Encounters with the vocalization of Howler monkeys are a common occurrence when visiting in Costa Rica. Their distinctive deep guttural vocalization is unmistakable and surely makes the visitor nervous when hearing it for the first time. I tend to hear the vocalization of the Howler mostly in the early morning hours which is a rather eerie way to wake up.
Not to fear, although their vocalization is fearsome, they are a docile bunch of monkeys with a purely vegatarian diet and the most aggressive behavior toward people is peeing on them as a means to keep them from getting to close to their perch in the tree. You use whatever resource at your disposal right..?.. And I will admit this is much more preferred treatment from monkeys than them throwing poop at you as a means of exercising their territoriality.
chilling
Because their diet is exclusively vegetarian, they do not have a lot of energy to expend and are thus much less active than other monkeys. In fact, they spend most of their time just laying around chilling. I would say that they fit right in with the vibes here in Santa Teresa where the afternoon siesta is a sacred daily ritual for most.
Their diet consists of the young foliage of trees and they very seldom come to the ground. They are known to have an adaptive three color vision in order to discern the younger leaves from the sometimes more heavily laden with toxins - older leaves. Most monkeys have a two color vision and have a more omnivorous diet. The diet includes mostly leaves, but also flowers and fruits depending on the season. The types of leaves, fruits, and flowers in the Howler monkey's diet vary widely and thus this species of monkey has a very wide range and is able to survive in many different types of habitats.
Howlers are famous for the incredible vocalizations made by adult males. Their howls have a long distance range and it is said that they can be heard for more than 1 km away through the forest. It is believe that the range and ability to howl are an adaptive feature allowing the monkey's to communicate within their social groups with out having to expend energy and move.
Interestingly howlers are such a successful monkey in Costa Rican forests, that it is believed that they constitute upward of 60% of primate biomass within the country. Meaning that of all the different species of monkeys in CR, they measure over 60% of the weight!
While they do eat a wide range of different types of plant parts found in different bio-regions, they are very choosy eaters, and often only eat certain parts of an individual tree and other parts of a different tree. They are the primate equivalent of a "foodie". From one tree they may choose mature leaves, young leaves, flowers, the petioles or the pulvinus of leaves. They also seem to base their food choices on how much the plant contains protein, fiber, and levels of alkaloids and tannins. How is that for a particularly choosy eater?... I can think of a number of my well-meaning (hipster) friends that survey the menu based on nutritional content or celestial alignment,.. meanwhile I'm like "I'll have a burger, thanks!".
Hipsters in their natural habitat
howler in it's natural habitat
Two fun Howler monkey FACTS!!
- The mantled howler is important to the rainforest ecology as a seed disperser and germinator.
- When the males reach maturity, the scrotum turns white.
sexually mature and proud of it