Forests of the Russian Far East (RFE) are a biodiversity hotspot rich in endemic and rare species and the only known habitat for the critically endangered Amur tiger (Panthera tigris altaica). Low prey densities found even in the best quality habitats in the RFE necessitate ~ 500 km2 tiger home ranges, thus requiring availability of large contiguous sections of forested habitat to support the minimum viable population of the species. With the projected increase in fire danger over Northern Eurasia the rates of habitat conversion in the RFE are likely to be amplified by wildland fire. Fire events are expected to increase in extent, frequency, and severity leading to an abrupt conversion of forests to open landscapes and minimizing habitat availability and connectivity. In this study the Fire Threat Model (FTM) is parameterized to assess the impact of wildland fire on the Amur tiger and its habitat. The remotely sensed data-driven FTM is applied to analyze fire threat to the tiger meta-population based on the patterns observed during 2005 – 2007. The model’s predictive capability is used further to evaluate potential long-term changes in fire threat under the future scenarios of climate change produced by the ECHAM5 General Circulation Model.
The results show that at present in low to moderate fire years the Amur tiger habitat is rarely threatened by wildland fire. The combination of low fire activity with trajectories of vegetation recovery within the existing tiger habitat results in overall low (0.3 on the 0 – 1 scale) fire threat throughout the year. Only relatively small and localized high fire threat occurrences were observed in the RFE during 2005 - 2007. The range of potential change in fire threat by the end of the 21st century, as projected by various climate change scenarios of the Special Report on Emissions Scenarios (SRES), is considerable. Under the most favorable SRES B1 scenario fire threat is likely to remain at the current low levels. However, under the most unfavorable SRES A2 scenario fire threat to the Amur tiger and its habitat will be up to 20% higher. The magnitude of change will vary in space and time with the most pronounced increase in the southern portion of the known Amur tiger habitat. Fire threat is expected to rise up to 40% throughout late summer and fall, however, the frequency of episodic high fire threat events is likely to increase throughout the year.