Visitor effect on the behavior of a group of spider monkeys (Ateles geoffroyi) maintained at an island in Lake Catemaco, Veracruz/Mexico

Abstract

We analyzed the effect of human visitors on the behavior of a group of spider monkeys (Ateles geoffroyi) kept on a small tourist island. Although the spider monkey is a common species in zoos, there are very few specific studies on visitor effects on these monkeys. We conducted behavioral observations on the group of spider monkeys to evaluate the effect of visitors. We also used actimetry devices to measure the variations in the spider monkeys' locomotor activity associated with human presence. With regard to the effect on behavior, we found an increase in self-directed behaviors and a decrease in vocalization, both associated with human presence. Moreover, our results suggest that when people feed monkeys, there is an increase in agonistic behaviors. On the other hand, we found that changes in activity levels in response to human presence vary among individuals. We conclude that changes in spider monkeys' behavior could provide evidence of the negative effect of visitors in our study conditions. Although we discuss the differences in activity levels due to differences in social position, further research is required this topic. Our results can be used to inform management plans for this species in captivity. Improving this relationship between humans and non-human primates through tourism education programs would benefit ecotourism and therefore species conservation programs.

Diel and infradian (7‐day) activity rhythms in Mexican spider monkeys (Ateles geoffroyi) kept with and without visitor contact

“…Therefore, it seems reasonable to suggest that the tourist boats visiting Tanaxpillo Island may be stressors for the monkeys kept there. In agreement with that, Pérez‐Galicia et al () observed that the tourist activity around the island elicited increased agonistic behavior between group members. The deviating activity patterns found in a previous study in spider monkeys kept in a large wire mesh cage situated in the more frequently visited entrance area of the Pipiapan primate centre (Muñoz‐Delgado et al, ) may also be explained as a consequence of stress induced by human activities.…”

“…Since this is the only—or at least the most obvious—factor with a corresponding 7‐day rhythm in these monkeys’ environment, it seems reasonable to assume that their weekly activity peak was induced by the marked increase (up to 3‐fold) in tourist activity on Saturday and Sunday. Pérez‐Galicia et al () also observed that the number of human visitors per boat taken to the island had no (further) effect on the observed changes in some behavioral activities such as vocalization, self‐directed, and/or agonistic behaviors. Hence, we suggest that the crucial environmental factor eliciting the weekly changes in the monkeys’ activity level is the frequency of boat visits per day.…”

“…The pronounced 7‐day periodicity of the average daily activity of the spider monkeys kept on the island (Figure ) seems to be related to the frequency of tourist boats visiting the island. Pérez‐Galicia et al () reported that this kind of human leisure‐time activity is highest during the weekend. Since this is the only—or at least the most obvious—factor with a corresponding 7‐day rhythm in these monkeys’ environment, it seems reasonable to assume that their weekly activity peak was induced by the marked increase (up to 3‐fold) in tourist activity on Saturday and Sunday.…”

“…A recent observational study carried out on free‐ranging spider monkeys kept on a small island (Tanaxpillo) in Lake Catemaco, Veracruz, Mexico, revealed that the frequency with which tourist boats visit this island affects the vocal, self‐directed and agonistic behavior of the monkeys (Pérez‐Galicia, Miranda‐Anaya, Canales‐Espinosa, & Muñoz‐Delgado, ). Given these empirical results, it might be expected that also these monkeys’ naturally entrained circadian activity rhythm may be influenced differently by the varying visitor activities.…”

“…that the varying frequency of tourist boats visiting Tanaxpillo Island over the course of the week would also affect the spider monkeys’ diel activity rhythm. In this case, at least some of its parameters should show differences between the working days (Monday–Friday) and the weekend (Saturday, Sunday), when the number of motor boats taking tourists to the island is highest (8.6 ± 2.5 boats/hour on weekends vs. 2.7 ± 1.2 boats/hr on weekdays; Pérez‐Galicia et al, ). In addition we expected (2.)…”