Siamangs
Learning Goal
Learn what makes siamangs unique and compare yourself to a siamang!
Introduction to Siamangs
Siamangs live in tropical mountain rainforests in family groups just like you and I. Their range is in Asia: south of Thailand in the Malay Peninsula and Sumatra where it is warm and rainy. They have shaggy black fur covering their whole body. Their arms and legs are similar to those of a human. They also have a unique pink bubble on their necks called a throat sac. Although siamangs are similar to humans in many ways, their bones are much lighter and their arms much longer, making them perfectly adapted for life in the trees.
Close relationships are important for siamangs, as they protect and learn from each other and work together when foraging for food or protecting their home territory. Their groupings are flexible and can change over time as individuals grow older. However, a mated pair of siamangs will stay together for life. Most groupings consist of two adult parents and their children.
For siamangs, life has a daily rhythm as they follow the same routines each day: waking and “singing,” grooming and resting, then going out in search of food. At the end of the day siamangs settle down for the night, cozying up in the crooks of trees—unlike gorillas they do not build nests; they just sleep in branches. Siamangs are diurnal, meaning they’re active during the day. They are omnivores: they forage for fruits, vegetables and nuts, and supplement their diet with insects, bird eggs, and occasional small animals.
Siamangs perform a daily concert or duet along with an acrobatic show each morning high up in the tree tops. Their deep calls echo into the jungle and tell other siamangs and animals that this area is their territory. Unlike some animals who may want to hide and not be seen, siamangs make sure that everyone knows they are there and will fiercely protect their home. They bellow out their calls for all to hear while jumping and swinging through the trees in amazing feats of gymnastic skill: they somersault and catapult themselves through the air with incredible balance and precision.
Siamangs create different sounds by inflating their throat sac like a balloon and breathing into it. Their grayish-pink throat sacs are important because they enable them to communicate. Siamangs can sing with their mouth open or closed—when their mouth is closed, the air goes into the throat sac making a deep booming sound. If the siamangs have their mouth open and sing into the throat sac, it creates a loud “wow” sound. Each song is different, as each siamang is different. Siamang pairs sing to each other, creating their unique harmony.
Although they sing every day to broadcast their presence, actual fights between siamang groups are very rare. The loud howling each day allows siamangs groups to be very aware of each other and keep their space. This is important so that the family group can get the resources and food they need. If there ever is a challenge over group boundaries, siamangs will bite and slap their rivals in a high-speed chase through the trees. This happens rarely; the vast majority of the time siamangs play a peaceful role in the rainforest, eating fruits and spreading seeds.
Siamangs at the ABQ BioPark
You can hear the siamangs “singing” at the BioPark nearly every morning and sometimes throughout the day depending on if the group feels the need to emphasize that the BioPark is their territory to perceived rival siamangs. This is the same natural behavior you would see in the wild, as most siamangs call out around dawn when the sun rises. The best time to hear the BioPark’s siamangs “sing” is around 9-10 a.m.
The BioPark’s two adult siamangs are named Brian and Johore. Siamangs usually grow their family every two to three years and Brian and Johore are no different. They have had three babies. In 2010 they had baby Noah, in 2014 they had baby Tika, and in 2016 baby Eerie.
When Noah was born, first-time mother Johore still needed practice at being a mother, so Noah ended up being hand-raised by humans before finding a surrogate siamang mom at the Tulsa Zoo. Different facilities within the Association of Zoos and Aquariums (AZA) are able to work together in order to make sure all animals have what they need. It was great that although things did not work out with Noah’s actual parents that we were able to find him a place and surrogate mother who was right for him at that time.
Once Tika was born, Johore and Brian were up for the job and have been successful parents ever since. For the first three to four months of life baby Tika, and later Eerie, clung to their mother Johore as they would in the wild. After about 6 months, the fathers step in and take a more active role. Both Johore and Brian have turned out to be great parents to Tika and Eerie. Eerie is now 3 years old, so she still has some growing and learning to do. By age 6 or 7, siamangs are fully grown adults and may start a family of their own. Tika, who is three years older than Eerie, has proved to be a great big sister.
It is important for siamangs to learn from each other and especially from their adult parents. Tika has been able to learn a lot from her parents about infant care by watching her parents care for baby Eerie. Both babies learn how to vocalize and “sing” from their parents. Both Tika and Eerie started joining in with the morning chorus when they were about 2 years old.
Females are in charge in the siamang world, so Johore is leader of the group. If she wants something like food or treats she can simply take it from Brian and he doesn’t put up any fuss. The communication between Johore and Brian can be subtle to us, but to them meaning is very clear. You might hear the siamangs communicating in a variety of ways: in addition to the singing/howling they do each morning, they also chirp and bark, and occasionally Johore might flash her teeth at Brian to say, “Stay away from me. I want space.”
To keep life exciting, caretakers constantly provide the siamangs with new enrichment items and habitat set-ups, and a varied diet. The BioPark’s siamangs a plethora of fruits and vegetables, mimicking their natural diet. They need lots of greens, more so than other types of gibbons, so the siamangs get lots of kale, cabbage and lettuce. They also enjoy eggs on occasion, green beans, carrots, apples, bananas, oranges, sweet potatoes and more. By mixing up how the ropes and “vines” are set-up in their habitat, the siamangs can find new ways to creatively navigate their surroundings as they would in the wild. Toys like balls, a play-house, and paper treat bags are just a few of the ways the BioPark’s siamangs stay active, healthy and stimulated.
Siamang Conservation
Siamangs do not have many predators. They are quick and agile enough to avoid most dangerous situations although, on occasion, some will get snatched by large birds of prey. Their biggest threat, like most animals, is habitat loss. The other biggest threat to siamangs living in the wild is the pet trade. Wild siamang populations are decreasing, making education and awareness about the species more important than ever.
Siamangs are considered endangered by the International Union for the Conservation of Nature (IUCN). This is a problem not only for their species, but also for the rainforests as a whole because siamangs play an important role in seed dispersal (the spread of fruit seeds). The fruit they eat and defecate has lots of seeds in it, and when they move from one place to another, the siamangs bring the seeds and new opportunities for growth. The variety of fruits they eat also makes them of crucial importance within the ecosystem. They have been documented eating more than 160 different types of plants, which means that if siamangs suddenly disappeared, more than 160 plants would be impacted and may not spread or grow as much. Other plants and animals would also be affected by this chain of events and would also lose food and shelter resources. Without siamangs traveling and foraging into new spaces, the seeds that they eat would never find their way to new spaces to grow, and the biodiversity of the whole ecosystem would suffer. Even slight changes in wild siamang populations can have a big impact years into the future. To keep the forest healthy and diverse, siamangs need to be protected so they can do their “job” within the rainforest.
You can help siamangs by making thoughtful purchase decisions when it comes to palm oil. Palm oil is found in roughly half of all packaged food and cosmetics making the demand so high that habitat of siamangs and other species must be destroyed to create palm oil plantations. The ABQ BioPark supports the purchase of certified sustainable palm oil. You can find an updated list of companies that use sustainable palm oil here: https://www.cmzoo.org/conservation/orangutans-palm-oil/palm-oil-tool-kit/
You should never have a wild animal like a siamang as a pet. You can also spread the word to educate others to do the same to help diminish the illegal trade of not only siamangs but many other species. By educating others, supporting the ABQ BioPark and the siamang breeding programs there, and getting informed about the palm oil industry and illegal pet trade you are supporting siamang populations and making a difference.
Activities
Make Your Own Throat Sac!
Use a balloon to experiment with what it would be like to have a throat sac!
Materials:
- One balloon
Directions:
- Blow up a balloon as much as you possibly can.
- Let out air and experiment with the different noises a balloon can make depending on how fast you release the air.
- Experiment with filling the balloon partially up and seeing if there are different sounds that way.
A siamang basically has a balloon on their neck! They have incredible control over the amount of air they can place inside or release from the balloon.
- Draw a picture or write a short paragraph showing what you learned from this experiment. You may want to use the following questions:
- What do you think it would be like to have a “balloon” on your neck?
- What could you use the balloon for?
- What allowed you to make the most noise with your balloon? The least?
- Were you able to make different noises or did they all sound basically the same?
How Long are Your Limbs?
Materials:
- One tape measure
- Graph paper
- Pens/pencils/drawing utensils
Directions:
- Measure how tall your total body is from head to toe and write this number down.
- Measure how long your arms are from the tips of your fingers all the way across your chest.
- Use graph paper to diagram your own body and the body of a siamang, comparing your total height and the length of your arms.
- A siamang typically is about 3 feet tall or less and has an arm span of about 5 feet!
- Who is taller, you or the siamang? Who has longer arms?
- Answer the following question through writing, drawing or verbally:
- Why would siamangs need such long arms? How have they adapted for life in the trees?
- How is your body suited for what you as a human do? Do humans mostly swim, fly, climb, walk or run?
Sing a Siamang Song
Here is your chance to get really creative! Make your own unique sound or song and perform it the same way a siamang would! You may express yourself musically in a variety of ways.
Materials:
- Paper
- Writing utensil
Optional:
- A friend to duet with
- A musical instrument (drum, recorder, etc.)
Directions:
- Pick a few key sounds/notes that are important for your song. Write these down possibly by using musical notes, writing “high note/low note” or even drawing what it might look like when you make that noise. These are your directions on how to make your song, so you should choose whatever method will help you remember best.
- Decide what your song is hoping to convey. A siamang’s song helps mark their territory but also strengthens the bonds and relationships with a group. You may want to have especially loud noises if you have a larger territory. If working with a friend, you may want to have your songs work together to sound even better.
- After rehearsing, perform your song for an audience or for yourself. Ask yourself the following questions (you may discuss these with friends as a group or write down your ideas):
- What would it be like to perform your song every day?
- How might a siamang’s song be similar to or different from human music?
- What makes for a successful song (either for yourself or as a siamang)?
Remember there are no wrong answers here with any of these experiments as long as you can be creative and experiment with what it might be like to be a siamang for the day!
Additional Resources
Listen to the sounds of a siamang here: Wild Ambience - Siamang
Watch siamangs at the El Paso Zoo here: Siamang Playground
Sources
https://nationalzoo.si.edu/animals/siamang
https://animals.sandiegozoo.org/animals/siamang
https://www.rainforestanimals.net/mammals/siamang/