Food availability, plant diversity, and vegetation structure drive behavioral and ecological variation in Endangered Coimbra‐Filho's titi monkeys

Abstract

There is wide variability in primate behavior and ecology. Understanding how frugivorous primates behave under different habitat fragmentation levels is key for effective conservation and management of species and their habitats. We evaluated the seasonality in activity budget, diet, and ranging behavior of two groups of Endangered Coimbra-Filho's titi monkeys (Callicebus coimbrai). One group inhabited a 14-ha forest fragment, whereas the other lived in a 522-ha fragment. We measured the monthly density of trees and lianas available as food sources over 8 months. We also collected behavioral and group location data every 5 min, from dawn to dusk, using the scan sampling method. The two forest fragments differed seasonally in the number of fruiting food-resource available. In the 14-ha fragment, we found that the time spent by titi monkeys feeding, foraging, resting, and traveling differed seasonally. In the 522-ha fragment, titi monkeys exhibited seasonal differences in time spent sleeping, socializing, foraging, and revisiting food sources. In both titi monkey groups, diets varied seasonally. Our findings indicate that Coimbra-Filho's titi monkeys can exhibit behavioral flexibility in their activity budgets, diets, and movement patterns. Such flexibility is important for this species to survive in fragmented habitats and may be linked to three key factors: speciesspecific resource availability, plant species diversity, and the vegetation structure of each forest fragment.

Human‐induced behavioural changes of global threatened terrestrial mammals

“…In our review, habitat degradation affected the behaviour of mammals with a wide range of body mass, ranging from Chiroptera to Proboscidea (0.01–6100 kg). We found that the effect size for habitat degradation on omnivorous species was the largest, which may be because they are more sensitive to the reduction in food resource availability due to their food habits and seasonal differences in time spent foraging, resting and travelling caused by the seasonal phenology (Souza‐Alves et al, 2021). Hence, we suggest integrating animal foraging ecology principles into landscape design and management, in particular for omnivore species, to maintain their natural resource acquisition and reproduction success in areas where habitat modification is inevitable.…”

“…On the one hand, reduced natural resource availability in fragmented habitats is a major cause of change in animals' foraging time. For example, Coimbra‐Filho's titi monkeys Callicebus coimbrai spent more time foraging in highly fragmented habitats (Souza‐Alves et al, 2021). Altering food availability also led to changes in food selection, such as in bale monkeys Chlorocebus djamdjamensis that spent significantly more time feeding on nonbamboo plants and insects in fragmented forest in response to the relative scarcity of bamboo (Mekonnen et al, 2018).…”

“…Hence, we suggest integrating animal foraging ecology principles into landscape design and management, in particular for omnivore species, to maintain their natural resource acquisition and reproduction success in areas where habitat modification is inevitable. For historically fragmented habitats, improving resource availability such as by restoring vegetation or building ecological corridors may be important measures to ensure animal long‐term survival (Souza‐Alves et al, 2021).…”

“…in time spent foraging, resting and travelling caused by the seasonal phenology(Souza-Alves et al, 2021). Hence, we suggest integrating animal foraging ecology principles into landscape design and management, in particular for omnivore species, to maintain their natural resource acquisition and reproduction success in areas where habitat modification is inevitable.…”

Temperature and exudativory as drivers of the marmoset (Callithrixspp.) daily activity period

“…Studies have proposed that the marmosets' activity period may be shortened systematically during periods of reduced food availability, but this has not been tested (Corrêa, 1995; Ferrari & Lopes, 1990; Ferrari, 1988; Guimarães, 1998). Furthermore, the effect of food availability may be site‐specific (Souza‐Alves, Chagas, Santana, et al, 2021), or even absent in some primates (Fernandez‐Duque, 2003). Only one study investigated systematically the influence of environmental temperatures on the free‐ranging marmoset activity period within its natural distribution (de la Fuente et al, 2014) however, the authors did not control for potentially confounding variables such as food availability and predation risk, and took data at a single site.…”