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"The
house sparrow, once more cockney than the cockneys,
is now a rarity in London"
(Tony Blair, 2000)
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Download
this Action Plan in full
1. Aims
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Raise
awareness of the need for biodiversity conservation
by focussing attention on the decline in the house sparrow
and its importance as a cultural emblem. |
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Establish
the cause(s) of decline in the population of house sparrows
and, if possible, undertake measures to reverse the
decline. |
2. Introduction
Until about ten years ago, the house sparrow (Passer
domesticus) was one of the commonest birds in London
and was one of the most numerous and regular visitors to
garden bird tables. The 'Cockney sparrer' has always been
a firm favourite with Londoners, reflecting its lively social
behaviour and relatively tame nature. In Hudson's day, sparrows
had been present by the thousand in the parks of central
London. However, on 10 September 2000, a London Natural
History Society 'Bird Walk' around Hyde Park and Kensington
Gardens failed to find a single one.
The house sparrow's distribution is related to the pattern
of human settlement. As a native species it extends from
North Africa, throughout Europe and Central Asia and northwards
beyond the Arctic Circle. It has also become established
in a number of other countries as a result of introduction
by man.
House sparrows have traditionally taken bread and scraps
from garden bird tables as well as the seeds of flowers
in parks and gardens, wastelands or road and railside land.
When feeding young, insects such as aphids and caterpillars
are a more important part of its diet.
The birds nest mainly in buildings · in roofs, cracks and
crevices · or amongst creepers on walls and sometimes in
dense shrubbery or trees. Under good conditions, sparrows
can raise up to five broods per year, although two or three
is more typical.
The house sparrow is generally regarded as sedentary, although
some local movements occur. In rural areas, the birds traditionally
move off to the cornfields after the end of the breeding
season. Seasonal changes in London indicate similar dispersal,
probably in search of autumn seed (Baker 1987).
3.
Current Status
There is much evidence that this once abundant bird has
declined dramatically in recent years · as outlined below.
It is now common knowledge that house sparrows have disappeared,
or become far less common, in many places where they were
formerly abundant. This applies both in the centre of London
and many of the suburbs, as well as some of the surrounding
towns and indeed a number of cities in other parts of the
country such as Bristol and Edinburgh. For many years, the
house sparrow received rather little attention from the
scientific community. It seemed to be so common, its survival
could be taken for granted. Very few observers have maintained
records over a long time scale, and these have usually been
as part of more general bird monitoring programmes. Some
of this data is now proving invaluable in tracing the species'
decline.
The issue has attracted media attention and frequent inquiries
from the general public. On 1 December 1997 a question was
put in the House of Lords "Whether there has been
a reduction in the numbers of sparrows in London; if so,
to what is this reduction attributed?" The Independent
(15.5.00) offered a £5,000 reward to anyone who could solve
the mystery of the disappearing house sparrow.
3.2.1 Surveys based on London or
other cities
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A
series of late autumn bird counts has been carried out
in Kensington Gardens, dating back to the 1920s (Nicholson
1995). In 1925, 2,603 birds were recorded, but by 1948
the count had fallen to 885; this first decline has
been attributed to the withdrawal of horse-drawn traffic,
with its associated grain supply. For the next 20-30
years, the records suggest a continuing although less
clear-cut decline, but then a far sharper decline from
544 birds in 1975 to just 81 in 1995, indicating a fall
of around 85% at some time between 1975 and 1995. Just
8 birds were recorded in the October 2000 autumn bird
count. |
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A
survey of house sparrows in gardens has been carried
out by Helen Baker of the London Natural History Society
since 1995, based upon weekly counts. The general trend
is for a decrease in flock size, fewer gardens with
ten or more fledglings and an increase in the number
of gardens where no fledglings or indeed no sparrows
at all have been seen. |
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A
recent study at Wimbledon Park in south-west London
by Dave Dawson, based on 'Standard Walk' methodology,
has documented a 95% decline in the birds since 1989.
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A
decline of almost 98% has been observed in suburban
Glasgow, from 4.9 birds/ha in 1959 to less than 0.1
per ha in 1997 (Summers-Smith 1999). A recent lack of
large foraging flocks on ripening grain fields in late
summer has been noted. |
3.2.2 Evidence from national surveys
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The
BTO Garden Bird Feeding Survey shows that the average
number of house sparrows has fallen by about 50% between
1978 and 1993. Though this is a substantial decrease,
it is considerably smaller than the decline observed
in Kensington Gardens, Wimbledon Park and suburban Glasgow.
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The
RSPB Wildlife Explorers Big Garden Birdwatch, which
requires children to report on birds in their garden
each year in January, shows a 50% decline in house sparrow
numbers since 1979, when the survey began. |
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The
National Breeding Birds Survey shows a statistically
significant decline of 7% between 1994 and 1998. Within
London, the BBS decline has been more substantial, with
a fall of about 50% between 1994-1999. When the survey
began in 1994 the house sparrow was the most numerous
species in the London samples. By 1999 it had been overtaken
by feral rock dove, wood pigeon and starling. However,
there are evidently still some pockets with high numbers,
especially in north-east London. |
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House
sparrow declines have been recorded from many other
countries in western Europe, including Scandinavia,
Netherlands, Belgium, Germany and Austria, although
good numbers are still reported by casual observers
visiting Paris and some other parts of France.
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4. Specific
Factors Affecting the Species
A number of factors have been put forward to account for
the observed changes in the sparrow population. It is not
yet been possible to identify what is causing the decline,
although there are several theories. Some of the factors
outlined below could have significant impacts in particular
localities and it is possible that they are acting in combination.
Research is needed to try to identify the most important
factors · only then will it be possible to put in place
any effective remedial measures. A variety of factors other
than those outlined below could be involved.
4.1 Factors relating
to food supply
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Reduction
in insect food supply for the young: A
study in Hamburg has blamed a lack of aphids in early
spring for a lack of breeding success in house sparrows
in that city. (Mitschke et al, 2000). A decline
in the availability of invertebrates (such as aphids)
for feeding young is also suggested as a major factor
in house sparrow decline by Summers-Smith (1999).
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Impact
of lead-free petrol on aphids:
There is a theory that lead free petrol might contain
chemicals which reduce the supply of aphids (Summers-Smith,
2000). |
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Changes
in agricultural practice: These
may affect the London house sparrow population especially
in late summer/autumn, when birds leave their nesting
territories in residential areas and move off in seed-feeding
flocks. No doubt some London birds disperse into the
surrounding countryside. At this time, changes in agricultural
practice such as the switch to autumn sowing of cereals
and lack of stubble as autumn and winter feeding habitat
may have some impact. Additionally, if the London population
has traditionally been augmented from time to time by
surplus birds from nearby rural populations, a fall
in breeding success in rural populations could reduce
the number of immigrants into London. |
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Reduction
in seed supply in autumn: In
both central London and the suburbs, there has been
a marked reduction in wasteland in recent decades, as
it is developed more quickly. |
4.2 Predation
Another theory relates to the recent increase in sparrowhawk
and magpie numbers. A single species of predator is normally
only likely to act as a major factor in population control
of a given prey species if it is a broad-based predator,
able to turn to other food supplies as a favoured prey species
declines in response to predation pressure. Another significant
predator is the domestic cat, and its numbers are of course
not limited in the same way by natural population regulation.
However, no evidence of a significant increase in the domestic
cat population has been forthcoming.
4.3 Disease
Declines on this scale have, in some other species, been
attributed to disease. A virus or Salmonella infection
has been suggested. However, few, if any, diseased birds
have been observed in this country, although any corpses
would most probably be quickly disposed of by carrion-feeders.
It is possible that if the birds are already weakened by
a disease of some sort, they become more susceptible to
predation. If so, an increase in the population of a given
predator could have a greater impact on its prey.
4.4 Changes
relating to availability of nest sites
Changes in roof design may be an issue in some areas of
older housing undergoing renovation, as modern roof repairs
may prevent access to the roof space for birds. However,
a decline has also been noted in areas where roof replacement
is less widespread.
In addition to re-construction, roofs are often subject
to pesticide treatment. Whilst it is recognised that certain
pesticides are harmful to bats, no such issue has been recognised
for birds.
4.5 Pest control
Although the house sparrow is still recognised as a pest
species in some quarters and may be controlled legally (see
below), there is not thought to be an appreciable amount
of control undertaken in London at present.
5. Current
Action
5.1 Legal status
The house sparrow is still classified as a pest species
in relation to the Wildlife & Countryside Act (1981,
as amended). It was originally listed as a bird that may
be controlled at any time of year, but is now covered by
legislation that provides for an annually reviewed general
licence to control a specified list of pest species, with
the land owner's consent (Statutory Instrument no 3010 1992).
5.2 Mechanisms targeting the species
These current actions are ongoing.
They need to be supported and continued in addition to the
new action listed under Section 7.
5.2.1 Survey and research
A number of on-going surveys have been summarised above
under section 3. Contract work has been commissioned by
DETR and The Independent newspaper's campaign ahs offered
a £5,000 'reward'. In the spring and summer of 2000, the
RSPB ran a survey on House sparrow nesting behaviour amongst
its Wildlife Explorers (youth section), which investigated
the relationship between nesting frequency and the age of
houses, plus the location of nest sites and use of nest
boxes. London Wildlife Trust's garden survey for 2000/1
includes data on House sparrows.
6.
Objectives, Actions and Targets
Most of these actions are specific
to this species. However, there are other, broader actions
that apply generically to a number of habitats and species.
These are located in a separate 'Generic
Action' section which should be read in conjunction
with this document. There are generic actions for Site Management,
Habitat Protection, Species Protection, Ecological Monitoring,
Biological Records, Communications and Funding.
Please note that the partners
identified in the tables are those that have been involved
in the process of forming the plan. It is not an exclusive
list and new partners are both welcomed and needed. The
leads identified are responsible for co-ordinating the actions
· but are not necessarily implementers.
Objective 1 To understand the key factor(s) affecting the
population and distribution of house sparrows in London
through the completion of fundamental scientific research
Target: To have the results of scientifically valid research
to explain the decline by 2010
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Action
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Target Date
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Lead
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Other Partners
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Collate existing research
information of the status of house sparrows and possible
causes of decline, with emphasis on
urban areas.
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e="A
2001
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GLA
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Identify the key issues which should
be investigated in the research projects
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2001
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GLA
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LWT, LNHS,
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Establish links with other relevant
research projects.
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2001
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GLA
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As a preliminary experiment, investigate
the effect of increasing the availability of nest
boxes on local populations through a small scale,
controlled study.
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2003
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LWT
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GLA
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Fund and commission fundamental research
into each of the key issues identified above
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2010
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GLA
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LWT, LNHS
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Review progress and outcome of other
research projects on house sparrow decline annually
and draw on the results of this review to revise the
proposed actions if necessary.
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Annually
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GLA
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Objective 2 To involve people in London and raise awareness
of house sparrows
Target : Commission, complete and evaluate survey by the
end of 2003
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Action
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Target Date
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Lead
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Other Partners
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Draw up proposal for survey of house
sparrow population and distribution in London involving
public participation
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2001
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GLA
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LWT, LNHS, LA
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Commission survey, evaluate and publicise
results
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2005
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GLA
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LWT, LNHS, LA
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Relevant Action Plans
London
Plans
Gardens, Wasteland; Farmland;
Parks, Amenity Grasslands and City Squares.
National Plans
Cereal Field Margins; Ancient
and/or Species Rich Hedgerows; Urban Habitat Statement.
Key References
Heidj, CJ (1985). Comparative
ecology of the House Sparrow, Passer domesticus, in rural,
suburban and urban situations. Thesis, Vriji Universiteit
te Amsterdam.
Mitschke, A., Rathje, H. &
Baumung, S. (2000). House sparrows in Hamburg: population,
habitat choice and threats. Hamburg State Ornithological
Protection Station. Hamburger Avifauna Beitr. 30.
Summers-Smith, J.D (1999).
Current status of the House Sparrow in Britain. British
Wildlife, 10: 381-386.
Summers-Smith, JD (2000). The
Independent 11th September 2000.
Abbreviations
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GLA - Greater London
Authority
LA · Local Authorities
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LWT - London Wildlife
Trust
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Contact
The Lead for this species is
the Greater London Authority.
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Jan Hewlett
Strategy Directorate
GLA
Romney House
Marsham St
London SW1P 3PY
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Tel 020 7983 4329
Email [email protected]
web www.london.gov.uk
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St James' Park, 1986 © David Goode
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