The Mystery Of The Disappearing Sparrow

7th August 2009

The House Sparrow is dismissed as an uninspiring little bird by twitchers, and often not much regarded by the wider population either. Now it’s becoming apparent that the population is falling, however, sentiments may be softening. Jack Watkins investigates.

There’s a horrible story about Chairman Mao, the former Chinese supremo, ordering his people into collective action to rid the country of sparrows – pests who, feeding in huge flocks, were depleting corn stocks. A directive was issued for each peasant to keep banging and shouting to deter the birds from landing, until they eventually fell from the sky, dead from exhaustion. It sounds pitiful, although we should perhaps remember that rural house sparrows were widely persecuted in Britain once, for similar reasons.

We may pride ourselves that we are a nation of bird lovers, but house sparrows are seldom in the vanguard of those we wax lyrical about. This is, after all, a bird whose ‘song’ consists of unrhythmical cheeps and chirrups, and whose coat is a dusty mix of browns and greys. When you have a party of them in residence near you, they do indeed seem to be everywhere, in and out of bushes, hanging around in noisy, argumentative gangs on the tops of fences, and raiding the bird feeders. They are cute enough, certainly, and lend a buzz to any garden, but no-one gasps at the sight of a house sparrow. In fact, it was even policy for a time for serious birders to ignore them, with bird ringers encouraged by the British Trust for Ornithology (BTO) not to ring any more of them.

It’s a human trait that it is only when we lose – or seem to be on the point of losing – something, that we begin to recognise its value, and in recent years, the realisation that all is not well with the house sparrow has brought a change of heart. When the species was fully included in the Common Birds Census for the first time, in 1976 it became apparent that what had seemed like a massive population was actually in serious decline. Since then the evidence has been of a further substantial drop, with latest figures suggesting numbers are 63% down from the BTO’s first Garden Bird Feeding survey in 1979.

It’s the usual thing when talking about falling bird numbers to point the finger of blame at intensive agriculture, and it’s certainly true that the ‘country sparrow’ has taken a knock, thanks to pesticides which mean fewer invertebrates to feed the young in the chick-rearing period, and the switch from spring to autumn sowing, which reduces available seeds.

But house sparrows are, as we are so well aware, creatures of the urbs and suburbs too. Could it be that Joe Public is as much to blame as Farmer Giles? For the last 20 years, people have been busily paving over once-attractive front gardens to make space for their cars. TV ‘home improvement’ programmes have made decking a fashionable convenience. Proud gardeners often manicure their plots to within an inch of their lives, dead-heading vigorously, sweeping up twigs and leaves, making sure there are no unsightly heaps of compost or patches of long grass, and going to battle against weed and insect pests with an army of sprays and pellets. A tidy back garden is a pleasing human aesthetic, but it’s made it hell out there for the birds.

Young Male Sparrow

The BTO has recently been carrying out a study of sparrows in urbanised landscapes, using volunteers drawn from its weekly Garden Birdwatch survey. Mike Toms, the head of Garden Ecology at the BTO, says that, although the research brings us closer to understanding the causes of House Sparrow decline, we still do not have the definitive answer. Part of the difficulty is that there appear to be a number of different factors involved: traffic pollution, increased levels of predation and competition with Collared Doves, for example, may all have played a role. What the research does make clear, however, is that opportunities within gardens for both feeding and nesting are important, and that the loss of nest sites to new building regulations, together with that decline in the availability of invertebrate food sources, have played a part in the sparrow's demise.

Part of the difficulty in getting a complete understanding of the causes of decline is that there appear to be a number of different factors involved. Traffic pollution, increased levels of predation and competition with Collared Doves may also have played a role.

Modelling work, carried out by the BTO, has also highlighted the impact of 'garden-grabbing', where houses with large gardens are demolished and replaced by high-density housing. The BTO's work suggests that sparrows are soon lost if an area is developed in this manner. One traditional feature of built-up areas that has been undergoing a happy revival lately, though, has been the allotment, but even with this there are dangers, believes Mike. “Allotments have often proved useful feeding habitats for sparrows, usually with neglected areas of weeds and vegetation that can provide cover. Hopefully, the droves of ‘Good Life’ devotees now joining the allotment revolution won’t make the land too tidy.”

Of course, if you have a flock of sparrows nesting near you, you will wonder what all the fuss is about. Sparrows are sedentary, and seldom stray more than a kilometre from their natal area. They often live in ‘communities’ of a hundred birds or more. In comparison with other species, the population of sparrows is indeed still large – something like 12 million of them in the breeding season. But all the evidence shows numbers are down and still falling. This is sad and yet there is hope. Half the population lives in urban areas, which makes us all somehow implicated in their decline… but it may also mean that, by moderating our behaviour or the way in which we manage our properties, we can also contribute to their revival.

For more details on the BTO’s campaign to save the House Sparrow,
visit www.bto.org or call 01842 750050.
A 96 page book – Gardening for Birdwatchers, by Mike Toms, Ian & Barley Wilson, published by the BTO – gives advice on improving gardens for birds.

Find Your Local