Sydney Cahoon, University of Utah
Pre existing research has been conducted to observe during which seasons howler monkeys eat and sleep the most. While it was found that they eat and nap intermittently throughout the day, there has been no prior research done to record the times during the day that mantled howler monkeys (Alouatta palliata) consume the majority of their food. Due to social foraging with addition to the benefits of consuming the food earlier during the day to better assist in filling daily activity budgets, it was hypothesized that a greater part of consumption will take place during the mornings (08:00-12:00), and less in the evening (14:00-18:00) before they sleep. Data were collected in May 2017 at La Selva Biological Research Center in Sarapiquí, Costa Rica over the span of 40 hours where majority of data were collected between 08:00-19:00. Observations were made using five-minute interval scan samples. The majority of the data were collected at the station’s arboretum trail (SURA) and along the Rio Puerto Viejo River. Data were collected in these areas multiple times, in order to survey the same group of howlers in those locations over the span of several days before the group moved to a different section of the forest. The results showed that 9.3% of feeding occurred in the morning (08:00-12:00), 23.3% in the afternoon (12:00-14:00), and 67.4% in the evening (14:00-19:00). Based off of a study, it was shown that howler monkeys typically took 16-22 to digest their food. Since howler monkeys are diurnal and therefore spend the majority of their energy during the day, it would be understandable if sustenance consumption took place the evening prior. Ultimately, understanding what specific foods are eaten during specific times of the day can help us learn where they will be located geographically. This can further assist nature conservationists in recognizing what plants and trees would need to be introduced or reintroduced back into the environment should howler monkeys ever be in an endangered situation.