They spend most of their life in the trees. Siamangs cannot swim and avoid the water. LIFE SPAN Siamangs live about 35-40 years. They do not do very well in captivity. They are fully grown and able to reproduce at 5-7 years old.
Newborn siamangs are hairless except for a small cap of fur on the top of the head.
Babies weigh only about 6 ounces at birth. Female siamangs carefully nurture their young. Babies can grasp their mother's fur to cling to the mother's belly soon after birth. They are weaned at about 1 year old. Young siamangs stay with their mother for about 5-7 years.