Silent Vanishing Crows of Dhaka: A Warning from The Skies

Generations of Dhaka’s residents have awakened to the cacophony of cawing crows — an unofficial alarm clock and a soundscape as intrinsic to the city’s identity as the Buriganga River or its relentless traffic. Once upon a time, Dhaka’s skies and streets were alive with the raucous calls of crows—clever, noisy and ubiquitous. Immortalized in the works of artists like Rafiqun Nabi, through his iconic Tokai cartoons, the crow has long been Dhaka’s unacknowledged and unpaid sanitation worker.

Yet, over the past decade, this once-common resident has been slowly and silently disappearing. Today, that familiar soundscape has grown eerily quiet. Bird enthusiasts, environmentalists and city dwellers alike are noticing the ominous absence, viewing it as a symptom of the capital’s deteriorating ecological health. The decline in crow numbers across Dhaka is no coincidence; it signals deeper environmental distress driven by unplanned urbanization, habitat loss and pollution. Experts suggest the decline is real, rapid, and deeply concerning.

Although official statistics are lacking, ornithologists and nature lovers unanimously observe a marked reduction in crow populations across once-crowded areas such as Ramna Park, Suhrawardy Udyan and the Dhaka University campus. This sudden dip may signal a larger environmental crisis, where the disappearance of one species reflects an impending ecological collapse fueled by unplanned development.

The City’s Unpaid Scavenger
The common crow (House Crow, Corvus splendens) is more than a bird; it is a crucial component of Dhaka’s urban ecosystem. Often called the “Health Inspector” or “Scavenger,” it performs a vital service by foraging on food scraps, waste and carrion—naturally disposing of refuse that might otherwise spread disease. Crows act as nature's clean-up crew, maintaining hygiene and controlling disease vectors.
Professor Dr. Anwarul Islam, former Chairman of the Zoology Department at Dhaka University, emphasises the crow’s “incalculable” value. As renowned ornithologist Salim Ali once argued, every species—from insect to mammal—is an indispensable bead in nature’s garland. When one bead falls, the entire system weakens. Similarly, the crow’s disappearance shifts an immense burden back onto a city already struggling with waste management.

“Crows are an integral part of the ecosystem,” explains Dr. Aminul Islam Bhuiyan. “They play a vital role in maintaining nature’s cycle. When this chain is broken, the effects are often invisible at first—but over time, they lead to environmental breakdown, especially in densely populated cities like Dhaka.”

The Assault of Unplanned Urbanization
The forces driving the crow toward local extinction can be collectively described as the Urbanization Onslaught. Experts have noted that crows, once considered one of the most adaptable urban birds, are rapidly disappearing from cityscapes. Professor Dr. Aminul Islam Bhuiyan of the Department of Zoology at the University of Dhaka highlights that three major factors lie behind the decline: habitat and food shortages, unplanned development and the proliferation of mobile towers.

Habitat loss is the foremost cause. Unplanned urban expansion and rampant deforestation have destroyed the large, mature trees that crows rely on for nesting, roosting and shelter. Unplanned urban expansion has stripped the city of its large trees—once home to countless crow nests. The city’s “vertical expansion”—high-rise apartments replacing leafy homes with gardens—has simply erased their breeding grounds. The loss of green cover has deprived the birds of both shelter and food.

Adding to this is technological overload. The proliferation of mobile towers across Dhaka is widely believed to be a major threat. The radiation emitted by these towers disrupts birds’ biological systems, affecting their navigation, breeding cycles and survival rates. Moreover, modern development projects are dismantling the very infrastructure crows use. The effort to move electrical wires underground removes the sprawling network of overhead cables that crows once used for perching, resting and socializing. Finally, rising temperatures due to climate change add another layer of risk, affecting reproduction and reducing survival rates. Collectively, these stressors form a perfect storm that is pushing crows—and many other species such as sparrows, butterflies and bats—toward disappearance from urban environments.

Toxic Diet and Environmental Poisoning
While crows have long thrived on urban waste, that very source of sustenance has turned toxic. The shift in urban pollution has transformed their diet into a deadly cocktail.

The most alarming threats include poisonous waste and contamination. Toxic waste, formalin-treated food (commonly used to preserve fish and fruit) and widespread pesticide and insecticide use on dumped refuse directly poison the birds and have further endangered their health and disrupted breeding cycles. Modern waste also contains higher concentrations of plastic and metal particles, which, when ingested, cause chronic illness and organ failure.

Researchers have also linked the decline to avian diseases. Crows feeding on improperly disposed poultry carcasses infected with Avian Influenza (H5N1) risk contracting the virus, further accelerating the population collapse.

A Vicious Cycle and a Call to Conscience
Environmentalists warn that this decline is more than just an ecological curiosity; it’s an early symptom of urban ecological collapse. The disappearance of crows is not just an ecological loss—it’s a public health warning. When the city’s natural sanitation service breaks down, waste accumulates, attracting rats and insects and fuelling disease outbreaks. Their absence could have cascading effects on human health and the urban environment.

The decreasing presence of crows is a mirror reflecting our unsustainable relationship with nature. The decline of the crow population mirrors a development model that prizes concrete over canopy and profit over preservation. As Professor Anwarul Islam warns, the first loss will be emotional—a city stripped of one of its most familiar sounds. The second will be practical—the soaring challenge of managing waste and pollution that the crow once handled free of charge.

To prevent Dhaka from sliding into an ecological vacuum, urban planners, policymakers and citizens must act—by preserving trees, managing waste responsibly and ensuring that technological expansion respects the natural balance. The survival of Dhaka’s crows is not merely about birds; it’s about the soul of the city itself.

 
Raghu Nath Raha is a 
development professional 
and a social welfare consultant.