Time budget of daily activity of silvery lutung (Trachypithecus cristatus) in coastal forest habitat at Gunung Padang, West Sumatra

Abstract

Primate’s time budgets are the important aspect to investigate their ecological influences in their habitat. This study collected data on daily activities in a group of silvery lutung (Trachypithecus cristatus) in coastal forest habitat at Gunung Padang, West Sumatra, Indonesia from August 2018 – July 2019, using instantaneous scan sampling method with 10-min intervals. This study analyzed the activity of wild silvery lutungs in study site, with emphasis on the age-sex differences and montly changes in their activity budget. This group spent most of time resting in their daily activity (average 47.50% of the total daytime resting), then followed by moving, feeding, grooming and other activities (conflict, nursing, urinating-defecating, playing, etc.). Resting peaked simultaneously in the morning and peaked back in the afternoon while moving and feeding decreased in this period. Their time budgets showed significant monthly variation: they spent a higher value of time feeding from September - Oktober 2018. They also differed among different sex-age classes: nursing females spent more time for actively moving, whereas adult male and single females devoted more time to resting, feeding, and grooming. These differences in their time budgets may reflect fundamental differences in reproductive biology, parental investment and development among the different age-sex classes.

Preliminary assessment of group composition and activity pattern of the critically endangered Bornean Banded Langur Presbytis chrysomelas chrysomelas in Tanjung Datu National Park

“…The activity pattern of the Bornean banded langur indicates that a significant portion of their daily activities is allocated to resting. This finding aligns with similar observations made in other colobine species, including Banded langur ( P. femoralis ) ( Najmuddin et al 2021 ), red langur ( P. rubicunda ) ( Ehlers Smith et al 2013 ), Mentawai langur ( P. potenziani ) ( Hadi 2011 ), proboscis monkey ( N. larvatus ) ( Matsuda et al 2009 ), and silvered langur ( T. cristatus ) ( Akbar et al 2021 ). The Bornean banded langur were often seen resting in position where they sat in a hunched position (Fig.…”

“…Compared to other studies ( Matsuda et al 2009 , Ehlers Smith et al 2013 , Abdul-Latiff et al 2019 , Siti-Kauthar et al 2019 , Najmuddin et al 2020 , Akbar et al 2021 , Santoso et al 2023 ) social activities such as grooming, mating, playing, and agonistic were not recorded in this study. It might be due to several factors, including the dense forest canopy at the study site, which limit observers vision and make it difficult to observe primate behaviours.…”

“…Comparatively, the Bornean banded langur spend more time feeding (26%) than other closely related species such as P. femoralis , which allocate 21% of their time to feeding ( Abdul-Latiff et al 2019 ), 12.1% for T. cristatus ( Akbar et al 2021 ) and 12.6 % for T. obscurus ( Siti-Kauthar et al 2019 ). The diet of langur in this survey consisted mostly of leaves (81%) such as Resak Laru ( Vatica pauciflora ) and Mengkudu Besar ( Morinda citrifolia ) and 19% of fruits, notably Kerueh ( Lophopetalum pallidum ).…”

Social Behaviour of Endangered Macaque Species at Kalisalak Forest, Central Java-Indonesia

“…SF and female parents or adults mainly do grooming with other group members. AF is often seen grooming their infants, one of the parental care ways [64]. Grooming of the Infant was purposed to IOP Publishing doi:10.1088/1755-1315/1220/1/012021 6 remain clean from dirt [65,66].…”

“…The infant is not agonistic because its mother still guards it. The mother would avoid looking for a safe place if there were a fight [64]. Female parents also often perform agonistically with other individuals with lower hierarchies.…”