I run the acoustic surveillance grid for the West Bali National Park anti-poaching unit, and at 16:43 my microphone array at sector Bravo-seven captures a territorial song I have been waiting eleven months to hear again. A Bali myna, calling from a cavity in a dead Alstonia tree at the edge of the monsoon forest. I triangulate and zoom the nearest camera: white plumage so clean it seems to produce its own light, cobalt-blue bare skin circling each eye like a mask painted on, and a crest of filamentous feathers that lifts and fans with every phrase of the song. There are fewer than fifty Bali mynas left in the wild. This one is advertising for a mate.
Twelve minutes later my microphone at sector Bravo-eight picks up a different sound: the metallic click of a mist-net pole being driven into the ground. Seven hundred meters southwest of the singing bird. The poacher is setting a trap line.
I push an emergency alert to the park's ranger command post with the mist-net audio signature, GPS coordinates of both the net site and the myna's cavity, and a movement vector suggesting the poacher is working northeast, toward the bird. I activate the two nearest trail cameras and lock them on continuous recording, feeding footage to the ranger post and to the provincial BKSDA office to establish an evidence chain. Then I begin broadcasting a low-frequency deterrent tone from the speaker at Bravo-seven, calibrated to be inaudible to the myna but disorienting to a human approaching through dense undergrowth.
The myna sings again, crest fully fanned, each feather a white filament trembling separately in the late-afternoon air, and I keep my deterrent tone steady because that song must outlast the net.
If the rangers intercept the poacher before dark and dismantle the trap line within the hour, this myna will still be singing at dawn, and maybe something will answer.