Relating habitat changes to sustainability of Amur tiger (Panthera tigris altaica)

Background/Question/Methods Rapid change in land use patterns in the vast historical distribution areas of Amur tiger during the past 150 years has been attributed as one of the main driving forces endangering the species. Its current distribution areas have shrunken to the Russian Fareast region and a few scattered patches of nearby China’s Northeastern region where has been also found vegetation deterioration, habitat fragmentation due to rapid development recently. This study is to evaluate the habitat quality, through vegetation type and composition analyses, relating to the sustainability of Amur tiger, and further to examine if the last heaven of Amur tiger is sustainable for preserving the species.  We surveyed ~30 forest plots (representing common forest types in the area) for detailed vegetation composition and traveled for several thousands kilometers for vegetation type survey for remote sensing classification verification. The data were analyzed to examine vegetation changes of typical tiger habitats that indicate the quality through the potential changes of the prey.  The results were used to parameterize the LAPS (Landscape Analysis for Prey Suitability) models for tiger prey simulation.

Results/Conclusions A large tract of primary Korean pine-hardwood forests of the Sihote-Aline mountain area, the core distribution area of the tiger, suffered significant deterioration. The species composition of the forests has changed with large reduction of Korean pine and increase of hardwood species resulting in reduction of energy-rich seed production and increasing energy-diluting leaf production. The direct consequences are the decrease of wild bore population-the major prey of the tiger, and increase of a few ungulate species (such as roe deer) that forced the tiger to shift its prey, reduce the predation success, and lower the carrying capacity of the habitat. The quality of the forest patches in Chinese side was even poorer that hardly support resident tigers though has been improved in the recently years. Although the tiger population in the Russian Fareast region has been maintained constant during the past years, the sustainability of the area for tiger is not optimistic in a long run given the deterioration trend of the large forest area.