These photos above of a male Howler Monkey were taken by my sister, Barbara, who with her husband Greg were staying at our Costa Rica treehouse in the Pura Jungla eco-reserve – they have been there twice and Barb has just recently booked for early 2017.
This fellow was enjoying eating some white flowers on the tree just outside the treehouse second guest bedroom window, so Barb stepped out onto the closest viewing platform and from a distance of about five feet took these great photos. There was no need to zoom in ! He was letting her know vociferously, under no uncertain terms, that this was his tree.
Most of our guests over a one or two week stay will delight in seeing these magnificent animals coming by to visit, but never coming into, the treehouse. It is an absolutely unforgettable experience.
Howler monkeys have a short snout, and wide-set, round nostrils. They range in size from 56 to 92 cm, excluding their tail which can be equally as long. They have a lifespan of 15 to 20 years. On average males are 1.5 to 2 kg heavier than females.
Howler monkeys generally move quadrupedally on the tops of branches, usually grasping a branch with a t least two hands or one hand and the tail at all times.
Most Howler monkey species live in groups of 10 to 15 animals, with one to three adult males and multiple females. Physical fighting amongst group members is infrequent and generally of short duration. However, serious injuries can result. Both males and females may fight with each other but physical aggression is even more rare between sexes.
As their name suggests, vocal communication forms an important part of their social behavior.They have an enlarged basihyal or hyoid bone which helps make their loud vocalizations. Group males generally call at dawn and dusk as well as interspersed times throughout the day. The main vocals consist of loud, deep guttural or “howls”. Howler monkeys are widely considered to be the loudest land animal, According to the Guinness Book of Records, their vocalizations can be heard clearly for 20 miles (32 kilometers). It is hypothesized that the function of howling relates to intergroup spacing and territory protection, as well as possibly mate-guarding.
Howlers eat mainly top canopy leaves, together with fruit, buds, flowers, and nuts.