The subject of the disappearance of House Sparrows from urban areas
has caught the imagination of the Indian bird-loving public. In the
absence of any worthwhile surveys to measure population changes, the
so called decline in sparrows remains a hypothetical question at best.
Here K.S. Gopi Sundar, one of India's foremost writers on
ornithological subjects, and an honorary Advisor to our website,
examines the issues related to the hype with science as a tool
and species conservation in India
K.S. Gopi Sundar
March 20 was declared the World
House Sparrow Day. Conservationists got together for the occasion with
a powerful political leader presided over the ceremonies. The
organisations involved ranged from the prestigious Cornell University
Laboratory to the founder-organisation of the sparrow movement, Nature
Forever Society of Mumbai.
The event of course begged several questions, the first of which is of
course why sparrows? The answer is long-winded, but a fascinating
tale. In this article I explore this and other core questions related
to how information in the media may not have the backing of real
science, but why populist events like the Sparrow Day are important
The House Sparrow is a widely recognized species wherever it occurs.
Its Latin name, Passer domesticus, and its common English name are
both reminiscent of their close relationship with humans for a very
long time. The darker male with its black bib and the dull female are
among the first birds children in cities and villages learn to
identify. In the United Kingdom, long-term counts being carried out in
several locations by volunteers led to a rather alarming conclusion -
the common House Sparrow was declining in numbers. The erstwhile very
common bird entered the Red List of UK’s endangered species for the
first time in 2002. These results, published in peer-reviewed journals
as is required for science, showed that declines were as much as 68%
overall and over 90% in urban areas, and the bird disappeared from the
famous Kensington Gardens in central London.
In urban areas, a range of reasons for the decline were posited for
the decline. These included predation by urban cats and crows,
reduction in hedges and gardens that sparrows may breed in, and lack
of food especially insects that are important to raise young birds.
These results widely publicised by the media inspired Mohammed Dilawar
from Mumbai to take some action in India. A lecturer by profession, he
took up the cause of the sparrows in Mumbai single-handedly. Dilawar
believes that sparrows in Mumbai have declined, and assists hundreds
of sparrows by feeding them, putting out water, and setting up and
selling bird-houses to ensure that they can nest safely. Many many
bird-houses later, Dilawar was honoured by TIME Magazine as a Hero of
the Environment in
2008. His continued efforts led to the declaration of the World House
The tale of the commonplace sparrow is not all gloom-and-doom as much
of the popular media reports would have us believe. Dr. Denis
Summer-Smith in the UK has been working on sparrows since 1947, and
has written a considerable amount on their decline. Much of what I
will write here is based on his observations and writings. Sparrow
decline in rural England tracked mechanisation, increased use of
chemicals, and intensification. Between the 1970s and 1990s, sparrows
in UK’s farmlands declined , but have been stable since. Sparrow
declines in urban areas were most drastic in central London, but much
smaller in sub-urban areas and smaller towns.
In London, sparrows declined most after 1920 immediately after the
horse-drawn carriages were replaced by the motor-car. Spillage of
grain and even undigested grain in horse droppings provided food for
sparrows, which diminished greatly when motorised vehicles took over.
The next rapid decline was recorded between 1996 and 2001 for reasons
not yet entirely clear. In smaller urban centres, no decline of
sparrows was apparent, and may have been due to sparrows from farm
areas moving in. Dr. Robinson and colleagues from the British Trust
for Ornithology calculated that there were 13.2 million sparrows
during the breeding season in Britain in 2005. To complicate matters,
volunteer counts conducted between 1994 and 2000 all over Europe
showed that while sparrows declined marginally overall in this period,
they actually increased in Scotland and Wales.
So why should sparrows decline so much only in a few urbanised areas
of UK? Cats and crows are found everywhere, so cannot explain this
imbalanced decline. Sparrows are found even in areas without bushes
and hedges, and in some places with hedges where monitoring has been
long-term, sparrows have disappeared.
The one hypothesis that is gaining traction is the reduced insect
foods theory. Simon Bower in Hamburg, Vincent Peach in Leicester, and
van der Poel from Amsterdam, to name a few of the scientists, have
demonstrated that nestling starvation early in the nesting season is
the reason for fewer chicks surviving. Compelling evidence of lowered
survival leading to declines in the overall population comes from a
thorough study by Siriwardena and colleagues published in the
prestigious ornithological journal IBIS. It currently appears that
multiple factors are working to reduce the sparrow populations in
Europe and UK – locations where scientific attention on the species
has been relatively considerable.
The trend is not one of simple decline everywhere, and a direct answer
to their decline in central London continues to evade us. A £5,000
reward offered ten years ago by the British newspaper, The
Independent, for a study that provides a scientific explanation for
the sparrows’ decline remains unclaimed.
In contrast to the UK, scientific information on sparrows in India is
meagre. A study of sparrows in 2008 in Bangalore by Rajshekar and
Venkatesha of Bangalore University showed that areas with more foods
for the birds had more sparrows. In the absence of previous
information, they could not infer if the population had declined.
My surveys in Uttar Pradesh’s farmland areas in 2008-09 show the house
sparrow to be the second most
numerous bird species in the winter next only to the cattle egret – an
extremely common waterbird found throughout India. Densities varied
between 26 and 164 sparrows per square kilometre; this means that in
Uttar Pradesh alone there are still lakhs of House Sparrows.
Dr. Neeraj Khera and her students in TERI University carried out a
study in Delhi in 2007 and found more sparrows in areas with more
green cover, but do not know where and to what extent declines of
sparrows have occurred in the city. There simply is no previous data
to say so. Sparrow densities in Delhi varied from 5 to 45 individual
sparrows per square kilometre; meaning that they number in the
thousands, at the very least, in the city.
Anecdotal observations in the popular media indicate that sparrows in
Delhi, Bangalore and few other cities are declining. Careful watchers,
however, maintain that numbers of sparrows in these cities had fallen
earlier this decade, but appears to be on the rise once again. The
simple fact is we do not know enough to state one way or the other.
Statements in the popular press, however, would give a drastically
different view of the sparrow – that they are in imminent decline and
about to vanish.
Cats, cell-phone towers, declining vegetation in cities, and new style
of housing are cited as being responsible for drastic declines in
sparrow numbers. These views are simply not substantiated by actual
studies, or the meager information we have on their numbers. House
Sparrows are actually invasive to many countries and are thriving
there at the cost of local species making people from these countries
wonder why sparrows need celebratory attention, but that is another
So what does one make of events like the World House Sparrow Day and
the unsubstantiated doom-and-gloom statements that are provided to
journalists? These are two very different but important questions.
Given current governmental plans of development in the country, the
decline in the state of our environment is imminent. Any action
therefore meant to raise awareness about any species should be
welcome. If one were to consider just birds, there is amazingly little
known of the 1200 or so species that grace India. Even large species
like the Great Indian Bustard, possibly the heaviest flying bird in
India and one that is reputed to be declining precipitously, have
received meager attention. The Bustard inhabits valuable grasslands
and can serve to understand an entire ecosystem that both humans and a
wide range of wild species are dependent on.
We can pick 3-4 species to celebrate each day, as Dilawar has done for
the house sparrow, and cover all 1200 species in one year. The actual
day for each species is not really important, and neither is there a
necessity to fly into Delhi to celebrate each species. If anything
this exercise should serve to reinforce how little we know of each
L. Shyamal, an active editor of bird accounts on Wikipedia, laments on
this fact each time he picks a species to update. Many Indian bird
species whose accounts he has updated don’t even have basic
information like the incubation period, let alone long-term population
information with which to conclusively infer the reasons for their
current status. For many species, where some information is present,
it is from old British records that may or may not have relevance
today. Hopefully, increased awareness about our collective ignorance
will lead to focused work that fills in these lacunae. This new
information can in turn hopefully lead to identification of real
problems, and species that require assistance on a priority basis
given that financial resources and skill sets for
these are limited.
Events like the house sparrow day also lead to active associations of
conservation activists, conservation biologists, and political
leaders. These interactions are imperative to ensure that findings of
scientists and conservation biologists are taken seriously by
activists and law-makers, and to create independent channels of
communication among them.
The second question of unsubstantiated statements is more serious.
Statements like that make it appear that there is good and thoroughly
verifiable information available. This is unfortunate on more than one
count. It has the real danger of directing resources to species and
issues that perhaps don’t really require it immediately, relative to
species and issues that require immediate attention. It undermines
efforts of people like Dilawar who are attempting to ensure increased
awareness where there was none. It also undermines efforts of other
scientists and science-based organisations who aim to provide
authoritative information based on serious science – usually taking
many years to discover even simple patterns. Finally, and most
seriously, they provide the risk of scientific findings not being
considered valid for intervention in policy and conservation.
As Karl Popper the statistician stated, our knowledge can only be
finite while our ignorance must necessarily be infinite. Accepting
that there is a lack of information only serves to empower new
questions and new students to seek answers. Even after decades of
work, Summers-Smith writes that it is necessary to determine the
correct cause for the sparrows’ status before providing commentary.
Even “confirmed sparrow lovers” like him “should retain a sense of
proportion and not be moved solely by our emotions”.
Fortunately for Dilawar and the house sparrows, the situation in India
is not yet dire for these well known feathered friends. There remains a
huge amount to be discovered about sparrows, and about bird
populations in India. There is fortunately a growing pool of
responsible, well-trained young conservation biologists in the
country. I feel optimistic that events like the World House Sparrow
Day will increase and be powered by real science and verifiable
information to the benefit of birds and humans alike.
From The house sparrow: by
an ornithologist, J. H. Gurney
K. S. Gopi Sundar
Citation: Sundar, KSG. 2010. The
New Indian Express, (Zeitgeist Suppl.), 10 Jul 2010, pg. 6
Also read the Blog
Post by Sumit Sen on the same subject
Please send comments/corrections to: