Determining Minimum Viable Population of Long-tailed Macaque Macaca fascicularis Based on Demographic Parameters : Case study on Lampung Province

Abstract

Determining minimum viable population is a fundamental corestone for conservation biology, but this estimate requires representative demographic parameters. Long-tailed macaque is facing seriously treatened due to high demand for exporting purpose. The need for quota is almost fulfilled from wild harvest and requires from certain age structure and only for male. As impact of this requirement, it will be dangerous for its sustainability in the future. The objectives of the research were to determine minimum viable population, to identify determine variables of minimum viable population and to identify environment factors which influence the minimum viable population. Data of environment factors and demographic parameters were obtained from four different habitat types in Lampung Province. The algebra of Leslie Matrix was used to determine the minimum viable population. The research resulted in the value of minimum viable population varied from each group and its average number was 35 individual consist of 3 male and 6 female of infant, 3 male and 7 female of juvenile, 1 male and 3 female of sub adult, and 3 male and 7 female of adult. The parameter demographic variables which determined the minimum viable population were survival and fecundity. The sensitive analysis and regression showed that survival was the most sensitive variable with the equation was Y = 0,031X1 + 0.518. Multivariate regression analysis was used to identify the environment factors which affected the birth and the death. It showed that the tree density was the most influenced environment variables to birth with equation was Y = 2,478 + 1,56X4 and the death was infleunced by tree density and pole density with the equation was Y = 3,837-2,55X4 -1,93X2