Thursday, March 12, 2009

Save the tiger

From Vladivostok, Mar 12th 2009

Vladivostok is the core city of Pacific Russian marine forces and was therefore forbidden to foreigners during most of Soviet time. Below the prestigious S-56 now transformed as museum. It contains 7 rooms for 40 people, could transport 12 rockets 7m long each, go 40km/h and up to 24h under water.


But Vladivostok is also more generally an active harbour opened towards Asian neighbours Japan, Korea and China:

And also the entry point to the large Primorski territory and its Sihote Alin mountains, that you can see starting at the back of this cafe:

There is a funny anecdote about this territory. During the Creation of the world, God got tired and falled asleep. Waking up, he noticed that there was a small corner, “Primorie”, remaining without fauna and flora. Gathering all plants and animals he had left, he put them into this lost corner.
This territory is the one of Sihote Alin mountains, sung by Vladimir Arseniev in his roman Dersou Ouzala, who I introduced to you in an earlier post (February 2009). Part of UNESCO human heritage, this region composes one of the largest regions where massifs of ancient coniferous and broad-leaf forests still exist. Besides, the impact of human activities on this region has been very insignificant. A very complicated and bright picture of mutual integration and mixture of different flora and fauna representatives characterize this area. This region maintains the largest number of rare and endangered species, the greater part of which cannot be encountered anywhere else. Almost 1,200 vascular plant species represent the flora of the Sikhote-Alin. This area inhabits 71 mammal and 370 bird species.

Among those numerous animal species present on Primorie territory is the Amur or Siberian tiger that we know from our zoos and circuses, but represents a protected species classified as endangered and scientifically called Panthera Tigris.


The above pictures show the specific Siberian tiger, which differs from other tigers by a paler orange colour and widely spaced brown stripes rather than black. A tiger’s stripes usually act as camouflage within long grass and dense vegetation as they help distort its body outline. However, as the land here is covered in snow for most of the year the Siberian Tiger has developed stripes much paler than that of other tiger subspecies.Siberian tiger also has a white chest and belly and a thick ‘ruff’ of hair around its neck. Specifically designed for the rough climate of Russian taiga, its thicker fur and the layer of fat along its belly and flanks, allow it to live within cold and harsh temperatures which can reach as low as - 46°C.It is the largest of all cats with males growing up to 3.3m long and weighing up to 300kg. The smaller females measure around 2.6m and weigh between 100 and 167kg. They can live up to the age of 25 years in their natural habitat.

Availability of a sufficient prey base is the tiger's major habitat requirement: "wild pigs and deer of various species are the two prey types that make up the bulk of the tiger's diet, and in general tigers require a good population of these species in order to survive and reproduce" (Sunquist and Sunquist, 2002). Based on studies, Karanth et al. (2004) estimate that tigers need to kill 50 large prey animals per year. Tigers are opportunistic predators, however, and their diet includes birds, fish, rodents, insects, amphibians, reptiles in addition to other mammals such as primates and porcupines. Tigers can also take ungulate prey much larger than themselves, including large bovids (water buffalo, gaur, banteng), elephants and rhinos (Nowell and Jackson 1996).
Tigers are generally solitary, with adults maintaining exclusive territories, or home ranges. Adult female home ranges seldom overlap, whereas male ranges typically overlap from 1-3 females, a typical felid pattern of social organization. Tiger home ranges are small where prey is abundant : for example, female home ranges in Chitwan averaged 20 km², while in the Russian Far East they are much larger at 450 km² (Sunquist and Sunquist, 2002). Similarly, reported tiger densities range from 11.65 adult tigers per 100 km² where prey is abundant (India's Nagarhole National Park) to as low as 0.13 to 0.45 per 100 km² where prey is more thinly distributed, as in Russia's Sikhote Alin Mountains (Nowell and Jackson, 1996).

The global tiger population is estimated to range from 3,402 to 5,140 specimens, and is decreasing. In terms of conserving the wild tiger's genetic biodiversity, population biologists prefer to work with a number that approximates the actual breeding population : the number of animals which raise offspring to reproductive adulthood, or effective population size. The number of breeding tigers in one population was equivalent to just 40% of the actual adult population, based on long-term demographic studies in Nepal's Chitwan National Park (Smith and McDougal, 1991). Therefore, the tiger's effective population size could be in the range of 1,361 to 2,056 reproductively successful adults.
More specifically in Russia, a comprehensive winter snow tracking census done in 2005 estimated 331 to 393 adult tigers. Using a similar methodology, 330 to 371 adult tigers were estimated in 1996. Russian Far East represents the largest Tiger Conservation Landscape worldwide with 269,983 km² (to be compared with the smallest : 278 km² in India).

The greatest threats to Tigers are habitat loss, poaching and lack of sufficient prey.

HABITAT LOSS
Once found across Asia, from Turkey to eastern Russia, over the past century Tigers have disappeared from south-west and central Asia, from Java and Bali in Indonesia and from large parts of South-east and East Asia. They have lost 93% of their historic range, and more than 40% of their range in the last decade. Much of the remaining habitat is becoming increasingly fragmented. See below an example of deforestation in Russian taiga.

POACHING
In the early 1990s, trade in Tiger parts was banned worldwide, but Tigers remain in serious danger from illegal wildlife trade —poaching— mainly for their bones for use in traditional Asian medicines, and for their pelts and other body parts, such as teeth, skin and claws, as decorative items. Tiger bone has long been considered to hold anti-inflammatory properties, with some support from Chinese medical research, but many consider the effect to be more psychological than pharmacological (Nowell and Xu, 2007).

I would like to finish on a positive note and share a non-exhaustive list of projects recently launched to help conservation of Tigers :
- In June 2008, the World Bank has announced a global joint venture to help reverse the decline in numbers of Tigers in the wild—the first-ever species initiative by the Bank. To read more: http://www.traffic.org/home/2008/6/9/bank-aims-to-restore-wild-tigers.html
- After a program conducted launched in 2000 for US forests, the American Forests association continues its “Trees for tigers” project to protect the Siberian tiger within its habitat of Russian Far East. Follow: http://www.americanforests.org/planttrees/af_info.php?campaign=tiger
- In February 2009, the Wildlife Conservation Society, together with the World Bank and Global Environment Facility, has announced a commitment of $2.8 million toward tiger conservation across its range. WCS will lead a new project, Tiger Futures, in partnership with other conservation organizations with long-term field experience in tiger conservation throughout countries spanning the big cat’s geographical range in Asia. Article: http://www.sciencedaily.com/releases/2009/02/090227081835.htm

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