ECOPHYSIOLOGY OF A WILD NOCTURNAL PRIMATE, THE JAVAN SLOW LORIS (NYCTICEBUS JAVANICUS)

The goal of this dissertation thesis was to bridge the gaps in knowledge and understanding of ecophysiology of a Critically Endangered primate, which can then be applied to conservation management and planning. I studied a population of wild Javan slow lorises (N. javanicus) ranging in a submontane agroforestry habitat in Cipaganti, West Java, Indonesia. I used a cumulative dataset configured of data collected by myself and various other trained members of the Little Fireface Project (LFP) research team between March 2015 and August 2018. Using external bio-logging equipment, I investigated topics of behavioural flexibility and physiological responses to the environment. In Chapter 3, I used skin temperature (Tsk) loggers for measuring the thermoregulation index of slow lorises. Slow lorises displayed sporadic use of daily torpor, with individual variation in torpor depth and minimum Tsk flexibility. In Chapter 4, I monitored and quantified sleeping site selection and its potential role as a thermal refuge for slow lorises as a selective pressure. Bamboo stands buffered ambient temperatures (Ta), providing stable microclimate temperatures for sleeping sites. In Chapter 5, I used accelerometers to examine slow loris sleep patterns and their intrinsic homeostatic sleep need. Sleep-wake patterns of slow lorises anticipated changes in light environment, where they began and ended activity patterns, as well as disruption of naps by changes in Ta. In Chapter 6, I monitored slow loris behaviour to examine how individuals acquire food energy in an anthropogenic habitat. I further monitored the phenology of their food sources to examine how their behavioural ecology role fits into the ecosystem. Slow lorises consumed floral nectars from an introduced leguminous plant Calliandra calothrysus, and contributed to the plant species’ pollinator network in the Cipaganti area. The synthesis of data presented in this thesis suggest that the use of external bio-loggers is suitable (and least invasive) as a proxy method to measure physiology in wild primates. As an important food source that plays a key role in the regular behaviours and physiological responses of Javan slow lorises, C. calothrysus should be considered for conservation re-wilding methods, including: reintroduction of slow lorises to new habitats with presence of C. calothrysus; as well as introduction of C. calothrysus as an ecological substitution to already established Javan slow lorises home ranges. The physiological responses of N. javanicus, particularly to climate and resources, should be considered when choosing translocation and reintroduction sites for rescued slow lorises. The data presented in this thesis overall suggests that N. javanicus is highly adaptable to environmental changes, with a broad scale of thermal flexibility to endure colder temperatures, and the ability to adapt to new food resources in maintaining regular energy intake, while possessing circadian rhythms and activity patterns that are mediated by an intrinsic biological clock, driven by the environment. In regards to evolutionary biology, these data support the hypothesis that heterothermy in primates is an ancestral trait from mainland Africa, before the divergence of lorisids. These data also suggest the sleeping patterns of slow lorises represent phylogenetic inertia for the evolution of human sleep. In conclusion, I suggest that some of our basic notions about physiological responses obtained in the lab may vary in the wild, but can also be applied to rewilding conservation for this critically endangered primate.

Grantor dc:publisher

Oxford Brookes University

Year dc:date

2019

Author dc:creator

• Reinhardt, Kathleen

Contributors dc:contributor

• Nekaris, Anna
• Donati, Giuseppe
• Hernandez-Aguilar, R. Adriana

Statement dc:rights

• All rights reserved

Language dc:language

en

DOI dc:identifier

https://doi.org/10.24384/dah8-4q38

OAI identifier oai:identifier

tle:d7042351-2321-44ad-bfcb-e09d8f91c8e6:d6bd9758-527a-46cd-bfe2-c433766e8fca:1