House Sparrow Population Research Articles

Population of House Sparrow Passer domesticus (Linnaeus, 1758) in Three Different Habitats of the Tarai Arc in Kumaun Region, Uttarakhand, India

The present study was carried out to determine the population of House Sparrow in three different habitats of the tarai arc in Kumaun region, Uttarakhand for a period of one year. The monthly field visits were carried out from August 2018 to July 2019 at different locations of three habitats viz. agricultural area, urban area and forest area. The findings of the present survey revealed that the agricultural areas enjoy highest number of individuals and relative abundance (525, 56.21%) followed by urban area (316, 33.83%) and least in forest area (93, 9.95%), respectively. In terms of seasonal variations, the maximum individuals were observed during winter season (November to February, 63%) followed by summer season (March to June, 29%) and lowest in rainy season (July to October, 8%). The study also indicated a significant difference between the numbers of House Sparrow observed among the three different habitats. While comparing the number of House Sparrow during the investigation in three habitats it was observed that number of species were less in forest habitat whereas the highest numbers were recorded in and around agricultural areas which could be due to availability of reasonable nesting sites in traditional dwellings of farmers and availability of food.

Differential Long-Term Population Responses of Two Closely Related Human-Associated Sparrow Species with Respect to Urbanization

Urban planning and management need long-term population level studies for evaluating how urbanization influences biodiversity. Firstly, we reviewed the current population trends of the House Sparrow (Passer domesticus) and the Eurasian Tree Sparrow (Passer montanus) in Europe, and evaluated the usefulness of citizens’ science projects to monitor these species in Finland. Secondly, we conducted a long-term (1991–2020) winter field study in 31 urban settlements along a 950 km north–south extent in Finland to study how latitude, weather and urbanization influence on sparrow’s growth rates. The House Sparrow is declining in 15 countries, and increasing in 5, whereas the Eurasian Tree Sparrow is declining in 12 and increasing in 9 European countries. The trend of the House Sparrow was significantly negative in continental Europe. However, the trend of the Eurasian Tree Sparrow was not significant. Both species have declined simultaneously in six countries, whereas in four countries, their trends are opposite. Citizen-based, long-term (2006–2020) winter season project data indicated that House Sparrow has decreased, whereas Eurasian Tree Sparrow has increased in Finland. However, the short-term (2013–2020) breeding season citizen-based project data did not indicate significant changes in the occupation rate of sparrows. Our long-term (1991–2020) field study indicated that wintering populations of the House Sparrow have decreased, whereas the Eurasian Tree Sparrows have both expanded their wintering range and increased their population size. Based on our winter count data, latitude and weather did not significantly influence the growth rates of sparrows. When the human population increased within the study plot, House Sparrow populations decreased, and vice versa. There was also a trend that a decreasing number of feeding sites has decreased the House Sparrow numbers. Urban-related factors did not influence the growth rate of the Eurasian Tree Sparrow. Our results indicate that the colonization of a new, even closely related species does not influence negatively on earlier urbanized species. It is probable that the niches of these sparrow species are different enough for allowing them to co-occur. The House Sparrow mainly nests on buildings, whereas the Eurasian Tree Sparrow can easily accept, e.g., nest boxes. Urban planning should take care of both the food availability and nest sites availability for both sparrow species.

Marginal-covert moult in the House Sparrow Passer domesticus

ABSTRACT Marginal coverts are often neglected in passerine moult studies due to their small size and large number. Here, we document eight moult components of this group of wing coverts in a House Sparrow population from Barcelona in 2018–21: timing, growth rate, intensity, speed, duration, sequence, extent and barb density. We also tested the influence of various intrinsic and extrinsic factors on marginal-covert moult. Our adult population started marginal-covert moult on 29 July and finished it on 29 August, with the moult of hatch-year birds delayed 13 days in relation to the moult of adults. Growth rate of the largest marginal covert increased significantly with its size but did not differ between sexes. Intensity of marginal-covert moult replacement was not constant during the moult progress, which took 32 days on average. Moult sequence of marginal coverts started with the proximal feathers, proceeded distally replacing the central rows and was completed toward the front and rear rows. Moult extent was complete except in one case. Size of the largest marginal covert increased with calamus width, but not significantly, and barb density decreased with feather size, but not significantly, and neither measure differed between sexes. Comparison with published results indicated that growth rate is lower in marginal coverts than in primaries and rectrices, whereas barb density is greater. Linear regression of marginal-covert size on both growth rate and barb density can be used to predict growth rate and barb density of flight feathers in the House Sparrow.

Population flux of the house sparrow Passer domesticus Linnaeus 1758 in Chinnamanur town, Uthamapalayam taluk of Theni district, Tamil Nadu, India

A thorough study of house sparrow behaviour and its population is essential to revive its population status which is the need of the hour. Therefore, the nature of sparrow population, their nests, water and food sources, interspecific competitions and noise pollution were taken into consideration in the present investigation, which documented its first research carried at Chinnamanur town, Uthamapalayam taluk of Theni district, Tamil Nadu, India. The study period was divided into summer and winter seasons and the survey was carried out for a period of nine months from April 2019 to December 2019 by point count and ebird data method. A total of 542 house sparrows were counted of which 250 was present in summer and 292 in winter. The overall house sparrow population in Chinnamanur town, related to the summer and winter seasons exhibited the range of correlation coefficient value to be 0.94 indicating a very strong positive correlation. Above all, the present study revealed that mobile phone towers were not the main reason for the decline of house sparrows, rather it was loss of habitat and food, urbanization, noise pollution, interspecific competition and conversion of agricultural lands into plots.

Population, Nesting, and Conservation Issues of House Sparrow <i>Passer domesticus</i> (Linn., 1758) in Rural Arakkonam, Vellore District, Tamil Nadu, India

Population, Nesting, and Conservation Issues of House Sparrow <i>Passer domesticus</i> (Linn., 1758) in Rural Arakkonam, Vellore District, Tamil Nadu, India

First Evidence of a Relationship Between Female Major Histocompatibility Complex Diversity and Eggshell Bacteria in House Sparrows (Passer domesticus)

Bacteria are known to exert positive and negative influences on animals’ health and fitness. Bacteria, in particular those inhabiting the skin and inner organs of vertebrates, are horizontally or vertically transmitted. Specifically, mothers of bird species can transfer bacterial strains to their offspring when the egg is passing the reproductive tract, as the eggshell rubs against the wall of the uterus. In this context, the female immune system might play an important role in influencing the vertical transmission of bacteria. Here, we investigate the relationship between the major histocompatibility complex (MHC) and cultivable eggshell bacteria originating putatively from the female urogenital tract in a captive population of house sparrows (Passer domesticus). We predict that females with a more variable MHC will transfer fewer bacteria onto the eggshells. Our results show a negative relationship between the number of functional MHC class I alleles and bacteria originating in the urinary tract and growing on a selective medium. This is the first study to find a correlation between female MHC diversity and eggshell bacteria.

Urban House Sparrow (Passer domesticus) populations decline in North America

House Sparrow (Passer domesticus) populations declined across much of their global range in the late 20th century. Most research examining this decline is conducted in the species' native European range, but Europe encompasses a small portion of the species' current distribution. House Sparrow population trends in the United States and Canada, and the potential mechanisms driving these trends, remain relatively unexplored. We use 21 years of data from Project FeederWatch, a large-scale citizen science project, to investigate House Sparrow population trends in North America. We found winter flocks in urbanized areas were larger than flocks in rural areas, with widespread spatial heterogeneity in local population trends. Despite greater abundance in developed areas, House Sparrow populations declined in developed areas from 1995 to 2016 while remaining stable in rural areas. House Sparrow population declines coincide with an increase in populations and expansion of the winter distributions of Accipiter hawks, which are known predators of House Sparrows. However, we do not find a direct connection between the presence of Accipiter hawks at count sites and House Sparrow population declines in winter. These results expand our knowledge of widespread House Sparrow declines to North America and provide context for continuing research on House Sparrow declines in the introduced range.

Investigating temporal and spatial correlates of the sharp decline of an urban exploiter bird in a large European city

Increasing urbanisation and human pressure on lands have huge impacts on biodiversity. Some species, known as “urban exploiters”, manage to expand in urban landscapes, relying on human resources. The House Sparrow (Passer domesticus) is the perfect example of a human-commensal species. Surprisingly, this urban exploiter has been declining all over Europe over the past decades. The proximate causes of this decline remain poorly understood. We particularly lack understanding about urban habitat characteristics that are particularly unfavourable for House Sparrows. In the present study, we analysed fine-scale habitat characteristics of House Sparrow population sizes and trends using a fifteen-year House Sparrow census (2003–2017) covering the urban diversity of Paris (nearly 200 census sites), one of the densest European cities. We documented for the first time the dramatic decline (−89%) of the species in Paris over the study period. The temporal decline over the whole city correlates with the concomitant increase in the number of breeding Sparrowhawks. We could not detect statistical influences of annual variations in weather conditions and pollution. The decline of House Sparrows is spatially heterogeneous. Indeed, site-scale analyses revealed sharpest declines at sites that initially hosted the largest numbers of sparrows, which are areas with a relatively high proportion of green spaces and new buildings. Further experimental studies are now needed to disentangle the exact impact of specific characteristics of the urban environment on House Sparrow populations.

Physiological and morphological correlates of blood parasite infection in urban and non-urban house sparrow populations.

In the last decade, house sparrow populations have shown a general decline, especially in cities. Avian malaria has been recently suggested as one of the potential causes of this decline, and its detrimental effects could be exacerbated in urban habitats. It was initially thought that avian malaria parasites would not have large negative effects on wild birds because of their long co-evolution with their hosts. However, it is now well-documented that they can have detrimental effects at both the primo- and chronical infection stages. In this study, we examined avian malaria infection and its physiological and morphological consequences in four populations of wild house sparrows (2 urban and 2 rural). We did not find any relationship between the proportions of infected individuals and the urbanisation score calculated for our populations. However, we observed that the proportion of infected individuals increased during the course of the season, and that juveniles were less infected than adults. We did not detect a strong effect of malaria infection on physiological, morphological and condition indexes. Complex parasite dynamics and the presence of confounding factors could have masked the potential effects of infection. Thus, longitudinal and experimental studies are needed to understand the evolutionary ecology of this very common, but still poorly understood, wild bird parasite.

Wild Bird Survey and Damage Estimation for Some Field Crops at Giza Governorate, Egypt حصر أنواع الطیورالبریة وتقدیر أضرارها لبعض المحاصیل فی محافظة الجیزة - مصر

About 470 bird species known from Egypt. The majority are non-breeding migrants, passing through the country, exploiting the wide range of habitat types unique for their life, including agricultural habitats. A survey of wild bird carried out in three agricultural districts, El-Badrasheen, El-Aayyat and El-Hawamdiah districts, in Giza Governorate, from March 2018 to February 2020, using the point transect method. Twenty-eight species belonging to nine orders and twenty-five families recorded. House sparrow (passer domesticus niloticus) and Hooded Crow (Corvus corone cornix) were the only recorded noxious species, damaging wheat and corn crops. House sparrow damage to wheat start after the first week of the panicles emergence causing 21.4 % and 19 % losses, with the highest loss rate of 5.7 and 6.1% during 1st of April at El-Badrasheen and El-Aayyat districts, respectively. The damage percent were 16.3 and 14.5% to corn by hooded crow in both districts from the 1st week of August up to the 2nd week of September and the highest loss rate were 5.4 and 4.2% during the 4th week of August in the two districts, respectively. It is advisable to apply damage control programs against house sparrow populations at the beginning of February in wheat fields, and against hooded crow populations at the beginning of June in corn fields in these areas.

Numbers of invasive House Sparrows Passer domesticus in a rural landscape of Limpopo province, South Africa

The House Sparrow Passer domesticus is recognised as one of the commonest avian invasive species globally, with its occurrence associated with human existence. However, relatively little on population sizes of this species in rural landscapes has been documented. The study on House Sparrows was conducted in three areas in a rural landscape of Limpopo province, South Africa where it is an invasive, to 1) determine population numbers of the House Sparrow between the years 2014 and 2016, and 2) investigate the interaction between the number of House Sparrows and the number of their active nests. The House Sparrow population numbers showed no significant differences between 2014, 2015 and 2016. The House Sparrow numbers were influenced by the number of active nests in 2014 and 2016. The current study showed that the presence of House Sparrows was not affected by the house type they roosted in, and the number of active nests was not influenced by the house types available in each area. The results also showed that the House Sparrow occurs across a rural landscape with variation in numbers across seasons. The evidence reported provides significant insight into how invasive House Sparrows are well established in rural landscapes around human habitation, and it is recommended that this should be incorporated into the management of such alien invasive birds.

Multi-generational genetic consequences of reinforcement in a bird metapopulation

Translocation of conspecific individuals to reduce extinction risk of small, isolated populations and prevent genetic depletion is a powerful tool in conservation biology. An important question is how the translocated individuals influence the long-term genetic composition of the recipient population. Here, we experimentally reinforced a house sparrow (Passer domesticus) population, and examined the impact of this translocation on allele frequencies, levels of heterozygosity and genetic differentiation over six cohorts. We found no permanent increase in the mean number of alleles across loci or levels of observed heterozygosity, but a few alleles private to the translocated individuals remained in the population and we found a short-term increase in heterozygosity. Consequently, genetic differentiation of the recipient population compared to the genetic composition prior to reinforcement was small. The limited genetic impact was due to combined effects of a small probability of establishment and low mating success for the translocated individuals, together with increased genetic drift in the recipient population. Our findings emphasize the importance of selection and genetic drift as forces that may decrease the genetic contribution of reinforcement, especially in small populations. Conservation managers should aim to improve habitat quality in the recipient population to reduce genetic drift following translocation and thereby avoid the need for continued reinforcement. Furthermore, by facilitating establishment success and selecting individuals expected to have high mating success, possibly indicated by sexually selected traits, genetic contribution of released individuals is increased which in turn will decrease reproductive skew and genetic drift.

Epigenetic Potential in Native and Introduced Populations of House Sparrows (Passer domesticus).

Epigenetic potential, defined as the capacity for epigenetically-mediated phenotypic plasticity, may play an important role during range expansions. During range expansions, populations may encounter relatively novel challenges while experiencing lower genetic diversity. Phenotypic plasticity via epigenetic potential might be selectively advantageous at the time of initial introduction or during spread into new areas, enabling introduced organisms to cope rapidly with novel challenges. Here, we asked whether one form of epigenetic potential (i.e., the abundance of CpG sites) in three microbial surveillance genes: Toll-like receptors (TLRs) 1B (TLR1B), 2A (TLR2A), and 4 (TLR4) varied between native and introduced house sparrows (Passer domesticus). Using an opportunistic approach based on samples collected from sparrow populations around the world, we found that introduced birds had more CpG sites in TLR2A and TLR4, but not TLR1B, than native ones. Introduced birds also lost more CpG sites in TLR1B, gained more CpG sites in TLR2A, and lost fewer CpG sites in TLR4 compared to native birds. These results were not driven by differences in genetic diversity or population genetic structure, and many CpG sites fell within predicted transcription factor binding sites (TFBS), with losses and gains of CpG sites altering predicted TFBS. Although we lacked statistical power to conduct the most rigorous possible analyses, these results suggest that epigenetic potential may play a role in house sparrow range expansions, but additional work will be critical to elucidating how epigenetic potential affects gene expression and hence phenotypic plasticity at the individual, population, and species levels.

From Africa to Europe: evidence of transmission of a tropical Plasmodium lineage in Spanish populations of house sparrows

BackgroundAvian malaria parasites are a highly diverse group that commonly infect birds and have deleterious effects on their hosts. Some parasite lineages are geographically widespread and infect many host species in many regions. Bird migration, natural dispersal, invasive species and human-mediated introductions into areas where competent insect vectors are present, are probably the main drivers of the current distribution of avian malaria parasites.MethodsA total of 412 and 2588 wild house sparrows (Passer domesticus) were captured in 2012 and 2013 in two areas of the Iberian Peninsula (central and southern Spain, respectively). Genomic DNA was extracted from blood samples; parasite lineages were sequenced and identified by comparing with GenBank and/or MalAvi databases.ResultsThirteen Plasmodium lineages were identified in house sparrows corresponding to three major clades. Five individuals were infected by the African Plasmodium lineage PAGRI02, which has been proposed to actively circulate only in Africa.ConclusionsDespite the low prevalence of PAGRI02 in sparrows in Spain, our results suggest that the area of transmission of this parasite is more widespread than previously thought and covers both Africa and Europe. Further studies of the global distribution of Plasmodium lineages infecting wild birds are required to identify the current transmission areas of these parasites. This is vital given the current scenario of global change that is providing new opportunities for avian malaria transmission into areas where parasites were previously absent.

Genetic admixture despite ecological segregation in a North African sparrow hybrid zone (Aves, Passeriformes, Passer domesticus×Passer hispaniolensis).

Under different environmental conditions, hybridization between the same species might result in different patterns of genetic admixture. Particularly, species pairs with large distribution ranges and long evolutionary history may have experienced several independent hybridization events over time in different zones of overlap. In birds, the diverse hybrid populations of the house sparrow (Passer domesticus) and the Spanish sparrow (Passer hispaniolensis) provide a striking example. Throughout their range of sympatry, these two species do not regularly interbreed; however, a stabilized hybrid form (Passer italiae) exists on the Italian Peninsula and on several Mediterranean islands. The spatial distribution pattern on the Eurasian continent strongly contrasts the situation in North Africa, where house sparrows and Spanish sparrows occur in close vicinity of phenotypically intermediate populations across a broad mosaic hybrid zone. In this study, we investigate patterns of divergence and admixture among the two parental species, stabilized and nonstabilized hybrid populations in Italy and Algeria based on a mitochondrial marker, a sex chromosomal marker, and 12 microsatellite loci. In Algeria, despite strong spatial and temporal separation of urban early‐breeding house sparrows and hybrids and rural late‐breeding Spanish sparrows, we found strong genetic admixture of mitochondrial and nuclear markers across all study populations and phenotypes. That pattern of admixture in the North African hybrid zone is strikingly different from i) the Iberian area of sympatry where we observed only weak asymmetrical introgression of Spanish sparrow nuclear alleles into local house sparrow populations and ii) the very homogenous Italian sparrow population where the mitogenome of one parent (P. domesticus) and the Z‐chromosomal marker of the other parent (P. hispaniolensis) are fixed. The North African sparrow hybrids provide a further example of enhanced hybridization along with recent urbanization and anthropogenic land‐use changes in a mosaic landscape.

Avian malaria-mediated population decline of a widespread iconic bird species.

Parasites have the capacity to affect animal populations by modifying host survival, and it is increasingly recognized that infectious disease can negatively impact biodiversity. Populations of the house sparrow (Passer domesticus) have declined in many European towns and cities, but the causes of these declines remain unclear. We investigated associations between parasite infection and house sparrow demography across suburban London where sparrow abundance has declined by 71% since 1995. Plasmodium relictum infection was found at higher prevalences (averaging 74%) in suburban London house sparrows than previously recorded in any wild bird population in Northern Europe. Survival rates of juvenile and adult sparrows and population growth rate were negatively related to Plasmodium relictum infection intensity. Other parasites were much less prevalent and exhibited no relationship with sparrow survival and no negative relationship with population growth. Low rates of co-infection suggested sparrows were not immunocompromised. Our findings indicate that P. relictum infection may be influencing house sparrow population dynamics in suburban areas. The demographic sensitivity of the house sparrow to P. relictum infection in London might reflect a recent increase in exposure to this parasite.

Measuring Up to Reality: Null Models and Analysis Simulations to Study Parental Coordination Over Provisioning Offspring

Behavioral coordination when provisioning offspring, through alternation and synchrony, has been hypothesized to influence rearing success. However, studying coordination at the pair level presents two analytical difficulties. First, alternating or synchronous (i.e., simultaneous) feeding can occur randomly and be induced by a shared environment. Therefore, a null model must account for this apparent coordination that occurs by chance. Second, alternation and synchrony in provisioning are intrinsically linked to the rate of provisioning itself, and the effects of coordination and provisioning rate, for instance on fitness, need to be distinguished. In this paper, we explore several randomization procedures and simulation scenarios to tease apart true coordination from random alternation and synchrony, and to find an appropriate statistical model for analyzing coordination. First, to establish a baseline of alternated or synchronous visits expected by chance, we took data from a natural population of house sparrows and randomized inter-feeding intervals in various ways. Alternation and synchrony in the observed dataset were higher than expected by chance under any of our randomizations. However, it was impossible to exclude that alternation and synchrony patterns did not arise due to the pair's shared environment. Second, to identify a way of statistically modeling coordination without generating spurious effects due to intrinsic mathematical relationships between coordination and provisioning rates, we simulated data according to different scenarios. Only one out of five candidate models for analyzing alternation was deemed appropriate, and gave similarly appropriate results for analyzing synchrony. This work highlights the importance and difficulty of finding an adequate null model for studying behavioral coordination and other emergent behaviors. In addition, it demonstrates that analyzing simulated data, prior to analyzing empirical data, enables researchers to avoid spurious effects.

Are house sparrow populations limited by the lack of cavities in urbanized landscapes? An experimental test

Current urban policies are associated with deep changes in urban structures, which may impoverish urban biodiversity. A major concern is the disappearance of nesting sites for wild vertebrate species living in urban areas. New urban structures without any cracks or cavities may especially preclude cavity nesters from breeding in cities and they may cause population declines. In that context, we experimentally investigated this question in an urban exploiter bird species (the house sparrow Passer domesticus), which is dramatically declining in most European cities. To test if the lack of cavities is limiting house sparrow populations in urban areas, we equipped 11 sites along an urbanization gradient with nest boxes and we then evaluated the rate of occupancy of these nest‐boxes. This urbanization gradient was characterized by very rural places (isolated farms) and moderately urbanized areas (town of medium size, i.e. 60 000 inhabitants). Surprisingly, rural nest boxes were more occupied than urban ones, suggesting that cavity availability is probably more constraining in rural areas relative to urban ones. Therefore, our study suggests that urban house sparrow populations are probably not constrained by a lack of nesting sites in medium size cities with urban designs similar to our city of interest (Niort, western France). This hypothesis definitely needs now to be tested in further urban landscapes (e.g. large cities and urban landscapes with other architecture and management policies).

Present scenario in respect of House-Sparrows’ depleting trends and conservation efforts in and around Kurukshetra, Haryana, India

The present research work was carried out during 2003 to 2016 to aim the scenario of depleting trends and conservation efforts of House Sparrow in and around Kurukshetra district in Haryana province in India.  House Sparrow Passer domesticus was abundantly available in each and every corner of villages, towns and cities in Haryana and Punjab in early 1990s. Today, it has been totally wiped out from its very popular places of abundance. Its depletion is so alarming that now there is no chirping of House sparrow in early Morning and Evening Hours. The extremely low numbers of House Sparrows are directly linked with whooping failure of its broods and also non-availability of nesting places. Infact, latter is very crucial in diminishing common house sparrow populations across the length and breadth of the Indian Subcontinent. Its restoration is impending. The issue is sensitive and gigantic. Conversely, its restorative measures are apparently simple and straight forward. The present studies argued that dwelling houses should necessarily have Verandas and ventilators with shutters inside of walls. Bushes, Bougainvilleas vines, hedges, beri-plants be grown extensively. In addition, wooden boxes of 9x6” be installed on tree branches and within the premises of every human dwelling in all villages, towns, cities and metropolitan cities across Indian- territory to restore house sparrow’s alarming depleting populations in modern times. House sparrow responds quickly to rejuvenative measures.

Factors affecting the abundance of House Sparrows Passer domesticus in urban areas of southeast of Spain

ABSTRACTCapsule: House Sparrows Passer domesticus in the Valencian Community, where the species is declining, were more abundant in parks and urban areas where rubbish bins are available as a source of food. In heavy traffic areas, crowded streets and high-rise building zones, the species was less abundant.Aims: To explore biotic and abiotic factors affecting the abundance of urban House Sparrows. To infer the causes that might explain the urban decline and to propose measures that might halt it and elevate population numbers.Methods: The abundance of urban House Sparrows was analysed in relation to 17 landscape variables by carrying out 181 point counts (50 urban parks/38 schools/93 streets) per season across six locations and over five seasons (breeding and non-breeding seasons) in southeast Spain. Urban parks were also described by 21 additional variables. Hierarchical partitioning analyses were used to identify favoured or avoided urban factors by birds in each season.Results: House Sparrows were most abundant in parks and other urban areas where rubbish bins were available as their foraging sites. The presence of rubbish bins, area and proximity to other parks favoured their abundance in parks. Furthermore, House Sparrows were less abundant in crowded streets, heavy traffic areas and high-rise buildings zones.Conclusion: House Sparrows were present in high abundance where they feed but were scarce in polluted, crowded and heavily built-up areas of the city. Changes in the structure of these urban habitats may underlie the documented declines across Spain. Green urban planning and management are needed to ensure heterogeneous green areas with enough vegetation coverage to provide high availability of natural food versus anthropogenic food scraps. Sufficient numbers of buildings offering nest sites and reduced air pollution might ameliorate cities adequately to support larger populations of House Sparrows.