The house sparrow (Passer domesticus) is one of the most widespread and abundant bird species in the world. However, there has been a dramatic decline in house sparrow populations in parts of its range, especially in Europe and North America. This has led some people to believe that the house sparrow is becoming rare. But is this really the case?
Quick Facts on House Sparrows
- The house sparrow is native to Eurasia and North Africa, but has been introduced widely around the world.
- They live in close association with humans, especially in urban and suburban areas.
- House sparrows are very gregarious birds that nest colonially and forage in flocks.
- They are considered one of the most familiar and common birds worldwide.
So while the house sparrow is an abundant and successful species overall, local declines in certain areas have made some people question if they are truly as common as they once were. Below we go into more detail on the status and population trends of the house sparrow worldwide and in specific regions.
Global Population and Conservation Status
The house sparrow has an extremely large global range and population size. The latest estimates indicate there are between 529-581 million individual house sparrows worldwide (BirdLife International 2016). They are found on every continent except Antarctica, inhabiting a broad range of habitat types in both rural and urban areas.
Due to their huge global population and extremely large range, the house sparrow is evaluated as Least Concern on the IUCN Red List of Threatened Species (BirdLife International 2016). Species listed as Least Concern are not currently considered at risk of extinction. So from a global perspective, the house sparrow remains widespread and abundant, and not rare.
However, the IUCN Red List classifies the house sparrow as Decreasing in Europe and North America, meaning populations are declining in those parts of its range. But the species is stable or even increasing in other regions like Eastern Europe, parts of Asia, Africa, and South America (Summers-Smith 2003).
House Sparrow Global Population Trends
| Region | Population Trend |
|---|---|
| Global | Stable |
| Europe | Declining |
| Eastern Europe | Stable/Increasing |
| North America | Declining |
| Asia | Stable/Increasing |
| Africa | Stable/Increasing |
| South America | Increasing |
So in summary, while house sparrow populations have decreased in parts of their native range like Western Europe and North America, globally the species remains widespread, abundant, and not rare. Declines in certain regions do not necessarily reflect the overall global population status.
House Sparrow Status in Europe and North America
The house sparrow originated in the Middle East and spread with agriculture into Europe and North Asia. It was later introduced to North America and other parts of the world. But in parts of its native European range, house sparrow populations have declined significantly, especially since the 1980s. Surveys in European countries like the UK, Netherlands, Belgium, and Germany have reported population declines from 30-60% in recent decades (De Laet and Summers-Smith 2007).
In North America, house sparrows were introduced on multiple occasions from Europe in the 1800s. Populations expanded rapidly as the species adapted well to human settlements. However, as in Europe, North American populations have declined since the 1980s. Breeding Bird Survey (BBS) data from 1966-2015 shows declines of 60-75% in house sparrow populations (Sauer et al 2017).
Parts of their range in South America, Africa, and Asia have remained stable or even increased in recent decades. So the population declines seem to be concentrated in Europe and North America where the house sparrow has lived the longest in association with human habitats.
Causes of House Sparrow Declines in Europe and North America
The exact causes behind the decline in house sparrow numbers across parts of its native range are not fully understood. But a variety of factors likely play a role:
- Changes in agriculture and land use – The shift to industrialized farming and loss of mixed farming has reduced food availability in rural areas.
- Urbanization – Declining vegetative cover and increased pollution levels in cities may reduce habitat quality.
- Buildings and infrastructure changes – Modern architecture offers fewer nesting sites and less shelter.
- Predation – Increased predator populations impact sparrows especially where vegetation cover has decreased.
- Disease – West Nile Virus, avian malaria, and other diseases may contribute to mortality.
- Competition – Introduced birds like house finches may compete for food and nest sites.
- Climate change – Changing weather patterns and temperatures likely add physiological stress.
The combined effects of these factors over decades have led to substantial declines in house sparrow numbers across many parts of Europe and North America. However, global populations remain robust for this adaptable species.
House Sparrow Status in the United Kingdom
The United Kingdom is home to around 5.3 million breeding pairs of house sparrows as of 2015 (British Trust for Ornithology). However, widespread population declines have been reported in the UK since the 1970s:
- House sparrow populations declined by 71% between 1977 and 2008 (Robinson et al 2005).
- Between 1994-2000, surveys showed a 20% reduction in range (British Trust for Ornithology).
- House sparrows are now absent from many town and city centers.
- Declines are most pronounced in southeast England, with reductions up to 90% in London (De Laet and Summers-Smith 2007).
House sparrow declines in British cities are attributed to modern architecture providing fewer nesting places, busy roads, lack of food sources like insects and grains, predation, disease, and air pollution.
Despite major declines in southeast England and some urban areas, house sparrow populations remain relatively abundant and stable in most of Scotland, Wales, southwest England and Northern Ireland. The species is not considered threatened or rare throughout most of its UK range. But localized extinctions in parts of southeastern England are signs this familiar bird has declined more than any other widespread UK bird species.
House Sparrow Population Trends in the United Kingdom
| Region | Population Trend |
|---|---|
| UK Overall | Declining from 1970s-2000s but stable recently |
| Southeast England | Severely declining, up to 90% decreases in and around London |
| Southwest England | Stable or increasing |
| Northern England/Scotland | Stable or increasing |
| Wales | Stable or increasing |
| Northern Ireland | Stable or increasing |
House Sparrow Status in the United States
The house sparrow was introduced to North America from Europe in the mid-1800s. It spread rapidly across the continent and became one of the most abundant and familiar backyard birds. But as in the UK, American populations have declined substantially since the 1980s.
Breeding Bird Survey (BBS) data indicates house sparrows in the continental US declined by 57% between 1980 and 2016 (Sauer et al 2017). Christmas Bird Count (CBC) data shows a similar decrease of 59% over roughly the same period (National Audubon Society 2010).
However, as in parts of Europe, declines have not been uniform across North America:
- Midwestern states saw the largest population declines, with states like Illinois down 72% (BBS data).
- West coast states like California had smaller declines around 30% (BBS data).
- Southeastern states like Florida had relatively stable populations with no significant change (CBC data).
So house sparrow numbers vary across different regions but remain relatively common through most of their US range. The species is not considered rare or threatened over most of the American portion of its global range.
House Sparrow Population Trends in the United States
| Region | Population Trend |
|---|---|
| Overall US | Declining by 50-60% from 1980s-2000s |
| Midwest | Largest declines, over 70% decrease in some states |
| Northeast | Moderate declines of 50-60% |
| Southeast | Stable to moderate declines around 30% |
| West | Smaller declines around 30% |
Is the House Sparrow Rare?
In summary, while the house sparrow has experienced significant population declines in parts of its native European and North American range since the 1980s, globally it remains one of the most widespread and abundant bird species in the world.
Key points:
- The global house sparrow population is estimated at 529-581 million individuals.
- They remain common and widespread across most of Europe and North America despite regional declines.
- House sparrows are stable or increasing in many parts of Asia, Africa, South America, and Australia where they have been introduced.
- They are classified as Least Concern by the IUCN due to their huge global population.
So while the house sparrow has become less common in areas where it has undergone steep declines, it continues to maintain an extremely large global population and range size. The species is not currently considered globally rare, threatened, or at risk of extinction.
However, the significant population crashes reported in parts of Europe and North America over the last few decades warrant continued monitoring of house sparrow numbers. Conservation efforts focused on providing suitable nesting habitat in cities, reducing pesticide use, and increasing food availability could help reverse these regional declines.
Conclusion
The house sparrow remains one of the most ubiquitous bird species around the world. While it has faced declines across portions of its native range, global populations are large and stable enough that the house sparrow is not considered rare or immediately threatened. However, the causes behind the localized decreases in European and North American house sparrow numbers require more research and highlight the need to better understand population dynamics in once-common species.
