Where have Dhaka's crows gone?

A house crow—once the defining sound of Dhaka’s mornings, now a rarity. Photos: Muntasir Akash

Crows are now a rarity in Dhaka. For years, my birdwatcher friends raised alarms about the slow disappearance of this familiar urban bird. At first, I dismissed their warnings. But since returning from Scotland in 2024, I too have noticed a fundamental shift — the morning soundscape around my residence has grown oddly muted. Across neighbourhoods, people pause and ask the same question — where did the crows go?

There was a time when dawn in Dhaka broke with a trademark cacophony — not traffic horns or construction drills, but crows. Dozens of them called from rooftops, electric wires, and whatever greenery remained within the maze of concrete. In the mornings, they circled over kitchen markets and dumpsters, arguing over scraps and satisfying their curiosity with anything that seemed unusual. As evening fell, they gathered in noisy roosts. For Dhaka's residents, crows were a constant background presence — irritating, familiar, and impossible to miss.

However, the disappearance has been a quiet one. It has unfolded silently, the way many urban ecological crises do — one fewer bird on a rooftop, a roost that no longer forms at dusk. People notice the absence instinctively, long before science catches up. As I write this, the morning outside feels eerily devoid of crows.

A bird born for cities

There are around 40 to 47 different crow species, found on every continent except Antarctica and most of South America. They inhabit the high Himalayas and the freezing shores of the North Sea. Crows can be seen on remote Pacific islands and in the dense jungles of Central America.

All crows are known for their highly advanced cognitive abilities and complex social behaviours, which have sparked human interest for millennia. I remember when my mother first showed me the depth of their intelligence. On a rooftop in the '90s, moments after she waved a black cloth tied to a pole, nearly a hundred house crows gathered, visibly agitated, as if they believed one of their own was in distress. 

Crows' intelligence has shaped human culture. The raven is the national bird of Bhutan, symbolising wisdom, authority, and protection. So much so that the Raven Crown — surmounted by a raven's head — is worn by the Dragon Kings of Bhutan.

Their Latin name Corvus also names one of the 88 constellations. Many crow species are adapted to thrive alongside humans. Across South Asia, house crows (Corvus splendens) have long flourished in cities, feeding on refuse, nesting in roadside trees, and exploiting the abundance that dense human settlements create. Large-billed crow (Corvus macrorhynchos) have done the same, preferring slightly greener cities. 

That is precisely why their decline matters. Because these crows are not sensitive forest specialists or migratory rarities. They are survivors. If a city becomes inhospitable for them, it signals a deeper transformation in the urban ecosystem — one that affects far more than birds alone.

What changed?

There is no single reason behind the apparent decline of crows in Dhaka. Instead, multiple pressures appear to be converging — each subtle on its own, but powerful together.

Jackdaws demonstrate the intelligence and adaptability of corvids worldwide. But cognitive prowess offers no protection against habitat loss and human intolerance.

The first is habitat loss, even for a species that nests readily in urban trees. Dhaka residences, well into the early 2000s, used to have courtyards and backyard orchards ornamented with mango, mahogany, and rain trees. There were vast wetlands in all directions beyond what was then Dhaka proper. 

But these spaces have gradually vanished. Road widening, flyovers, real estate development, and "beautification" projects often prioritise clean lines over canopy cover. Tree pruning frequently occurs during nesting seasons, destroying nests and discouraging return. For example, the place where I live has fewer than ten trees, all sickly and spindle-shaped, within a 500-meter radius.

Dhaka residences, well into the early 2000s, used to have courtyards and backyard orchards adorned with mango, mahogany, and rain trees. There were vast wetlands in all directions beyond what was then Dhaka proper. But these spaces have gradually vanished. Crows may tolerate cities, but they still need places to roost and breed. When those disappear, so do the birds.

Crows may tolerate cities, but they still need places to roost and breed. When those disappear, so do the birds.

The second pressure is food — both its availability and its quality. Dhaka's waste landscape has transformed rapidly. Open dumps and exposed garbage, once abundant feeding grounds for crows, are increasingly replaced by centralised covered bins, compaction systems, and faster waste removal strategies. While this represents progress in public hygiene, it also removes a key food source for urban scavengers.

At the same time, what remains accessible is often dangerous. Plastic, chemical waste, medical refuse, and contaminated scraps now dominate urban garbage. Crows ingest these materials directly or indirectly, exposing them to toxins that affect survival and reproduction.

Air pollution and heat stress add another layer. Dhaka regularly ranks among the world's most polluted cities. Fine particulate matter affects birds just as it affects humans, impairing respiratory systems and reducing lifespan. Rising urban temperatures—amplified by concrete, traffic, and shrinking green spaces—make conditions even harsher for nesting birds.

Finally, there is human intolerance. As cities become more sanitised and controlled, animals that do not fit neatly into planned urban life are pushed out. Crows are widely perceived as dirty, noisy, or aggressive. Deterrents, deliberate nest removal, and occasional persecution reflect a broader trend: cities increasingly allow space only for carefully curated nature. A few weeks ago, a pair of large-billed crows stopped over for a few days in a neem and a jackfruit tree beside my house. Their deep cawing was met with disgruntled echoes from my neighbours. Some even suggested shooing them away.

The cost of absence

In ecological terms, crows are scavengers that perform a quiet service. They dispose of organic waste, remove carcasses, and recycle nutrients. In social terms, they are woven into memory, language, and daily life. In Dhaka, they were once everywhere.

What makes the crow's disappearance striking is not just ecological loss, but cultural erasure.

Older residents recall evenings when thousands of crows gathered in communal roosts, darkening trees and filling the air with raucous sound. Rickshaw pullers remember feeding scraps to birds at roadside stalls. Building caretakers speak of rooftops once claimed by nesting pairs.

These are not scientific surveys, yet they are meaningful. Ecologists recognise the importance of "social memory" — the collective recollection of how landscapes once looked and sounded. People may not count birds, but they remember when the noise stopped.

The disappearance of crows is not just about losing a familiar bird. It reflects a broader pattern of urban ecological simplification — cities becoming hostile to unscripted life.

When urban ecosystems lose resilience, they become more fragile, less capable of absorbing shocks. Perhaps most importantly, the loss signals a narrowing of what cities are allowed to be. A city without crows may appear cleaner, quieter, more controlled — but it is also less alive, much like the Giant's Garden Oscar Wilde told us about. 

Not extinct but not indestructible

It is important to be precise. Crows have not vanished entirely from Dhaka. They are still seen near markets, riverbanks, and less manicured neighborhoods. But their uneven distribution itself tells a story. Where trees remain, where waste is accessible, where disturbance is lower, crows persist. Elsewhere, silence spreads.

Rooks form massive communal roosts at dusk—a scene older Dhaka residents remember vividly, when thousands of house crows darkened trees and filled the air with raucous calls.

This pattern is not unique to Dhaka. The Hawaiian crow went extinct in the wild in 2002 — victims of habitat loss, predation by introduced species, and disease. They survive only in captivity. The red-billed chough disappeared from much of the UK as traditional livestock grazing declined, eliminating the short grasslands where they fed on invertebrates. In both cases, the decline was gradual, noticed too late.

Without systematic urban bird monitoring, the full scale of the decline remains undocumented. That absence of data is itself telling. Urban biodiversity, especially common species, rarely receives attention until it is already gone.

Globally, researchers warn that cities risk becoming biological deserts, hosting only a few adaptable species while excluding the rest. Dhaka, one of the fastest-growing megacities in the world, sits at the frontline of this transformation.

Listening to the silence

The story of Dhaka's disappearing crows is not about nostalgia. Crows were never particularly loved. They were tolerated, joked about, occasionally chased away. Yet they endured, adapting to the chaos of urban life with remarkable success. Their decline suggests that Dhaka is changing faster, harder, and more ruthlessly than we realise.

Cities are often measured by what they build — roads, towers, flyovers. But they should also be judged by what they lose. When a bird that once defined the soundscape fades away, it demands reflection. I remember Kigali, with its incredible biodiversity and the loud morning calls of the Hadada Ibises. My colleagues and I started calling them "alarm birds." But Dhaka's biological alarm is going silent. The question is whether we are truly caring.