Located in the heart of Riau, Sumatera, Tesso Nilo National Park is home to around 60-80 wild Sumatran elephants. But that's not all, this tropical rainforest also shelters a stunning diversity of life. From rare wild animals to unique plants found only in Indonesia, the park is a true biodiversity hotspot.
First established as a protected forest area by the Indonesian government in 1986, Tesso Nilo originally spanned 38,576 hectares. Later in 2009, its size was expanded to 83,068 hectares to strengthen conservation efforts.
Within this vast area, a wide variety of ecosystems thrive, hosting countless species such as elephants, deer, slow loris, and more.
Tesso Nilo, The Home of Sumatran Elephants
Tesso Nilo National Park is one of the last remaining lowland tropical rainforests in Sumatra. It was specifically designated as a conservation area for the elephant Tesso Nilo, as its habitat provides a relatively safe and sustainable environment compared to other regions.
To protect these elephants living in the wild, Tesso Nilo National Park Authority partnered with WWF Indonesia to create the Elephant Flying Squad in 2004.
This squad consists of four trained elephants and eight caretakers, known as mahouts. Their main task is to guide wild elephants back to their natural habitat whenever they wander into nearby villages. The team also monitors illegal logging, hotspot of forest fires, and poaching activities.
While elephants are the park's most famous residents, Tesso Nilo is also home to other rare wild animals in Indonesia that deserve attention. Here are two species you should know about.
Slow Loris, The Adorable Nocturnal Primate
True to its name, the slow loris is a small primate known for its large round eyes and slow deliberate movements. This slowness is actually a survival adaptation, helping it remain undetected in a world full of predators.
With strong grips on both its hands and feet, slow loris can hang onto branches with remarkable strength and stability. These primates typically live in dense tropical and subtropical forests, including those in Sumatra.
Measuring only about 20-40 cm long and weighing 0.3-2 kg, slow lorises are solitary and nocturnal creatures. Their big eyes allow them to search for food in the dark. While their unique defense mechanism lies in venom glands located near their elbows, used when they feel threatened.
Deer, The Shy Animals of Tesso Nilo
At first glance, the deer found in Tesso Nilo resemble other deer species. They have slender bodies, quick movements, and watchful eyes. These graceful herbivores roam freely across tropical rainforests in Southeast Asia, from southern China to Myanmar, the Malay Peninsula, and Indonesia's Sumatra.
In Tesso Nilo, they can be spotted in various habitats such as secondary forests, open woodlands, and thickets across areas like Air Hitam, Bagan Limau, Onangan Nilo, and Lancang Kuning Air Sawan.
Known as introvert of the forest, deer usually live solitary. They are both diurnal dan nocturnal, meaning they can be active during the day as well as at night.
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On September 8, 2025, Tesso Nilo's official Instagram account @btn_tessonilo shared footage of a muntjac deer (Muntiacus muntjak) freely roaming around the park. These deer looks healthy and unbothered, an encouraging sign of a thriving habitat.
Why Protecting Tesso Nilo Matters
The presence of Tesso Nilo National Park as a conservation area is crucial. It provides a safe haven not only for elephants, but also for countless other species that form part of Indonesia's natural heritage.
Protecting the Sumatran elephant, slow loris, and deer means preserving the integrity of the entire ecosystem. Conservation is not just the responsibility of the government, but also of local communities and even visitors who come to witness its natural beauty.
Tesso Nilo National Park is a reminder that nature's true beauty lies in its diversity. While elephants are iconic, the park's slow loris and deer are equally vital for the survival of the forest.
Protecting these wild animals in Indonesia means safeguarding the future of our environment. By valuing and preserving biodiversity, we ensure that Tesso Nilo remains a living treasure for generations to come.
