential resources like food and water and can also be direct threats.
b. Illegal Wildlife Trade and Poaching
Wildlife trade for pets and poaching represent significant threats to the Asian Giant Tortoise. These tortoises are often poached for the illegal pet trade due to their size, longevity, and unique appearance. The high demand can lead to overharvesting, which significantly reduces their populations in the wild. Because tortoises generally have low reproductive rates, they cannot replenish their numbers quickly, making them particularly vulnerable to overexploitation. Poaching disrupts the natural population dynamics of tortoises. The removal of a large number of individuals, particularly breeding adults, can have a substantial impact on the population’s ability to sustain itself. This can lead to a decline in population size and genetic diversity, which in turn affects the species’ resilience to environmental changes and other threats. For many people living in proximity to the Asian Giant Tortoise’s habitat, poaching can represent a significant economic opportunity. The lack of alternative livelihoods can make it difficult to deter poaching without offering sustainable economic alternatives. In many regions where the Asian Giant Tortoise is found, wildlife laws may either be insufficient or not effectively enforced, making it easier for poachers and traders to operate.
c. Climate change and Its Impact on Habitat and Food Sources
Being ectothermic (relying on external sources of body heat), tortoises such as the Asian Giant Tortoise are sensitive to changes in environmental temperatures. Climate change can lead to temperature extremes that may exceed the tortoises’ threshold for heat tolerance, potentially causing heat stress and even death. As global temperatures rise, the natural habitats of the Asian Giant Tortoise may change. Rainfall patterns can shift, leading to drier conditions in some areas and excessive moisture in others. These changes can alter the types and distributions of vegetation the tortoises rely on for food and shelter. The sex of tortoise offspring is often determined by the incubation temperature of the eggs. Climate change could skew sex ratios if temperatures rise or fall beyond the narrow range required for balanced sex determination, potentially leading to population declines. Climate change could force tortoises to alter their behaviours, such as the timing of feeding, mating, and nesting. If these behavioural changes do not align well with the environment or the availability of resources, the tortoises’ survival could be compromised. Changes in climate can lead to shifts in the types and availability of vegetation. If the plants that tortoises depend on for food become scarce or their nutritional quality changes, tortoises could suffer from malnutrition or starvation.
d. Predation and Competition from Domestication Animals
The most vulnerable stages in the life cycle of tortoises are the eggs and juvenile stages. Predators, which can include mammals, birds, and other reptiles, often seek out and prey on tortoise eggs and juveniles. In their native habitats, tortoises have evolved with a certain set of predators and have developed strategies to cope with them. However, when new predators are introduced, especially due to human actions, the tortoises may not have effective defenses against them. Buffaloes and cows are large herbivores that consume significant amounts of vegetation. In areas where their grazing overlaps with tortoise habitats, they can deplete the vegetation, leaving less food available for the tortoises. The grazing and trampling by large domesticated animals can lead to soil compaction, which can affect the growth of vegetation and make the soil less suitable for tortoise nesting. The alteration of the landscape caused by overgrazing can also make the habitat less suitable for the tortoises. Domestic animals can be carriers of diseases or parasites that are transmissible to wildlife, including tortoises. The introduction of these diseases into wild populations can have significant health impacts, particularly if the tortoises have no natural immunity against these illnesses. Domestic animals often congregate around water sources, which can lead to the contamination of these areas through waste products. Contaminated water sources can be detrimental to the health of tortoises and other wildlife.
IV. Current Conservation Efforts
a. Global and Local Conservation Initiatives
Up to now, projects or activities related to the conservation of the Asian Giant Tortoise in Indonesia have never been conducted. In fact, there have been very few conservation efforts undertaken in the countries that are habitats for this species. Conservation projects for the Asian Giant Tortoise that have been undertaken in other countries include:
- Captive Breeding and Reintroduction in Bangladesh. A project led by the Creative Conservation Alliance, in partnership with the Turtle Survival Alliance, Bangladesh Forest Department, Prokriti O Jibon Foundation, Future for Nature, and IUCN Tortoise and Freshwater Turtle Specialist Group.
- Reintroduction of the Species in Bangladesh. Ten captive-bred Asian Giant tortoises were released into the Chattogram Hill Tracts of Bangladesh.
- Collaboration with Local Communities. The involvement of local communities, particularly in the Chattogram Hill Tracts to conserve the Asian Giant Tortoise.
- Reintroduction of the Species in India. ten captive-bred juvenile Asian Giant Tortoises were released into a protected forest (Nagaland, Northeast India).
b. Governmental Policies and Laws
In Indonesia, the protection of the Asian Giant Tortoise, is governed by Government Regulation Number 7 of 1999 on the Preservation of Plant and Animal Species. This regulation classifies the Asian Giant Tortoise as protected animal. However, CITES has included the Asian Giant Tortoise in Appendix II category. Appendix II of CITES includes species that are not necessarily currently threatened with extinction but may become so unless trade is closely controlled. International trade in specimens of Appendix II species may be authorized by the granting of an export permit or re-export certificate. Although international trade is still permitted, the Asian Giant Tortoise is fully protected by regulations in Indonesia, so international trade of the Asian Giant Tortoise from the wild is not allowed (Based on Law No. 5 of 1990).
c. Role of Wildlife Conservation Organizations and NGOs
The relatively limited role of NGOs in protecting the Asian Giant Tortoise in Indonesia can be attributed to several factors. There may be a lack of awareness and funding, as resources are often allocated to species that attract more public and media attention. Donors and the public may be more inclined to support species with higher visibility and perceived importance. Tortoises lack the charismatic appeal that larger, more iconic animals like tigers or elephants have, which can draw more public and donor interest. NGOs may prioritize their resources for species that are under greater threat, have a greater ecological impact, or where conservation efforts are more likely to succeed. Additionally, there might be a shortage of professionals with the specialized knowledge required to care for and manage tortoise conservation programs.
d. A Success Story in Tortoise Conservation.
Conservation efforts for the Asian Giant Tortoise should reflect on the success of conservation efforts made by the government and NGOs in saving the Rote Island Snake-necked Turtle (Chelodina mccordi), which has been declared extinct in its habitat, but can still be found in ex-situ breeding (zoos). The Rote Island Snake-necked Turtle (Chelodina mccordi), recognized as one of the world’s 25 rarest turtles, has been the focus of significant conservation efforts. East Nusa Tenggara took a commendable step by establishing the Rote Essential Ecosystem Areas in June 2019 to protect and potentially reintroduce this species. This designation is aimed at protecting the last feasible habitats of the turtle, which include three lakes on Rote Island: Peto, Lendoen, and Ledulu. The conservation measures also include captive breeding, assurance colonies, genetic management, reintroduction efforts, and field surveys. This initiative signifies an important milestone for the protection of The Rote Island Snake-necked Turtle and underlines the regional government’s commitment to protecting the species and its natural habitat.
V. The Role of Communities
Community involvement is crucial in the conservation of the Asian Giant Tortoise. Communities can be educated about the importance of the Asian Giant Tortoise and the threats it faces. Local communities can be trained to monitor tortoise populations and their habitats. This includes tracking their numbers, health, and reporting any illegal activities like poaching or habitat destruction. Community members can participate in habitat restoration efforts, such as planting native vegetation, removing invasive species, and creating local protected areas under local regulation (such as Village Regulation/Peraturan Desa) that provide safe environments for the tortoises. Additionally, communities can work with conservation organizations to develop and implement strategies for the protection and conservation of the Asian Giant Tortoise. Establishing community patrols to guard against poaching and illegal trade can be an effective measure to protect tortoises. Local communities can also support scientific research by providing local knowledge, assisting in field surveys, and participating in conservation projects.
VI. Conclusion
The Asian Giant Tortoise is an integral part of the ecosystems in which it lives. Its survival contributes to the maintenance of a balanced and diverse ecosystem. Biodiversity is crucial for ecosystem health, resilience, and functionality. the Asian Giant Tortoise plays a significant ecological role. It may contribute to seed dispersal and nutrient cycling within its habitat. The Asian Giant Tortoise can serve as an indicator of the health of its environment. Endangered species often signal broader environmental problems, such as habitat degradation, climate change, or pollution, which can affect many other species, including humans. Each species, including the Asian Giant Tortoise, is a unique genetic resource. Losing a species means losing a wealth of genetic information that could have potential scientific, medical, or agricultural value. The study of the Asian Giant Tortoise can provide valuable insights into evolutionary biology, conservation science, and environmental studies. humans have a moral and ethical responsibility to protect other species from extinction, particularly when human activities have directly contributed to their endangered status. Eventually, humans have a moral and ethical responsibility to protect other species from extinction, particularly when human activities have directly contributed to their endangered status.
