Dietary The Pattern of Spatial and Temporal Utilization

11

2.5.2. Social System

Javan gibbon has a monogamous and family group system. In one group, usually 1-2 infants can be found. Sometimes sub-adult can be found in a group, but it couldn’t stay longer but later excluded and establish new self-family group. Pregnancy period of javan gibbon is about 197 – 210 days. The elapsed time after one birth to the second is about 3-4 years. Generally, they could live for 35 years.

2.5.3. Distribution

The latest information stated there are only 400 – 2000 javan gibbons left in Java Island; therefore, it has been classified as critically endangered species in 1996 IUCN Red List and listed in Appendix I CITES Eudey and MPSG2000, 2004. It is dispersed and only found in Java, especially in remnant and relatively undisturbed mountain forest. As a top-arboreal, complete brachiated and frugivorous monkey, it needs an evergreen primary forest to live Napier and Napier 1985, Napier and Napier 1967, Kappeler 1981, Kappeler 1984. There are only eight sites that still serve as Javan gibbon’s effective habitat - with large enough population and inter population genetic flow - out of 30 sites that previously identified as their habitats in Java. Five of those sites located in West Java, including Gunung Salak protection forest, Gunung Gede-Pangrango National Park, Gunung Halimun National Park, Ujung Kulon National Park, and Gunung Simpang Nature Reserve Primack et al . 1998.

2.5.4. Dietary

Like the other hylobatids , they eat ripe fruits, bud or young leaves, bud- flower or complete flower and small creatures. Usually these supplies are collected 10 m above the ground Ellefson, 1967; Chivers, 1974; Gittins, 1979 in Kappeler, 1984. According to Prastyono 1999, about 43 species of gibbon’s diet plants is identified from the total of 143 species in Cikaniki, Ciawitali, and Pasir Bivak resort, Gunung Halimun National Park. The life forms habitus of these dietary species were varied from bamboos, lianas and trees. 12

2.5.5. The Pattern of Spatial and Temporal Utilization

Javan gibbon is living arboreal in trees and rarely come down to the ground. According to Tobing 1999, javan gibbon frequently uses the height of about 20 - 25 m above the ground, either in disturbed or undisturbed forest. The utilization of space in 0 – 5 m of height was happened when there was a forest gap which could not trespass through forest canopy. Daily ranging can reach 1500 m. Tobing 1999 reffered to Chivers 1984 and Kappeler 1984 stated that spatial usage type for daily activities is territorial. The size of this territorial area is about 16 ha. They speculated if the destruction happened over their area, small possibility for them to migrate into a new area. The home range or territory area is believed to be defended through calling mechanisms. Alarming bout is conducted by any individual when the intruder could be gibbon from other group, other primates, human, or predators such as leopard, raptors, and so forth came approaching their area. They used about 70.4 of their home range for their territory. The daily range patterns every day was influenced by habitat and floristic season. The family used the middle strata in the forest, a height of between 15-30 m. The top layer height is about 30 m and the lower 0-15 m was rarely used Ladjar, 1996. Elevation is related to the gibbon distribution. Javan gibbon is found below 1600 m asl above sea level Kappeler, 1984. They are rarely found in elevation above 1500 m asl. The ecosystem on that elevation contains a little number food tree species. Moss is very fine available that could obstruct javan gibbon to move. Human pressure is believed to be a barrier or source of disturbance to javan gibbon movement and habitat. Based on Tobing 1999, javan gibbon could detect the human existence in 20 m and then produce an alert behavior. The study of daily activity conducted in Cikaniki, Ciawitali and Pasir Bivak TN Gunung Halimun revealed that the percentages of daily activity were resting 39.1 , feeding 30.3, moving 24.1 and other social activity 6.5 in average Prastyono, 1999. 13

III. METHODOLOGY

3.1. System Development Methodology

The description of system development method is illustrated in thi section, including the brief explanation and information on software and hardware used to develop the system.

3.1.1. System Development

The system, namely SUITSTAT, is developed by using modified iterative- incremental approach. This approach focuses on the developing the functionality of system process-based, not only the activities or management plan to accomplish the system development, such as in the system development life-cycle SDLC or waterfall process Fowler, 2005. The development process has two phases, i.e. initial and construction phase. The scheme of the development method can be seen in the figure below: Figure 1. Iterative and Incremental Approach modified after Barroca et al ., 2000 in Zhao, 2002 Increment 1 Basic Functionality Iteration 1 Iteration 2 Iteration ... Increment 1 Core Functionality Iteration 1 Iteration 2 Iteration ... Increment 2 Add More Functionality Iteration 1 Iteration 2 Iteration ... Increment 3 Complete Functionality Iteration 1 Iteration 2 Iteration ... testing analysis design coding • Requirement Analysis • Habitat Suitability Concept Methodology System Requirement in it ia l Ph a se con st r u ct ion ph a se