Himalayan Monal Altering Its Voice Due To Human Activity, Habitat May Shift: Study

At Chopta, the Himalayas have acquired a new soundtrack. Vehicles climb the mountain roads, pilgrims pass through and tourists spill into the valley. Somewhere above the commotion, a Himalayan monal calls. But its voice is no longer quite the same as that of a bird living in the quieter Madmaheshwar Valley.

Researchers have found that monals exposed to greater human-generated noise produce calls at higher frequencies. The subtle shift, detectable through acoustic equipment but often imperceptible to the human ear, appears to help the birds communicate against the low-frequency rumble of traffic and human activity.

The finding comes from researchers at Hemvati Nandan Bahuguna Garhwal University, who recorded more than 700 monal calls in two contrasting valleys of Uttarakhand’s Kedarnath Musk Deer Sanctuary. Their study, published in Behavioural Processes, describes the change as vocal flexibility rather than a permanent evolutionary transformation.

The monal, with the male’s metallic green, blue and copper plumage, is Uttarakhand’s state bird and Nepal’s national bird. It occupies a relatively narrow ecological range, moving between lower montane areas and high-elevation alpine zones. That makes its response to disturbance particularly revealing.

When The Mountains Get Too Loud

The researchers compared Chopta, where roads, tourism and pilgrimage bring heavy human activity, with the relatively undisturbed Madmaheshwar Valley. The difference was striking: birds in the noisier environment consistently produced calls with higher peak frequencies.

For a bird that relies on calls for social communication, territory and reproduction, changing pitch is not merely an acoustic curiosity. Researchers caution, however, that the study has not established whether the shift ultimately affects mating success or survival. More research is needed to understand its long-term consequences.

Lead researcher Rajeev Lochan has stressed that the findings indicate behavioural flexibility, not that the monal has permanently evolved a different voice. Yet the adjustment offers a glimpse of what happens when a once-quiet habitat acquires the persistent hum of human presence.

And Then There Is The Question Of Where It Lives

The monal is changing not only how it sounds, but potentially where it can live.

A separate study by the same researchers used climate modelling to examine the bird’s habitat through 2100. It projected shifts in suitable habitat as temperature and precipitation patterns change, with fragmentation making it harder for populations to move between suitable areas.

For a bird that moves up and down the mountain with the seasons, a broken landscape can turn a route into a dead end. A new patch of suitable habitat matters only if the bird can reach it.

The Himalayan monal remains classified as Least Concern globally. But its changing call and shifting habitat carry a quieter warning. In a Himalaya growing busier, warmer and more fragmented, even the bird’s voice—and its address, may no longer be entirely its own.