Tigers, prey loss and deforestation patterns in Sumatra

A fundamental requirement for conserving a large carnivore such as the tiger is understanding its response to the principal threats of habitat loss and poaching. This thesis investigates the influence of these threats on one of the largest tiger populations on Sumatra, located in the Kerinci Seblat (KS) region, Indonesia.

Interview surveys with a pioneer farming community living adjacent to KS National Park (NP) showed that most farmers had positive attitudes towards tigers and their conservation. Farmers thought that wildlife crop raiding was the greatest limitation to agricultural success and that deforestation would adversely affect tigers, tiger prey and themselves. An analysis of deforestation (forest converted to agriculture) in the KS region between 1995 and 2001 showed a mean deforestation rate of 0.96%/yr. Deforestation was correlated with lower elevations, closer proximity to settlements and public roads, flatter terrain and being outside of KSNP. To mitigate this deforestation, KSNP became the focus of an Integrated Conservation and Development Project (ICDP), but a further analysis showed there was no difference in deforestation rates between ICDP and non-ICDP villages. In villages bordering KSNP, higher rates of conversion occurred in villages with greater occupancy by a logging concession (HPH) and in flatter areas. This suggests that addressing land insecurity created by the designation of customary forest as a HPH was more relevant to lessening deforestation.

In farmland bordering KSNP, most farmers (80.2%) claimed that wild boar were the most destructive crop pests, but this did not corroborate with actual results because although wild boar raided most frequently (76.4%) pig-tailed macaque caused the most damage (73.1%). Investigating the factors that determined tiger prey distribution in the KS region showed a negative association with roads. However, snare trap location was more likely to be found close to logging roads and in richer villages, thereby challenging the rationale of the KSICDP that sought link biodiversity conservation with village development. Tiger distribution was also found to be negatively associated with distance to roads. Using this factor to construct a habitat suitability model identified three subpopulations of 98, 20 and 15 tigers in KSNP. A population viability analysis supported law enforcement activities that kept poaching below 3 tigers/yr in the smaller areas and maintained connectivity with the larger subpopulation.