A comparative account of calls of common myna in different human-influenced environments

Common Myna (Sturnus tristis, formerly Acridotheres tristis) is one of Australia's most readily identified pest species and have been implicated in the reduction of native fauna. This study aimed to determine the distribution, habitat use and roost site selection of Mynas on the urban fringes of Sydney, New South Wales, Australia, as well as the avian species composition of areas in which Mynas occurred. The information was gathered with a view to estimating the impact of this invasive species on native avifauna. In total 3661 birds were counted in 1349 km of survey transects in western Sydney. Mynas were the most abundant bird recorded in the surveys, and exotic species accounted for 41% of all birds counted, but only 20% of the total number of species. Comparison of distribution data across habitat types suggests that Mynas do not extend far beyond urban habitats, and Mynas were primarily observed in suburban-industrial areas, small suburban reserves or sporting grounds and roadsides in semi-rural areas. Differences in sex-specific size distribution of Mynas occurred in semi-rural and urban areas. Urban areas also contained higher densities of preferred roosting trees with dense canopies, suggesting Myna populations have been aided by historical urban planning and landscaping. Together these data suggest that Mynas are likely to affect urban-dwelling native avifauna and that careful urban planning may reduce their distribution and potentially their impact.

Air pollution can have deleterious impacts on human health and the environment. Historically, air pollution studies have focused more on cities. However, it is also important to consider the impact on large suburban populations living closer to the major cities. In this study, nitrogen oxides (nitrogen dioxide and nitric oxide), sulfur dioxide, ozone, and ammonia concentrations were measured from fifteen sites in the Greater Philadelphia area, Pennsylvania, USA using Ogawa passive samplers from September 2021 to May 2022. The fall season had the highest mean NOx concentrations (11.03 ± 4.51 ppb), and spring had the highest mean O3 concentration (18.65 ± 6.71 ppb) compared to other seasons. NOx concentrations were higher at suburban (30.43 ± 33.79 ppb) and urban sites (22.49 ± 12.54 ppb) compared to semi-rural sites (11.08 ± 9.20 ppb). SO2 was not detected in most of the measurements. The positive statistically significant correlation between NO and NH3 in urban (R2 = 0.33, p-value <0.05) and suburban sites (R2 = 0.37, p-value <0.05) during winter and spring, respectively, suggests a high attribution of traffic emissions to NH3 at urban and suburban sites. Influence of traffic emissions on air pollutant values for the study region is also supported by similar NOx concentrations between suburban and urban sites as well as decreasing NO2/NOx ratios with increased distance from expressways. This study shows that passive sampling can be effectively used for assessing spatial and seasonal variations in air pollutants within an area of diverse land use. Implications: This study presents the findings of temporal and seasonal patterns for nitrogen dioxide, nitric oxide, tropospheric ozone, and ammonia at urban, suburban, and semi-rural areas of the greater Philadelphia region. The main objective of the study is to monitor air pollution in suburban and semi-rural areas which are not monitored for air pollution. We monitored from a total of fifteen sites in three seasons to assess air pollution in suburban and semi-rural areas near the major city in the United States – Philadelphia. The findings are important to learn how air quality is affected in suburban and semi-rural areas near the major city. The study also shows the useful application of inexpensive passive sampling technique for measuring air pollution.

"The Common Myna (Sturnus tristis) in urban, rural and semi-rural areas in Greater Sydney and its surrounds." Emu - Austral Ornithology, 115(3), p. 287

During the Pianura Padana Produzione di Ozono (PIPAPO) field campaign (May–June 1998), aerosol measurements were performed at an urban site and a semirural site to determine the particulate matter chemical composition in the Milan area. Aerosol samples were collected on filters for subsequent chemical analysis using virtual impactors. Possible sampling artifacts for semivolatile particulate species were addressed. Our NH4NO3 measurements were successfully compared with artifact free wet denuder‐wet aerosol collector sampler data. Positive sampling artifacts for organic species were corrected using the back‐to‐back filter technique, allowing us to assess the lower limit for particulate organic carbon (POC) concentrations. Aerosol size distributions were measured on‐line with differential mobility analyzers (DMA). The variations in the submicron aerosol mass concentration estimated from chemical analyses compared well with the variations in the submicron particle volume calculated from number size distributions. At both sites, 70% of the PM10 mass was found in the submicron fraction. The mean submicron aerosol mass concentrations were 28 μg m−3 and 20 μg m−3 at the urban site and the semirural site, respectively. The correlations between NH4+ and NO3− + 2SO4= indicate that strong acids were fully neutralized at both sites. At the urban site the submicron concentrations of NH4NO3, (NH4)2SO4, and POC were 8.1 μg m−3, 6.3 μg m−3, and 6.4 μgC m−3, respectively. At the semi‐rural site, these concentrations were 4.9 μg m−3, 4.0 μg m−3, and 5.6 μgC m−3, respectively. These results show that sulfate and nitrate contribute about the same amount to submicron aerosol mass concentration, and that particulate organic matter (POM) could be the major component of the aerosol submicron mass in the Milan region, especially in semirural areas. The correlation between normalized concentrations of POM and O3 observed at the semirural site suggests that POM results at least partly from photochemical oxidation of volatile organic compounds (VOC). It is likely that reducing anthropogenic VOC emissions would lead to lower POC and total submicron aerosol concentrations in semirural areas around Milan.

Comparison of aerosol acidity in urban and semi-rural environments

In Australia, the introduced Common Myna (Acridotheres tristis) is commonly believed to aggressively displace native birds and outcompete them for food and nest resources. However, the current paucity of scientific evidence makes it difficult to devise appropriate management strategies for protection of urban bird populations. This study investigates the way in which the Common Myna uses the urban environment and interacts with other species while foraging and nesting in Sydney, Australia. The bird community varied between habitat types along an urbanisation gradient, and the abundance of the Common Myna increased significantly with the degree of habitat modification. Surveys of the frequency of interspecific interactions revealed that the Common Myna did not initiate a significantly greater number of aggressive encounters than did other species. Focal observations of two potential native competitors showed that despite foraging in close proximity, the Common Myna rarely interfered with feeding activity. Assessment of natural tree hollow occupancy found that Common Mynas used significantly fewer tree hollows than did native species. Analysis of nest site selection indicated that Common Mynas chose to nest in more highly modified habitats, and in artificial structures rather than in vegetation. These findings suggest that, in this study area, Common Mynas have little competitive impact on resource use by native bird species in the urban matrix. The logical conclusion of these results is that the substantial efforts currently directed towards culling of Common Mynas in heavily urbanised environments is misdirected, and resources would be better directed to improvement of natural habitat quality in these areas if the purpose of control is to enhance urban bird diversity.

Emerging crises for resources and energy has became one of the major global issues. Unstoppable population and urban growth is demanding shelter. The figure for estimated housing shortage across the world according to the internationally recommended standards is 428,700,000 units. By the year 2030, an additional 3 billion people, about 40 percent of the world’s population, will need access to housing. This translates into a demand for 96,150 new affordable units every day and 4000 every hour.(United Nation –Habitate:2005)(128). All this unstoppable global population growth is resulting in high demand supply gap between resources and thus present trend concentrate to satisfy and minimize this gap. This shooting urbanization problem is leading towards diversion for easy and fast construction methodology.Along with this the problems associated to it are also increasing globally. The problem of Urban Heat Island and Urban Canyon Effect, CO2 emission , Green House Effect , Resource depletion and all such problems are demanding global attention to overcome it and make habitant sustainable for safeguarding future generations to come. The major hurdle for application of sustainable construction is barrier of human mind who concentrates more on initial cost of construction and negligence towards operations energy cost and pay back period calculations.The aim of the paper is to show feasibility of application of waste in construction elements like wall by analysing thermo resistive property of such waste filled cavity wall and equivalence cooling effect calculations for conventional clay brick wall , AC sheets , cavity wall and various waste filled cavity wall by making model and process of simulation using Ansys Fluent .The results of research work shows feasibility of adopting cavity wall and waste fill cavity wall for construction of wall because of its high thermoresistive property so as to mitigate global problems like Urban Heat Islands and operational energy consumption.

Studies in alert preparations have demonstrated that ocular motoneurons exhibit a phasic–tonic firing rate related to eye velocity and position, respectively. The slopes of these relationships are higher in motoneurons with higher recruitment threshold and have been proposed to depend upon synaptic input. To investigate this hypothesis, motoneurons of the rat oculomotor nucleus were recorded in a brain slice preparation in control conditions and during glutamate (5 μm) application to the bath. Glutamate did not affect membrane potential or input resistance, but produced a decrease in rheobase and depolarization voltage as a function of the current needed for generating a maintained repetitive discharge (recruitment threshold current). In addition, glutamate compressed the range of recruitment threshold current (0.1–0.4 nA) as compared to the control (0.15–0.7 nA). Glutamate exposed motoneurons showed an increase in the tonic frequency gain and the peak frequency. Such increments depended on the recruitment threshold current and the last recruited motoneurons almost doubled the tonic frequency gain (35.2 vs. 57.9 spikes s(−1) nA(−1)) and the peak frequency (52.4 vs. 102.6 spikes s(−1)). Finally, glutamate increased the spike frequency adaptation due to a significant increase in the phasic firing component as compared to the tonic one. In conclusion, glutamate modulates tonic and phasic discharge properties as a function of the recruitment threshold current and, presumably, motoneuron size. These findings contribute to understand the link between cellular functions and motoneuron discharge during oculomotor behaviour.

Chilli peppers from Pakistan are consumed locally and also exported. Their quality is compromised by aflatoxins (AF) contamination. AF in chillies from rural, semi-rural and urban areas of the Punjab region of Pakistan were determined. Twenty-three (52.3%), 22 (50%) and 29 (65.9%) samples from rural, semi-rural and urban areas respectively, contained levels of aflatoxins which exceeded the European Union limits of >5 µg kg−1 for AFB1 and >10 µg kg−1 for total AF that apply to spices. Mean values for AFB1 in ground samples were 23.8, 14.8 and 14.0 µg kg−1 for rural, semi-rural and urban areas, respectively. Mean total AF in ground samples were 27.7, 17.7 and 16.2 µg kg−1 from equivalent locations. Eleven (50%), 12 (54.5%) and 14 (63.6%) whole samples from rural, semi-rural and urban areas, respectively, contained total levels of AF that exceeded European Union limits. The data indicate that individual localities have particular problems. In conclusion, the concentrations were often greater than the statutory limits set by the European Union.

Birdsong is commonly associated with sexual selection. It can influence mate choice through honestly signaling the emitter's quality. Such quality may be reflected, among other factors, in body condition and bite force. The Green-winged Saltator (Saltator similis) is a good model species to assess such relationships because males defend their territories throughout the year and sing a stereotyped song, which is known to be associated with sexual selection. The objective of this work is to assess the relationships among song structure, vocal individuality, and possible fitness indicators (body condition, morphology, and bite force) in captive male Green-winged Saltators. We conducted a linear discriminant analysis (LDA) to assess vocal individuality and to highlight the principal acoustic variables associated with it. We conducted Y-Aware PCAs to evaluate the relationship between the body condition index, bite force, and morphometric and bioacoustic variables. The morphometric variables, particularly head width and length, explained 23% of the bite force variation. The acoustic variation explained 36.17% of body condition index variation, but a small nonsignificant amount of bite force (12%). From the acoustic variables, peak frequency and high frequency of the last syllable, slope of the first syllable, and emission rate showed significant negative relationships with body condition. The LDA model based on acoustic variables had a 97.47% accuracy, although this result might also reflect regional song dialects. The acoustic variables most relevant to individual classification (first syllable duration, last syllable duration, whole-song slope, and whole-song duration) are not the same variables that had a stronger relationship to body condition. Besides that, there can be a weaker mixed signaling, as variables related to frequency modulations were important in both contexts. Our results suggest that the song may act as an honest signal of an individual's body condition in this species.

Range expansion and habitat preferences of an introduced bird in the northwestern Arabian Peninsula: The case of the common myna Acridotheres tristis

This study describes spatiotemporal patterns from October 2015 to September 2016 for PM2.5 mass and carbon measurements in rural (Kosmarra), urban (Raipur), and industrial (Bhilai) environments, in Chhattisgarh, Central India. Twenty-four-hour samples were acquired once every other week at the rural and industrial sites. Twelve-hour daytime and nighttime samples were acquired either a once a week or once every other week at the urban site. Each site was equipped with two portable, battery-powered, miniVol air samplers with PM2.5 inlets. Annual average PM2.5 mass concentrations were 71.8 ± 27µgm-3 at the rural site, 133 ± 51µgm-3 at the urban site, and 244.5 ± 63.3µgm-3 at the industrial site, ~ 2-6 times higher than the Indian Annual National Ambient Air Quality Standard of 40µgm-3. Average monthly nighttime PM2.5 and carbon concentrations at the urban site were consistently higher than those of daytime from November 2015 to April 2016, when temperatures were low. Annual average total carbon (TC = OC + EC) at the urban (46.8 ± 23.8µgm-3) and industrial (98.0 ± 17.2µgm-3) sites also exceeded the Indian PM2.5 NAAQS. TC accounted for 30-40% of PM2.5 mass. Annual average OC ranged from 17.8 ± 6.1µgm-3 at the rural site to 64 ± 9.4µgm-3 at the industrial site, with EC ranging from 4.51 ± 2.2 to 34.01 ± 7.8µgm-3. The average OC/EC ratio at the industrial site (1.88) was 18% lower than that at the urban site and 52% lower than that at the rural site. OC was attributed to 43.0% of secondary organic carbon (SOC) at the rural site, twice that estimated for the urban and industrial sites. Mortality burden estimates for PM2.5 EC are 4416 and 6196 excess deaths at the urban and industrial sites, respectively, during 2015-2016.

Urbanization and maternal hormone transfer: Endocrine and morphological phenotypes across ontogenetic stages

PP-30-013 Background/Aims: Spatial patterns of nitrogen oxides (NOx) and particulate matter (PM), 2 major traffic-related air pollutants in urban environments, have not been characterized in most cities. The purpose of this study is to characterize horizontal and vertical distributions of NOx, PM concentration distribution, and investigate factors affecting their distributions in Taipei. Methods: We used a population density based sampling strategy to select 40 locations as our sampling sites in Taipei, including 20 urban background sites at small alleys with limited traffics and 20 traffic background sites neighboring roads with 4–6 lanes. Among these monitoring sites, 11 sites were used to characterize vertical profiles of NOx in Taipei. We used Ogawa passive samplers to measure NOx and NO2, and Harvard impactors to measure PM10, PM2.5 simultaneously for 2 weeks per season for 2 seasons during 2009–2010. Results: NOx concentrations at traffic sites (46.6 ppb) were significantly higher than the urban background sites (31.1 ppb). And PM2.5 concentration at traffic sites is 2.72 μg/m3 higher than at urban sites. PM10 concentration at traffic sites is 9.05 μg/m3 higher than at urban sites. Seasonal difference was significant for both NOx and PM concentrations. On the aspect of the vertical profile of NOx, the NOx and NO2 concentrations at 4th–6th floors were 0.79 times and 0.75 times lower than the concentrations at first—third floors, the NOx and NO2 concentrations at seventh—eighth floors were 0.64 times and 0.67 times lower than the concentrations which at first—third floors, respectively. There is a significant difference between our sampling results and the monitoring data from fixed-site stations nearby. Conclusion: Our study indicates that traffic pattern is an important factor for influencing the spatial distributions of both NOx and PM in urban environments.

The Northern Mockingbird (Mimus polyglottos) is a successful urban adaptor known to display flexibility in foraging, nesting, and anti-predator behavior. Its vocal behavior is also complex, with a breeding song composed of a wide variety of non-mimetic and mimetic elements, or “syllable types.” We tested the hypothesis that Northern Mockingbird adaptation to urban settings includes changes in its vocal behavior in noisy urban environments. We studied an urban/suburban mockingbird population to test the effect of urban background noise on breeding song frequency and syllable-type composition. Given that urban noise overlaps most strongly with low-frequency vocalizations, a phenomenon known as “signal masking,” we predicted a positive association between noise levels and mockingbird average peak frequency (a measure of vocalization power). We further predicted a positive effect of noise levels on the peak frequency of the lowest-pitched syllable type in a mockingbird’s song, no effect on the peak frequency of the highest-pitched syllable type, and thus a negative effect on mockingbird peak frequency range. Lastly, we predicted a negative effect of background noise on the use of syllable types experiencing heavy signal masking and, conversely, a positive effect on the use of syllable types experiencing minimal signal masking. We found a significant positive effect of noise levels on both average peak frequency and peak frequency of the lowest-pitched syllable type, but no effect on the peak frequency of the highest-pitched syllable type and peak frequency range. In addition, as background noise levels increased, we found significant declines in the percentages of heavily masked syllable types (1–3 kHz) and significant increases in the percentages of syllable types in the 3–5 kHz range; percentages of syllable types &gt;5 kHz were, however, unaffected by background noise. These results were consistent with the hypothesis that Northern Mockingbird breeding songs change in pitch and syllable-type composition in noisy settings, providing further evidence that songs of urban-adapting species differ in noisy environments.