Justification:
The Indochinese tiger occurs in Myanmar, Thailand, Lao PDR, Viet Nam and Cambodia (Luo et al. 2004). Its status is poorly known compared to other tiger subspecies. There are no national tiger population estimates for Lao PDR or Thailand. In Lao PDR, the tiger population in the country's second-largest protected area, Nam Et - Phou Louey, was estimated at 7-23 based on low densities (0.2-0.7 per 100 km²) obtained through camera trapping (Johnson et al. 2006). Numbers across the country are likely to be low due to a depleted large ungulate prey base and poaching pressure (Duckworth et al. 1999). Tigers occur in 15 spatially disjunct forest complexes in Thailand (Smith et al. 1999), and were recorded in six out of seven forest complexes where camera trap surveys were carried out (Lynam et al. 2006). The best area for tigers is Huai Kha Khaeng National Park, with an estimated 113 tigers (Simcharoen et al. 2007). Extrapolating the density obtained from Huai Kha Khaeng (3.98 tigers per 100 km²) to the large 18,000 km² Western Forest complex, the largest habitat block for tigers in Thailand, Simcharoen et al. (2007) estimated it could hold 720 tigers, with the potential to harbor 2,000 if prey densities were to increase. However, this estimate should be treated as speculative pending further data from other parts of the Western Forest complex, where conditions are unlikely to be as good as in Huai Kha Khaeng. For example, the distribution map in Thailand's national tiger action plan portrays approximately half of the Western Forest complex population as low density in comparison to the Huai Kha Khaeng population (Tunhikorn et al. 2004). In other Thai forest complexes, including Phu Khieo Wildlife Sanctuary (Lynam et al. 2001) and the Dong Phayayen-Khai Yai complex (Lynam et al. 2006), tigers were few, occurring at much lower densities than would have been predicted on the basis of habitat quali. The national tiger population of Myanmar was estimated at approximately 150, according to extensive surveys covering much of the country (Lynam 2003). Most tigers (approximately 100) are found in the large Hukaung Tiger reserve in the north of the country (Lynam et al. in prep.). Tigers have lost much of their historical range in Myanmar, and where they persist are at very low densities. The other important area for tigers is the forest complex found in northern and southern Taninthayi Division (approx. 50) (Lym 2003). In Cambodia, the estimated population of 11-50 (Chheang et al. 2006) is far lower than originally predicted based on extensive forest cover and relatively abundant prey base (Nowell et al. 1999). In Viet Nam, according to government representatives attending the 2007 International Tiger Symposium of the Global Tiger Forum, a 2004-2005 exercise estimated not more than 100 tigers in areas along the borders with Lao PDR and Cambodia (GTF 2007).
The total population is unlikely to be greater than 2,500. No single subpopulation is likely larger than 250 due to habitat fragmentation, and the population is declining due to habitat loss, poaching, prey base depletion, and human-tiger conflict.
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Decreasing
