‘What we are doing to the forests of the world is but a mirror reflection of what we are doing to ourselves and to one another’ – Mahatma Gandhi

The haunting early morning call of the white-handed gibbon serves as our morning alarm alongside the occasional cry of the Great Argus pheasant in the distance. Hornbills glide between the canopy above and pig-tailed macaques leap across the river, the branches serving as their tightrope. The Leuser Ecosystem, situated in the provinces of North Sumatra and Aceh, is one of the most biodiverse regions in the world. A UNESCO World Heritage Site, the rainforest currently spans over 2.6million hectares, making it the third largest rainforest ecosystem behind only the Amazon and the Congo. It is the only place in the world where critically endangered tigers, elephants, orangutans and rhinos co-exist.

The morning breeze lightly drifted through the tarpaulin, carrying with it the damp scent from the previous night’s storm. I pulled back my mosquito net, and clambered out from our simple, but effective housing. The river that ran alongside our camp crashed and carved its way through the rainforest, the trees running parallel carried a million hues of green under the dappled light, saturated by the water.

We pack our bags, filling our bottles with smokey, boiled river water and set off, searching for our target species. As we walk, evidence of sun bears appears on the bark of the trees; marks that –  for a small bear – sit at the same height as my shoulder.

Sun bear claw marks in the tree

Further down the track, the leaf litter is disturbed, small trees uprooted, and a burrow is visible. A Sunda pangolin. Sadly, the culprit isn’t home, but just knowing that such incredibly elusive and endangered creatures are tucked away in this jade haven, possibly around the corner, is exhilarating.

We meander upstream, passing iridescent blue stick insects and large millipedes; scrambling up rock faces to get a high vantage point over the rainforest. I had expected it to be relatively easy to spot a glimpse of our bright orange subject amongst the verdant leaves. As it turns out, it proved pretty difficult.

We took a rest stop to tuck into a myriad of fresh fruit; watermelons, pineapples and bananas. As I bit into the juicy, yellow fruit, an explosion of flavour filled my mouth. This was unlike any pineapple I had ever eaten back home. It was so full of flavour; juices spilling down my chin as I struggled contain them. Thomas leaf monkeys look on, envious of my meal.

Thomas leaf monkey watching us eat

I stand up, stretching my tired legs from the climb up to our snack spot. I twist myself around, eager to taste another banana from the supply at my feet; but before they reach the ground, my gaze meets a set of mahogany human-esque eyes, not even 10 metres from where I stood.

I cry out ‘orangutan’ and everyone springs into gear, our guides crossing the clearing and grabbing the food at mach speed while we reach for our bags. He is determined, he knows we have fruit. Had I not turned around, he would have been upon us without us even realising; for such a powerful creature, he moved silently.

Face-to-face with a male orangutan

As an almost exclusively arboreal species, this encounter was even more extraordinary. Unlike their Bornean counterparts, Sumatran orangutan males rarely travel on the ground, but here he was. His impressive cheek-pads frame his face, signifying his dominance, for he is the ruler of this rainforest and we humans do not belong here. He could easily pull our arms from their sockets if we blocked his way. He moved into the clearing where we had just been sitting and searched for any remnants of our meal. My heart was pounding, desperate to escape from its bony cage, as I shared the same space as this impressive creature.

Currently listed as Critically Endangered on the IUCN Red List, around 80% of Sumatran orangutans call the Leuser Ecosystem home. The survival of this charismatic species is threatened immensely by large and medium-scale clearing of forests for palm oil, with plantations currently standing in the place of 80-90% of Sumatra’s pre-human rainforest.

I think how my body aches to be back there, surrounded by the giant, silent sentinels of the forest, guided by the songs of its inhabitants. However, this magnificent ecosystem is currently under grave threat, suffering from one of the highest rates of deforestation worldwide. In just the last 20 years, over 110,000 hectares have been destroyed. The protection of this priceless ecosystem must be preserved; if it is to be saved, companies must stop clearing rainforest for palm oil. The survival of the orangutan – and the hope for future generations to witness these wonderful ecological havens – depends on it.