- Padfoot the Painting Ocelot
- Unique jaguar makes public debut
- Jaguar gets new smile thanks to Valley team
- Rhinoceros Hornbill Chick
- New Jaguar on Exhibit!
- Zoo Babies! Black Footed Ferrets
- Positive Effects for Andean Bears
- Learn More About Phoenix Zoo Animals
- Budgett's Frog
- Poison Dart Frogs
- Patagonian Cavy
- All About the Desert Tortoise
- The Turkey Vulture
- Meet the Phoenix Zoo Meerkat Family
- The American Bald Eagle, Our Nation's Symbol
- Ruppell's Griffon Vulture Facts
- Facts About the Common Raven
- Undulated and Laced Moray Eels and the Coral Reef
- Giant Vietnamese Centipede
- The Phoenix Zoo's Asian Elephants
- When It Comes to Bird Beaks, Size Does Matter
- Petting Zoo at Harmony Farm
- Wild Dogs
- My Arts Community
Each morning at the Phoenix Zoo, you can hear the call of the siamang, a primate in the same family as gibbons. Siamang calls are legendary. All gibbons can make amazingly loud sounds, and the siamang's "song" includes booms and barks, made louder by the inflatable throat sac. When enlarged, the throat sac can be as big as a human head! These throat sacs are used as a sound box to amplify their loud vocalizations. The booming calls of the siamang can be heard up to two miles away through the forest. The calls are used primarily for claiming territory, which can be as large as 50 acres. First thing in the morning, a family's adult female will usually start a territorial hooting that the others join, and the noisy warning to other siamang families can last 30 minutes. Paired males and females also sing duets to one another, and each pair creates a unique song all their own!
Siamangs (a lesser ape) are arboreal, black furred gibbons and the largest of the of the 14 species of gibbons. In fact, they can be twice the size of other gibbons weighing between 22 to 26.4 lbs and a head-body length from 27.95 to 35.43 in. They are native to the forests of Malaysia, Thailand, and Sumatra and are well-suited for life in a forest's treetops. Their main mode of transportation through the rain forest is by brachiation. The motion of their arms looks like the left-right motion of striding legs. During brachiation, the siamang hangs from a branch by one hand while swinging its body around to allow the other hand to grasp the next handhold. When moving slowly, they swing much like a pendulum as they grab one branch and let go of the previous one. When moving quickly, they often release the previous branch before grabbing the next, so that the body is freely projected through the air. They are very acrobatic and agile. Their extra-long arms help them cover up to 10 feet in a single swing. If they're not swinging through the trees, they're very likely walking along branches with their arms outstretched to help them keep their balance.
Siamangs' arm length may be over 2 times the length of their body (and longer than their legs) which allows for their success in swinging through the trees. In fact, their arm span may be as wide as 4.9 feet. They have a short-muzzled face that is nearly hairless, accompanied by a large brain case and have hands are a lot like ours - there are four long fingers and a smaller opposable thumb. Their feet have five toes like we have, but their big toe is opposable too. One other thing that sets the siamang apart physically from the other species of gibbons is webbing between their second and third toes. Both sexes are black and have long canine teeth.
Siamangs set out in the morning (after their 'concert') in search of food. They survive mainly on leaves and fruit, but also eats insects, bird eggs, and small vertebrates. In the dry season the length of the Siamang's daily range is longer than in the rainy season. The Siamang in southern Sumatra undertakes less foraging than the Siamang in other places because it eats more fruit and therefore consumes more nutrition, which results in less time needed for looking for food. It usually takes a siamang about five hours to eat its fill and, after about 8 to 10 hours of activity, it returns to its sleeping place.
Siamang pairs usually stay together for life and do not usually take another mate if the first one dies. The family group consists of one adult male and one adult female, along with two or three immature offspring . The gestation period is 230 to 235 days (7 months) and females typically give birth every 2 to 3 years to one young, but twins sometimes occur. The infant is weaned at 18 to 24 months and reaches maturity at about 6 to 7 years. Baby siamangs are born hairless except for a small tuft on top of the head. Infants can hold onto their mothers' fur and cling to her belly soon after they're born. The youngster is weaned early in its second year. The father does his share of raising the baby and takes over the daily care of the youngster when it is about one year old. This is unusual for most other primates. Young siamangs stay with their families for approximately five to seven years. Then they venture out on their own to start their own family group.