How does the Colombian squirrel monkey cope with habitat fragmentation? Strategies to survive in small fragments

Habitat loss and fragmentation are the main threats to Neotropical primates. These processes affect the behavior of primate species, changing their feeding and movement patterns. We compared activity budget, daily range, home range and diet of two groups of Colombian squirrel monkeys (Saimiri cassiquiarensis albigena) living in continuous and fragmented areas of Colombia. Additionally, we compared group size, male/female and female/immature ratios from groups in both areas. We collected behavioral data from both groups of S. c. albigena using slow scan sampling every 5 minutes. Additionally, ad libitum group size and composition from other S. c. albigena groups were collected and used for the group size and composition comparison between sites. We found that diet composition varies although percentage of time consuming different food items remains similar for arthropods, fruits and flowers but not for leaves. Leaves were not observed being consumed in the fragmented area. Proportion of time spent consuming each food item was higher for all food items except for young leaves in the fragmented areas compared with the continuous area. Group composition and size were reduced in fragmented areas as well as home range. However, average daily range is higher in fragmented areas. On the other hand, stationary foraging is reduced in fragmented areas compared with the continuous area, while moving and foraging activity increased. Additionally, resting activity is reduced in fragmented areas, while moving increases for the same area when compared with the continuous area. In conclusion, the Colombian squirrel monkey's strategy in fragmented landscapes is to spend more time feeding, increasing the proportion of pioneer species chosen for the diet that are found in forest edges and living fences. Living fences in their home ranges increases the space available for food resources.