Enzyme polymorphisms in the House Sparrow, Passer domesticus

Methods are described for the visualization of 20 enzymes from the house sparrow, Passer domesticus, in starch gels and by iso-electric focussing. Many of the methods are applicable to other avian species. Two samples of sparrows from the east midlands of England have been analysed. The patterns that are manifest in the gels can be ascribed to between 33 and 35 loci, of which the same nine are polymorphic in both samples. The level of heterozygosity in these birds is about 15%, which at first sight is higher than an introduced population in Australia. However, this difference disappears when homologous loci are compared.     

How Consistently are Good Parents Good Parents? Repeatability of Parental Care in the House Sparrow,Passer domesticus

In many avian species, substantial individual variation occurs in parental food‐provisioning levels, which often is assumed to reflect variation in parental quality. Parental quality also has often been invoked as a key element in mate choice among biparental species, and many sexually‐selected traits have been investigated as potential predictors of parental quality. In recent studies of house sparrow (Passer domesticus) parents, we found that individuals behaved remarkably consistently across time, regardless of temporary manipulations of the nestling provisioning of their partners. This suggests that variation in parental competence may be attributable to quality differences among individuals. One prediction of the ‘parental quality differences’ hypothesis is that individuals also should show consistency in their provisioning behavior across broods. To test this, we compared the parental delivery rates of individual house sparrows across broods. Parents of both sexes reduced their per‐chick delivery rates as the season progressed; parents of both sexes were also responsive to changes in their brood sizes. Despite these sources of environmental variation in provisioning rates, the parental care of individual males was highly repeatable across broods. By contrast, female parental care showed extremely low repeatability, and standardized measures of among‐individual variation in parental behavior revealed females to be much less variable than males. These results indicate that females in this multi‐brooded species have much to gain from mate‐choice decisions predicated on male parental quality or accurate indicators of such, whereas males are less likely to profit from being highly selective about the ‘parental quality’ of their partners.     

The spread of the House Sparrow Passer domesticus in Bolivia

Bolivia lies within the Tropics and contains extremes from desert to jungle and from low to high altitudes. House Sparrows entered the south of Bolivia from Argentina about 1930 and have now spread to towns and villages scattered through about half of the country. These are principally in the semi-arid Andean descents of south and central Bolivia and in the lowlands in Santa Cruz city and certain nearby towns. In the high altiplano they have reached only two cities and are not numerous in either. They appear to be absent from the humid Andean slopes and from most of the eastern and northern lowlands, with the exception of two isolated towns which they could have reached either from Brazil or from elsewhere in Bolivia. House Sparrows do not occur away from human settlements in Bolivia.     

The breeding biology of the House Sparrow Passer domesticus at Blantyre,Malawi

Nhlane, M.E.D. 2000. The breeding biology of the House Sparrow Passer domesticus at Blantyre, Malawi. Ostrich 71 (1 & 2): 80–82.

The breeding biology of the House Sparrow Passer domesticus was studied from 1989–1990. The birds bred throughout the year at this site. Modal clutch size varied from three to four eggs, with a mean clutch of 3.9. The average incubation period was 11.5 days, and the fledgling period 15.4 days. The clutch size of the House Sparrow varied seasonally and was larger from November to June, and smaller from July to October. Chick mortality at Chikunda was attributed to starvation, abandonment, predation, low birth weight, accidental deaths and parasitism.     

云南普洱发现家麻雀

<正>2014年10月,在云南省普洱市思茅区、宁洱县等地多次发现集群的家麻雀(Passer domesticus),雌雄混群。雄鸟羽色与麻雀(P.montanus)相似,眼先、颏、喉部黑色,颊部灰白色,后颈部和颈侧栗褐色,翅上具两道淡色翼斑,下体棕白色。但家麻雀的雄鸟额部、头顶及枕部灰色,耳部无黑色斑块,上胸部黑色,与麻雀明显不同。     

Parental Feeding Rates in the House Sparrow,Passer domesticus: Are Larger‐Badged Males Better Fathers?

Elaborated secondary sexual characteristics may reflect genetic quality or good health, either of which may be associated with an individual's competence as a parent. We examined whether female house sparrows (Passer domesticus) paired to large vs. small‐badged mates gain benefits in the form of increased parental care or improved nestling welfare. House sparrow nests where the male had been trapped and banded were observed for 1 h on at least 5 d during the peak growth period of nestlings. Male feeding shares, measured as the proportion of total feeds per chick made by the male, were marginally positively correlated with male badge size. Moreover, higher male shares of nestling feeding were associated with improved prospects for offspring survival, and a greater proportion of chicks fledged from the nests of larger‐badged males. These results suggest that females paired to large‐badged males gain direct benefits in the form of enhanced nestling survival, which presumably stem from factors associated with increases in the proportion of nestling feeding contributed by their mates.     

Size and trends of the House Sparrow Passer domesticus population in Great Britain

House Sparrow Passer domesticus populations have declined throughout Europe over the last two to three decades; this is of particular concern in urban areas. We analysed data from extensive census schemes organized by the British Trust for Ornithology to determine the current population size of the House Sparrow in Britain, and to assess long-term patterns of change, both in the wider countryside and in urban environments. The national breeding population of House Sparrows was estimated at approximately 13 million individuals (95% confidence interval, 11.9–14.8 million), or about six million pairs. Most of these occur in southeast England and densities are greatest in suburban and rural garden habitats. Overall, populations in rural areas have declined by 47% since the mid 1970s, whereas those in urban and suburban areas have declined by about 60%. Changes in farming practices are likely to account for at least some of the decline in the wider countryside, probably related to changes in food resources, with a loss of grain in fields and more secure storage of harvested grain, though these changes are unquantified. In urban areas, there was an earlier period of decline in the first half of the 20th century due to the loss of horse-drawn transport and generally cleaner streets. The overall national decline since the 1970s masks much heterogeneity in trend among regional populations, and evidence suggests that population processes in the House Sparrow may be relatively fine-grained.     

Uropygial gland size,feather holes and moult performance in the House Sparrow Passer domesticus

Feather holes represent damage to the plumage of birds and are correlated with delayed moult. Uropygial gland size is negatively correlated with feather holes. Consequently, it was predicted that birds with smaller uropygial glands would have more feather holes, and that this would affect moult performance. I examined this prediction in the House Sparrow Passer domesticus. Individuals with smaller uropygial glands had more feather holes, and those with more feather holes moulted later and faster. Therefore, uropygial gland size seemed to affect moult performance via its effect on feather holes. Uropygial gland size may have a positive effect on plumage quality, through a negative effect on feather holes, and therefore on moult timing and speed.     

Interrelation between moulting and breeding in a tropical population of the House Sparrow Passer domesticus

Under the tropical regime in Rajkot, India, the House Sparrow Passer domesticus had a prolonged breeding season, so that breeding and moulting of the primaries overlapped. The moult was interrupted commonly in the nesting birds and was observed more frequently in females than in males. It is concluded that moult initiation was not controlled by reproductive hormones in any way. It is also suggested that the reproductive hormones may not be directly involved with moult interruption.     

Brood size and body condition in the House Sparrow Passer domesticus: the influence of brooding behaviour

In many bird species, females undergo a marked decline in body condition during the first days of the nestling period. This decline may be because brooding young chicks reduces the time available for foraging. Alternatively, it might be viewed as an adaptive way to reduce flight costs when the food demand of the brood is highest. To test these hypotheses we modified the brooding commitment of House Sparrows Passer domesticus by manipulating brood size to see if changes in time spent brooding affects adult body condition. During the nestling period, females provided on average three times as much brooding as males. Reduced broods received 14% more brooding than large broods and time spent brooding declined with brood size and chick age according to an exponential decay function. Male body condition was unaffected by brood size and remained stable throughout the reproductive period. Body condition of females with enlarged broods decreased gradually during the nestling period, whereas that of females tending reduced broods dropped abruptly and significantly upon hatching. This resulted in females with reduced broods having lower body condition during the first half of the nestling period than those with enlarged broods. The sharp drop in body condition of females with reduced broods coincided with the period that brooding was most intensive. Indeed, female body condition at the end of the nestling period was negatively correlated with the proportion of time they spent brooding during the first half of the nestling period. Thus, the probable lower homeothermic capacities of reduced broods implies a higher brooding commitment for female House Sparrows that, in turn, may reduce their opportunity to forage and consequently also their body condition.     

新疆阜康地区家麻雀的巢址选择

2013年7月和2014年5~7月,在新疆阜康地区对家麻雀(Passer domesticus)的巢址选择进行调查,以分析影响家麻雀巢址选择的生态因子。在研究区内共找到75个家麻雀的自然巢,筑巢生境为农田和防护林带,均在白杨(Populus adenopoda)林和胡杨(P.euphratica)林中的树上筑巢。其中,繁殖成功巢40个,繁殖失败巢20个,15个巢未记录到繁殖结果。在研究区内的居民房屋、墙洞等没有发现家麻雀的巢。采用逻辑斯蒂回归和主成分分析方法对筑巢地海拔(m)、筑巢树种、筑巢树高(m)、巢距路距离(m)、巢距地面高度(m)、巢上方盖度(%)、筑巢树胸径(m)、最近邻巢的距离(m)这些家麻雀的主要巢址参数进行分析,结果表明,影响新疆阜康地区家麻雀巢址利用的主要因素为巢距地面高度(m)、巢上方盖度(%)和巢距路距离(m)。对家麻雀繁殖成功巢(n=40)和繁殖失败巢(n=20)的巢址参数进行比较,两者差异不显著,因而推测,在研究区域的尺度内,家麻雀的巢址选择并不是影响其繁殖成效的主要因素。     

Changes in the House Sparrow Passer domesticus population in Valencia (Spain) from 1998 to 2008

Capsule The population of House Sparrow Passer domesticus has experienced a sharp decline in the municipality of Valencia.

Aims To investigate the population trends of House Sparrows.

Methods Between September 1998 and December 2008, House Sparrows were censused monthly in 22 urban parks covering a total of 118 ha. Additionally, birds in the wider urban landscape were censused in 24 plots of about 50 ha during the winter and spring of years 1998, 2003 and 2007.

Results The House Sparrow population experienced a significant decline of about 70% over 10 years in urban parks, with monthly peak values decreasing from about 2000 birds in 1998 to about 500 in 2008. Between 1998 and 2007, a significant decline was detected in the urban landscape mostly during the winter.

Conclusions Urban parks are a main feeding habitat for House Sparrows, and habitat structure of urban parks has remained similar throughout these years. Therefore, the decreasing number of sparrows recorded in parks probably reflects an overall population decline of the species in Valencia. This decline has coincided with high‐intensity urban development i.e. an increase in the building density and a reduction in the amount of wastelands and other feeding habitats. Thus, shortage of nest‐sites did not seem to be a limiting factor for the population, but a reduction of food availability may be partially responsible for the observed patterns.     

Providing chicks with extra food lowers male but not female provisioning in the House Sparrow Passer domesticus

We assessed whether adult House Sparrows Passer domesticus adjusted their provisioning in response to an experimental increase in the nutritional condition of their nestlings. When we supplemented chicks directly with additional food, male parents, but not female parents, reduced their provisioning. The results for males, but not females, run contrary to a previous experiment in this species. In addition, female provisioning was positively associated with both brood size and the age of the brood. In contrast, whereas male provisioning was positively associated with brood size, males did not increase provisioning as their chicks grew older. Males, but not females, exhibited repeatability in their provisioning. Food supplementation had a larger positive effect upon nestling survival in smaller broods than in larger broods. Overall, there appear to be fundamental differences between males and females in how decisions regarding the level of parental investment in the current brood are made.     

Morphometric differentiation across House Sparrow Passer domesticus populations in Finland in comparison with the neutral expectation for divergence

To understand the biology of organisms it is important to take into account the evolutionary forces that have acted on their constituent populations. Neutral genetic variation is often assumed to reflect variation in quantitative traits under selection, though with even low neutral divergence there can be substantial differentiation in quantitative genetic variation associated with locally adapted phenotypes. To study the relative roles of natural selection and genetic drift in shaping phenotypic variation, the levels of quantitative divergence based on phenotypes (P_ST) and neutral genetic divergence (F_ST) can be compared. Such a comparison was made between 10 populations of Finnish House Sparrows (n = 238 individuals) collected in 2009 across the whole country. Phenotypic variation in tarsus‐length, wing‐length, bill‐depth, bill‐length and body mass were considered and 13 polymorphic microsatellite loci were analysed to quantify neutral genetic variation. Calculations of P_ST were based on Markov‐Chain Monte Carlo Bayesian estimates of phenotypic variances across and within populations. The robustness of the conclusions of the P_ST–F_ST comparison was evaluated by varying the proportion of variation due to additive genetic effects within and across populations. Our results suggest that body mass is under directional selection, whereas the divergence in other traits does not differ from neutral expectations. These findings suggest candidate traits for considering gene‐based studies of local adaptation. The recognition of locally adapted populations may be of value in the conservation of this declining species.     

Risk‐taking and survival in the House Sparrow Passer domesticus: are plumage ornaments costly?

An important cost of sexual and social colour signals may be increased conspicuousness of the animals to visual predators. Although such predation costs have repeatedly been proposed for various ornaments of birds, especially for melanised and depigmented signals with low presumed production costs, tests of this hypothesis are rare and inconclusive. In this study we investigated whether individual variation in plumage ornamentation was associated with predator-related risk-taking behaviour and short-term survival in free-living House Sparrows Passer domesticus . In a large sample of birds we measured three aspects of coloration used in sexual and social signalling: the size of the melanised black throat patch in males, and the area and conspicuousness of the depigmented wing-bar in both sexes. We measured risk-taking by manipulating the distance of feeders from shelters, and recorded individually ringed birds feeding close to and far from shelter. Sparrows seemed to perceive the farther feeders as more risky, as indicated by the shorter time spent and smaller groups feeding far from rather than close to shelter. However, the use of the more risky (farther) feeders was not related to any of the colour traits we measured, suggesting that Sparrows do not adjust their risk-taking behaviour to their ornamentation. Males (the more ornamented sex) did not take less risk than females. Furthermore, we found no evidence that larger throat patches or more ornamented wing-bars reduced the probability of survival. Our findings were robust and consistent across multiple approaches, even when we controlled for several potential confounding effects. These results do not support the suggestion that melanised and depigmented plumage ornaments have significant predation costs in House Sparrows.     

Blood and Tissue Protozoa of the English Sparrow (Passer domesticus domesticus) in Galveston,Texas*

SYNOPSIS. The 42% incidence of Plasmodium in blood films of English sparrows reported here is the highest on record for surveys of blood parasites of birds in the United States. The only Plasmodium species identified in the sparrows was P. relictum. Adult birds were almost universally infected and tended to experience the highest degree of parasitemia in the spring months, while young birds had a higher blood positivity in the summer months. The lowest incidence of Plasmodium positive blood films occurred in fall and winter in the Galveston area. Overwintering birds had a decrease in parasitemia corresponding to reported minimal gonadal activity in sparrows. The 20% incidence of Lankesterella (avian Toxoplasma) in the blood of these sparrows was also higher than has been reported in other blood film surveys in this country. Incidence of this parasite in blood films was highest in the summer months, corresponding with highest average temperature for the year. Lankesterella could be found in 95% of sparrows whose tissues were examined after autopsy. Ducks and pigeons in the immediate vicinity of the survey sparrows had neither Plasmodium nor Lankesterella in blood films. Resident wild birds from adjacent rural areas, including redwinged blackbirds, boat-tailed grackles, laughing gulls and meadowlarks, had fewer Plasmodium and Lankesterella than the sparrows. A few Lankesterella were found in the liver or spleen of young redwinged blackbirds, and only 2 of 79 wild birds had the organisms in their heart blood. Plasmodium was found only in meadowlarks and included P. hexamerium and elongatum as well as relictum.     

Individual and Sex Differences in Habituation and Neophobia in House Sparrows (Passer domesticus)

Heterogeneity in the environment favours foragers that are flexible (phenotypically plastic). However, consistent individual differences in behaviour (personality), such as in risk‐taking, might affect an individual's ability to find food, avoid predators and adjust to new conditions. It is now well known that personalities exist in many taxa, but much less is known about individual variation in plasticity. We measured the tendency to begin foraging across different levels of risk in house sparrows (Passer domesticus), using a behavioural reaction norm framework to simultaneously assess personality and plasticity. We asked whether individuals were consistently different across risk levels, and whether they differed in habituation and neophobia, both of which were treated as cases of plasticity. We found that males habituated more than females by beginning to feed sooner after repeated instances of a human disturbance in the presence of an initially unfamiliar object. Individuals of both sexes also exhibited consistent differences across trials, but did not differ in the rate of habituation beyond the difference between the sexes. When a novel object was placed in the foraging area, both sexes exhibited similar degrees of neophobia by delaying feeding. The magnitude of this change varied among birds, indicating individual differences in neophobia. Our results indicate that both personality and individual variation in plasticity exist but should be treated as independent phenomena. The presence of variation in plasticity implies that the raw material necessary for selection on neophobia exists, and that if heritable, plasticity in risk‐taking across contexts could evolve.