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chapter 2 Conservation of Mega-Cats: Problems and Approach G Umapathy key concepts Mammalian Diversity Carnivores Mega-cats in India Threats Approach Conservation of Mega-Cats: Problems and Approach ö 9 MEGA-CATS IN INDIA All cats belong to the Feline family, and have typical characteristics such as agility, excellent sight and hearing. This family includes the fastest land animal cheetah. All of them, except cheetah, have retractable claws, and almost all of them lead a solitary life with the exception of lions. The Indian felids consist of 14 species. Most of them are widely distributed, except the Asiatic lion, which has restricted distribution. Among the mega-cats, the tiger, the Asiatic lion, cheetah, leopard, snow leopard and clouded leopard are considered to be the major ones. However, these species are facing serious threat to their survival in the wild due to poaching and habitat destruction. Status and distribution of some of the major mega-cats is described below (Fig. 2.1). The tiger: Tiger is Indias national emblem and was used as an official seal during the Indus valley civilization (Year 2500 B.C). Over the past century it has FIG. 2.1 Distribution of some mega-cats in India 10 ö You Deserve, We Conserve spread widely all across the Asian continent including Sumatra, Java and Bali. The fossil-remains of the tiger were discovered in the New Siberian Islands. It is well adapted to the wide variety of habitats ranging from tropical rainforests and mangrove-swamps to grasslands and rocky terrain. Of the eight sub-species of tiger, three species, namely, the Caspian tiger (Panthera tigris virgata), the Bali tiger (Panthera tigris balica), and the Javan tiger (Panthera tigris sonadaica) are considered to be extinct and the remaining five species, namely, the Indian tiger (Panthera tigris tigris), South China tiger (Panthera tigris amoyensis), the Siberian tiger (Panthera tigris altaica), Indochinese tiger (Panthera tigris corbetti), and the Sumatran tiger (Panthera tigris sumatrane) are considered endangered. All these sub-species are facing serious threat to their survival due to habitat fragmentation, habitat loss and poaching for illegal trade of body parts. In 1900, tiger population in India was about 40,000, but it has now declined to 3700 to 4000 individuals in the wild and thus considered as critically endangered species. At this rate of decline it is feared that tigers will face further depletion in their population and would be extinct by 2025. The Asiatic lion: Lion is a symbol of power and strength and has been associated with Emperor Asoka (Sarnath Pillar) since 2000 years ago. It is a very social animal and lives in groups called prides. Asiatic lions are genetically different from African lions, however the difference is less than that of differences among human races. The morphological differences in Asiatic lion include a longitudinal fold of skin running along the belly, shorter hair around the neck (mane) and visible ears. The size of the body is slightly smaller than African lions. In the past centuries, the Asiatic lion was found throughout northwestern Asia including Iraq, Palestine and northern India. Habitat loss due to agriculture, human population pressure and hunting, has now restricted the lions to only Gir forests of Gujarat and they are not found elsewhere in India. In 1900, their population was reduced to mere 20 individuals in Gir forests, but as a result of effective measures by the Government of India for their conservation, this number increased to 374 individuals in 2002 (as a single population). These small and single populations are more vulnerable to extinction due to an epidemic or any natural calamities like fire, flood, etc.; therefore, there is an urgent need for an effective conservation plan. This plan should necessarily include maintaining a healthy captive population and finding out a second home for the Asiatic lion as proposed by Government of India in Kunu sanctuary, Madhya Pradesh (MoEF, 2001). The Asiatic cheetah: The Asiatic cheetah once widely distributed throughout middle-east Asia including northern India and extending northwards into former USSR, is now restricted to only Iran and few parts adjacent to Pakistan, Afghanistan and Turkmenistan. The other subspecies occur in south-western Sahara in Africa with a population of about 10,000 to 15,000 individuals. In India, it was last sighted in 1950s, and has now become extinct. In Iran about 50 to 100 individuals occur in the wild with highly fragmented populations. The major reasons for the decline of cheetah population are reduction of prey-base, especially the antelope, due to over grazing by livestock and hunting as well as persecution by human beings (Divyabhanusinh, 1995). Conservation of Mega-Cats: Problems and Approach ö 11 The snow leopard: This species is found in the high altitude mountain ranges of northern India, Nepal, Bhutan, Mongolia, China, Central Asia, Afghanistan, Pakistan and the former USSR. The present world population is about 5000 to 6000 individuals; and in India, it is estimated to be around 500. Poaching, decline of natural prey, and encroachment of alpine pastures by human and livestock are the major causes for the decline of this species. The leopard: It is one of the widely distributed mega-cats of India. The current ranges include Arabia, Asia Minor to south Turkmenistan, south-east Uzbekistan, south-west Tadzhikistan, Iran to Baluchistan, Sind and Kashmir, Nepal to Assam, south to Cape Comorin, Sri Lanka, south-west through Burma (Myanmar) to Malayan Peninsula, Java and Thailand, Indo-China to China, Tibet, Manchuria to Korea, and above 50° latitude in eastern Siberia. It is a very adaptable species and survives in all environmental conditions ranging from a cold desert to a tropical rainforest. However, this is also facing serious threats from poaching for wildlife trade purposes and killing by human beings. THREATS Habitat Loss and Poaching The major threat to biodiversity is habitat loss and degradation, affecting 89% of all threatened birds, 83% of mammals and 91% of all threatened plants assessed globally. Most of the wild cats populations are declining due to habitat loss and degradation. The major reason for habitat loss and degradation are expansion of agricultural lands and industrial development. As human settlements and agriculture expand, the prey becomes scarcer and this forces the cats to kill many livestock in the protected as well as unprotected forests, and in turn angry farmers kill the cats by poisoning. Recently, poaching has emerged as a serious threat to the survival of the mega-cats in the wild; it has become the primary reason for the decline of many a populations in several places. Illegal demand for tiger parts for use in medicine in south and south-east Asia and international trade in tiger skins are main reasons for poaching of Indian tigers. In 2001, about 72 tigers were reportedly killed in India for the above-mentioned purposes. Inbreeding Depression When populations become small and are isolated for several generations, they are forced to breed with close relatives. This leads to depression in the fitness for survivalthe phenomenon, which is termed as inbreeding depression. The consequence of inbreeding depression is decrease in fertility, high juvenile mortality and birth defects. For example, in African cheetahs, high mortality in 12 ö You Deserve, We Conserve juvenile and very low sperm count with high incidence of abnormal sperm have been observed. Inbreeding also leads to the expression of specific genetic defects that are not expressed due to dominant normal alleles in outbred population. A high incidence of a genetic defect in the diaphragm of critically endangered Golden lion tamarins, and kinked tail and cryptorchidism in the Florida panthers, are examples of such defects (Mansfield and Land, 2002). However, some species have low genetic heterozygosity despite the absence of any population decline; for example, carnivores, especially, the northern elephant seal have low variability (Weber et al. 2000). Loss of Genetic Variability Habitat fragmentation leads to population fragmentation and isolation of small populations. These small isolated populations are more prone to environment and demographic stochasity and consequently are known to lose genetic variability, ultimately suffering from inbreeding depression and homozygosity. This is illustrated by the African cheetahs, which are genetically extremely uniform, thereby making them more susceptible to diseases, infertility and high infant mortality (OBrien et al. 1985). APPROACH Maintaining viable healthy population of species, whether plant or animal, is a crucial factor in biodiversity conservation. The conservation measures include both: 1) in situ conservation, where animals and their original habitats are protected from further degradation, poaching, etc., and 2) ex situ conservation, where animals are brought into captivity (zoos, aquaria, etc.) and bred for rehabilitation to the original habitats. The conservation and management of big cats has to be treated as integral ecosystem conservation as a whole. The survival of the top predators is based on the population of herbivores, which in turn depends on the complex structure of forests and soil conditions making up an ecosystem. In other words, conservation and management of individual species such as tigers, lions and leopards, etc. are equivalent to the conservation of the whole ecosystem of a particular area. In an attempt to conserve Indian wildlife, Government of India initiated many conservation programmes, namely, Project tiger, Project elephant, Project hungul, Project crocodile breeding, etc. In 1973, Government of India initiated Project tiger as an ecosystem-based approach and declared 15 tiger-reserves in different habitats across the country, for the protection of prey-species and rehabilitation of degraded habitats. Other conservation efforts include the establishment of many Biosphere Reserves, National Parks, Sanctuaries, Reserve forests and other Protected Areas. 14 ö You Deserve, We Conserve left, this has been tried now in many domesticated species.