National Zoo and Aquarium unveils new animals Cian and Tunku the Siamang gibbons

Although they appeared nervous at first the Siamang's were soon flaunting their swinging skills to the public in their "specially built aerial course".

Senior Wildlife Keeper at the Zoo Renee Osterloh said the gibbons, six-year-old male Cian and 11-year-old female Tunku, would also be part of a breeding program.

"We're part of the Zoo and Aquarium Association, where we work together with our breeding programs. These two have actually been genetically linked to be a part of [one] here."

Ms Osterloh says that the Siamang's were brought to the National Zoo and Aquarium from other zoos and were meeting for the first time.

"Cian was actually born in New Zealand at Orana Park Zoo. He's been living with his father and other brother [as] part of a bachelor group over there [and] Tunku came from Mogo Zoo in the south coast of New South Wales."

The breeding program highlights that Siamang numbers are dropping significantly, says Ms Osterloh.

"They are what we classify as an 'endangered species', which means that their numbers are dropping in the wild [and] we need to look at creating a security population in captivity and increasing our genetic diversity."

The destruction of their natural habitat in Sumatra, Thailand, and the Malay Peninsula is a major concern.

"Their habitat has been affected by deforestation, palm oil plantations as well as, unfortunately for Siamang's, the pet trade [which] is also quite common for them."

For Cian and Tunku though, swinging across the aerial course and gorging on fruit, that now seems a world away.

Billed as a major attraction for the Zoo, the two Siamang's will be a real highlight for a curious public says Ms Osterloh.

"When they start vocalising you'll be able to hear them from up to three kilometres away … and they have quite a large throat pouch that will expand to almost the size of their head when they start to call."

"It acts as like a boombox … and anyone in the park will be able to hear them and almost immediately be attracted to come and see them, to see where that noise is coming from."

For parents and kids currently in the school holidays, the opportunity to see the Siamang's swing across the course is one which Renee and the other zookeepers hope many take up.

"We would really like to encourage visitors to come along, observe them, enjoy watching them … and learn about them."