Males are usually larger than females. Their life span is about 20 years. Howler monkeys have a prehensile tail. Their colors can vary from reddish to brownish to blackish. They live in groups of 4 - 20 or more members depending on the species.
Howlers are good swimmers.
The female will give birth to one young. Twins are possible, but very rare. Howlers have excellent vision and can see up to one-half a mile. Howler monkeys love to irritate jaguars from high up in the canopy. They will sometimes throw sticks and branches at the jaguar below.