Where Did the Sparrows Go?

My grandmother's kitchen had sparrows in it. Not as a metaphor — actual sparrows, in and out through a window that was never closed, nesting in the gap above the door frame where the wood had shrunk away from the wall. They were treated roughly the way you treat a draught: noticed, occasionally complained about, fundamentally accepted.

I cannot remember the last time I saw one in a kitchen. The sparrows did not go somewhere else in any simple sense. They thinned out, in cities, over a couple of decades, and the thinning was gradual enough that most of us only registered it in retrospect.

What makes the house sparrow interesting is that it was never a wilderness species. It is one of a small set of birds that attached itself to human settlement and did extremely well there for a very long time. It did not need forest. It needed the specific texture of the way we used to build: rough surfaces, ledges, gaps under eaves, untidy edges where a nest could go. It needed some part of the ground left unpaved, with insects in it, because sparrow chicks are fed on insects even though the adults eat grain.

Then we changed what a building is. Smooth façades, sealed joints, glass and aluminium, no eaves, no gaps — an aesthetic that reads as clean and is, from a sparrow's point of view, a sheer cliff with nowhere to put anything. At the same time the untidy edges went: the vacant plot became a parking lot, the hedge became a compound wall, the kitchen garden became tiles. Each change was an improvement by the standards being applied. Collectively they removed both the nest site and the food supply for the chicks.

I am wary of single-cause explanations here, and you should be too. Plenty has been proposed — mobile towers, unleaded petrol additives, pesticide use, competition — and the honest position is that the picture is not fully settled and probably differs between cities. But the structural story is hard to argue with: a bird that depended on gaps, and a built environment that has been systematically eliminating gaps.

The useful thing about that framing is that it makes the problem tractable at a scale a person can actually act on. You cannot personally fix a river. You can leave a gap. Nest boxes work, and they work better when they are the right size and put somewhere shaded. A shallow dish of water, changed often enough not to breed mosquitoes, does more than people expect in a hot city. A patch of ground left unpaved, a hedge left slightly unruly, a few native plants that host insects — these are not gestures. They are habitat, in the only form a dense city can offer it.

There is a version of conservation that only counts if it happens somewhere remote and photogenic, and I think it has done real damage to how ordinary people understand their own agency. Most species that are in trouble are in trouble because of cumulative small decisions about ordinary places. That is also where the recovery has to start.

The sparrows did not leave because they wanted wilderness. They left because we stopped building anything they could live in. That is a harder fact than a tragedy, because it implicates design rather than fate — and it means the fix is a design problem too.