Temperature influence on ecology and behavior of Callicebus nigrifrons (Primates: Pithecilidae)

Author(s)

Carla Cristina Gestich

• Document type: Master's Dissertation
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia
• Defense date: 2012-03-20

Examining board members

Eleonore Zulnara Freire Setz; Júlio César Bicca Marques; Cristiana Saddy Martins

• Advisor: Eleonore Zulnara Freire Setz

Abstract

Variations in ambient temperature can change the energy requirements of endothermics due to costs of thermoregulation. So, ambient temperature can influence animal's behavior. The aim of this work was to investigate ambient temperature influence on wild black-fronted titi monkeys (Callicebus nigrifrons) behavior. We conducted this study in Serra do Japi, region with marked seasonality and temperature reduced due to high altitude. We analyzed the relation between temperature and the following variables: activity pattern, types of food consumed and thermoregulatory behaviors observed during resting (microhabitat selection, contact between individuals and body posture). In lower night minimum temperatures, which may represent thermal stress to titi monkey, they started their activities later in the day, after ambient temperature increase. There was no correlation between path length and ambient temperature, but titis moved more at beginning of the day (at the coldest hours), when they were starting these activities. During the coldest months, titis moved less, which could be a strategy to save energy. During this period, they did not select higher-calorie food items, but there was an increase in foraging behavior (not related to fruit availability), which is consistent with the idea that the energy costs of thermoregulation can influence food intake. The sunny resting places were selected at low temperatures. This behavior could be used to reduce thermoregulation costs, allowing the increase of heat absorption from solar radiation. The contact between individuals throughout the day was not related to the temperature and may be influenced only by social interactions. Body postures were not influenced by ambient temperature and postures that avoid heat loss were predominantly adopted. This is probably due to the small size of the species (considering the high surface/volume ratio) which contributes to greater heat loss at low temperatures. We concluded that titi monkey's behaviors vary in function of ambient temperature, such as microhabitat choice and pattern of moving and foraging (AU)

• FAPESP's process: 10/04034-9 - Thermoregulation influence on ecology and behavior from Callicebus nigrifrons (Primates: Pitheciidae)
• Grantee: Carla Cristina Gestich
• Support Opportunities: Scholarships in Brazil - Master