
Panthera tigris (Linnaeus, 1758)
THREATS
Until the 1930s, hunting for sport was probably the main cause for the decline in tiger populations. Between 1940 and the late 1980s, the greatest threat was loss of habitat because of activities such as logging or mineral exploitation.7,14,17. Loss of their natural habitat often leads tigers to move into settled areas in search of food, where they are sometimes destroyed.20 For example, until the mid 1960s tigers were considered "an impediment to agricultural and pastoral progress" and their elimination was actively encouraged in China.22 Habitat destruction may also have an indirect influence on tiger populations through a reduction in the availability of prey.20
In recent years, the illegal hunting of tigers for body parts utilized in traditional Oriental medicines has become a major problem.17 The prosperity of the Southeast Asian and East Asian economies since the 1970s has led to an ever-increasing demand for these medicines. In India, the Wildlife Protection Society of India (WPSI) reported poaching figures indicating about 93 tigers killed in 1994, 115 in 1995, and 40 in 1996. But the Society warns that these figures represent only a fraction of actual poaching activities.15
In Russia the economic crisis combined with a relaxation of border controls and a ready access to the wildlife markets of China, Korea and Japan, led to a dramatic increase in the level of poaching.15,17 In the early 1990s, between 60 and 70 tigers were poached every year. However, the establishment of anti-poaching brigades by the government in 1993 and 1994 with support from several conservation groups, including WWF, has finally paid off. There were fewer than 20 known cases of poaching in 1995 and 1996 respectively.24
The loss of female reproductive potential and the disruption of the complex territorial system of tigers, which leads to low cub survival, means that the impact goes beyond the actual number of tigers killed.16 A further threat is posed by the loss of genetic diversity caused by the reduction of population sizes, and the separation of these populations through habitat fragmentation, which restricts dispersal.13 Studies have shown that loss of genetic diversity within tiger populations leads to decreases in litter size, infant survival and male fertility.12,15,18
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