Danum Valley covers 438 square kilometres of primary dipterocarp forest with an intact canopy exceeding 90 metres. Long before the forest floor receives any direct light, the resident wildlife begins a highly structured acoustic sequence. You will understand the early alarm when you step onto the suspended walkway to hear the birds.
The resident Bornean gibbon dictates the start of the Danum dawn chorus. The male gibbon solo call is a realistic target to open the morning. Research places the median start time for these solos at 5:46am. As the gibbons claim the high frequencies the terrestrial birds dominate the low frequencies.
"A male solo is a long and resonant song that carries for kilometres across the valley."
The eight hornbill species
Borneo hosts 8 species of hornbills and all 8 maintain resident populations at Danum Valley. You hear a hornbill on most stays long before you establish a visual line of sight. Strangling fig trees draw hornbills to feed. A single fruiting fig tree attracts Helmeted, Rhinoceros, Wreathed and Bushy-crested hornbills simultaneously during feeding frenzies.
The Rhinoceros hornbill lacks under-wing coverts. Its wingbeats produce a heavy whooshing sound comparable to a steam engine. The birds fly over the canopy in pairs or small family units. The Wreathed hornbill is highly nomadic and travels in direct high-altitude flight across the valley to locate fruiting events.
Places to listen
Your physical location alters your perception of the dawn chorus. The Borneo Rainforest Lodge canopy walkway is suspended high above the forest floor where you can listen among the canopy birds. Standing here places you directly in the acoustic transmission zone of the gibbons and canopy birds. A construction and expansion project runs at Borneo Rainforest Lodge from 1 January 2025 to 22 January 2027 to add 9 chalets.
At ground level the dynamics change completely. The trail network soundscape is dominated by the low-frequency booming of the argus and the rustling of terrestrial species. The Danum Valley Study Centre offers rigid observation structures and a 6am dawn walk nearby to listen to the morning calls.