Dietary habits of free-ranging banded langur (Presbytis femoralis) in a secondary-human modified forest in Johor, Malaysia

Abstract

Banded langurs, Presbytis femoralis, are distributed in southern Peninsular Malaysia, i.e., Johor and its borders including Singapore. It has been estimated that there are only < 250 mature individuals of P. femoralis in Malaysia and Singapore, and it is currently assessed as Critically Endangered. The dietary information of P. femoralis and even other closely related species has rarely been reported. This study, therefore, aimed to describe their dietary habits and discuss interaction between their feeding behaviour and its surrounding. This study was conducted from February to November 2018, with 15 sampling days each month. We collected a total of 186 sighting hours, using a scan sampling method with 10-min intervals, on a five-langur focal group. We have identified 29 species with 47 items consumed by the banded langur, mostly young leaves (51 %) followed by fruits (45 %), and flowers (3.8 %). The study group spent slightly more time consuming non-cultivated plants but relied on cultivated plants for the fruits. Over 75% of fruit feeding involved consuming cultivar plants; in most cases (73%), they ate only the pule, not the seeds. Since the cultivated plants was planted in human settlement, there is an urgent need to implement conservation measures to untangle the human-langur conflicts for instance, reforestation of a buffer region using non-cultivated plants. There is a potential for building upon our new findings with more detailed investigations, such as more extensive ecological factors influencing the dietary adaptation which would be necessary to support conservation efforts and management decisions of this species.

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.…”

“…The group composition of the Bornean banded langur was investigate using total count method ( Sutherland 2006 ). Following Najmuddin et al (2021) , the counted individuals were classified based on their body size and age-sex characteristics (adult male, adult female, sub-adult, juvenile, and infant), with sub-adults appear smaller than adults. Meanwhile, activity pattern of the Bornean banded langur were observed using scan sampling method within 10 minutes intervals and 5 minutes rest from left to right or clockwise direction to avoid repeated sampling ( Altmann 1974 ).…”

Metabarcoding data analysis revealed the plant dietary variation of long-tailed macaque Macaca fascicularis (Cercopithecidae, Cercopithecinae) living in disturbed habitats in Peninsular Malaysia

“…Habitat quality may also affect dietary diversity ( Mohd-Daut et al 2021 , Mohd-Daut and Md-Zain 2021 ). Primates living in undisturbed forests with greater tree species diversity have more foraging options and are less likely to experience food scarcity than primates living in more fragmented forests ( Poulsen et al 2001 , Najmuddin et al 2019 , Najmuddin et al 2021 ). Intraspecific comparisons of the proportion of plant food resources in different primate groups living in habitats with varying disturbance levels are one technique for investigating how these species respond to human habitat alteration and dietary adjustments ( Wieczkowski 2003 , McLennan et al 2017 ).…”