Pairing Behaviours of Silvery Javan Gibbon (Hylobates moloch) in Captivity

• Main Author: SICILIANTY (NIM : 10611039), JANESYA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/22673
• Institution: Institut Teknologi Bandung

The Silvery Javan Gibbon (Hylobates moloch) is classified as endemic and endangered species (IUCN Red List). The population size can be increased through pairing stage as part of ex-situ gibbon conservation program. These research objectives are to analyze social activity pattern and sociosexual (mating) behaviour of new pair Javan Gibbon. Observations were conducted in November and December 2016 from 6.00 am to 4.00 pm using ad libitum and focal pair animal sampling methods. Data were analyzed statistically using pair-samples t test. Daily activity budget of Javan gibbon was also observed as preliminary data. Resting behaviour had the highest percentage (♂65.81%, ♀70.64%), followed by moving (♂14.98%, ♀6.42%), (♂7.96%, ♀8.72%), social behaviours (♂10.63%, ♀10.98%), urination/defecation (♂0.53%, ♀0.64%) ,and alert (♂0.10%, ♀3.15%). There are two times that showed the highest social behavior during the observation in male and female gibbon, which were 10.00 - 11.00 a.m. and 12.00 - 01.00 p.m. There is no difference in social activities between male and female gibbon except calling behaviour. Female had higher time budget for calling behavior than male. Both of them were observed doing interaction that categorized as mating behaviour (i.e. attractivity, proceptivity, and receptivity). Attractivity activity refer stimulus to a mate included genital display behaviour while proceptivity consist of approach, body contact behaviour, play-fighting, and allogrooming. During the study period, there is no receptivity behavior, which usually appeared as copulation behavior. There is no significant differences in mating behavior, especially in attractivity stage (sig.=0.576) and perceptivity stage (sig.=0.290) during observational time. It showed that future investigation needs to observe the mating behaviour in longer time. It also implied that the new pairbond have not been developed and there is no tendency toward copulation behavior after 3 months being paired.