scholarly journals Urbanization, Electromagnetic Radiation and Sparrows: A Case Study from Guwahati, India

2021 ◽  
Author(s):  
Anukul Nath ◽  
Hilloljyoti Singha ◽  
Bibhuti Prasad Lahkar
Keyword(s):  
Habitat Use ◽  
Electromagnetic Radiation ◽  
House Sparrow ◽  
Radiation Risk ◽  
Bird Species ◽  
Tree Sparrow ◽  
Point Counts ◽  
Wireless Telecommunication ◽  
Guwahati City ◽  
Living Species

Abstract The persisting growth of wireless telecommunication technology causes increased electrosmog. Exposure to wide-ranging radiofrequency electromagnetic fields is thought to be a concern for all the living species across the globe. Studies have shown possible effects of electromagnetic radiation on various organisms including electromagnetic radiation risk on birds, but the outcomes were inconsistent. Here, we investigated if there is any impact of electromagnetic radiation on the abundance and habitat use of sympatric House Sparrow and Tree Sparrow in Guwahati City, India. In addition, we did a comparative analysis of previous work that had been conducted on possible effects of EMR on wild birds in field condition. We collected sparrow abundance in selected urbanization gradients temporally over a period of two years in 45 locations and spatially covering 168 locations in the eastern part of Guwahati City. Point counts were carried out, and successively we measured the electromagnetic radiation along with other ecological covariates. It was observed that ecological variables contributed significant variation to explain the habitat use of sparrows in Guwahati City compared to electromagnetic radiation. We observed that House Sparrow had quadratic relationship and Tree sparrow had negative association with increasing urbanization. Studies carried out in the past on the impacts of electromagnetic radiation on birds outside the lab condition had not considered other ecological covariates, which could also influence the life history needs of the bird species. Our study emphasized that the ecological covariates should be taken into consideration while studying the effect of electromagnetic radiation on wild organisms.

scholarly journals Electromagnetic Pollution as a Possible Explanation for the Decline of House Sparrows in Interaction with Other Factors

Birds ◽  
2021 ◽  
Vol 2 (3) ◽  
pp. 329-337
Author(s):  
Alfonso Balmori
Keyword(s):  
Electromagnetic Radiation ◽  
Thermal Effects ◽  
House Sparrow ◽  
Bird Species ◽  
Passer Domesticus ◽  
The Other ◽  
Rapid Decline ◽  
House Sparrows ◽  
Electromagnetic Pollution ◽  
The Impact

In recent decades, there has been a decline of the House Sparrow (Passer domesticus), mainly in European cities, and several hypotheses have been proposed that attempt to determine the causes of this rapid decline. Previous studies indicated that house sparrows were significantly negatively associated with increasing electromagnetic radiation and sparrows disappeared from areas most polluted. In addition, there are many studies on the impact of radiation on other bird and non-bird species, as well as numerous laboratory studies that demonstrated detrimental effects at electric field strength levels that can be found in cities today. Electromagnetic radiation is the most plausible factor for multiple reasons, including that this is the only one that affects the other hypotheses proposed so far. It is a type of pollution that affects productivity, fertility, decreases insects (chicken feed), causes loss of habitat, decreases immunity and can promote disease. Additionally, the recent sparrow decline matches the deployment of mobile telephony networks. Further, there are known mechanisms of action for non-thermal effects of electromagnetic radiation that may affect sparrows causing their decline. Thus, electromagnetic radiation must be seriously considered as a factor for house sparrows’ decline, probably in synergy with the other factors previously proposed.

Migration patterns and seasonal forest use by birds in the Brazilian Pantanal

2017 ◽  
Vol 27 (3) ◽  
pp. 371-387 ◽  
Author(s):  
JOÃO BATISTA DE PINHO ◽  
MÔNICA ARAGONA ◽  
KARLO YOSHIHIRO PIOTO HAKAMADA ◽  
MIGUEL ÂNGELO MARINI
Keyword(s):  
Habitat Use ◽  
Bird Species ◽  
Occupancy Models ◽  
Neotropical Forests ◽  
Migration Patterns ◽  
Point Counts ◽  
Run Off ◽  
Forest Use ◽  
Migratory Patterns ◽  
Landscape Units

SummaryThe use of forest habitats and migratory patterns are still unclear for tropical birds. Some are described herein for the Pantanal wetlands of Brazil. Thus, our aim was to describe different patterns of forest habitat use by birds and classify the birds’ migration patterns for the northern Pantanal region, Brazil. From September 1999 to December 2003, we sampled four forest types, during which we collected standardised data with mist-net captures and point counts, with additional ad lib. observations. We recorded 214 bird species: 113 (52.8%) were total habitat generalists; 41 (19.2%) were forest generalists; 19 (8.9%) were flooded habitat specialists; and 28 (13.1%) were not classified due to the low number of records; three other categories of habitat use divide the remaining 6% of records. About half of the species showed some migratory behaviour, these were classified by us according to the season they spent in the area: 121 species (56.5%) as residents, 28 (13.1%) as run-off and dry migrants, 11 (5.1%) as run-off (winter) migrants, eight (3.7%) as dry (breeding) migrants, eight (3.7%) as dry and flooding (summer) migrants, eight (3.7%) as flooding migrants, three (1.4%) as flooding and run-off migrants, and 27 (12.6%) as uncommon. We constructed community occupancy models with six of the eight patterns of migration described; flooding migrants and run-off migrants were not modelled since the few species recorded also had very few detections. As expected, the model confirmed that species from all six tested migration patterns arrive and depart from the Pantanal across the seasons. Contrary to most Neotropical forests, there was a high percentage (43.5%) of non-resident species. The results show the need of investing heavily in preserving different landscape units within the Pantanal, but also in the surrounding Cerrado region, in order to conserve resident and short distance intra-tropical migrants.

scholarly journals Habitat use during post-pre-breeding period in a Rock Sparrow Petronia petronia population

2020 ◽  
Vol 89 (2) ◽  
Author(s):  
Bruno Santucci ◽  
Andrea Pulvirenti ◽  
Samuele Ramellini ◽  
Marinella Miglio
Keyword(s):  
Standard Deviation ◽  
Habitat Use ◽  
Social Behaviour ◽  
Bird Species ◽  
Breeding Period ◽  
Habitat Types ◽  
Tree Sparrow ◽  
Stage Of Development ◽  
Wintering Habitat ◽  
Cereal Fields

Most studies focusing on Rock Sparrow populations concern their breeding biology. With this study, we aim to investigate the wintering habitat and social behaviour outside the breeding period. In the study area the species is present all year long, and, outside the breeding period, birds frequently gather together on flocks of different size (3-150 individuals), which are larger in the coldest months. The habitat types most used by the species were cereal fields with crops in their first stage of development (17.71% ± 4.72 Standard Deviation) and arable stubbles, both of them with bushes and trees on their boundaries (82.4%), which likely provide shelters from predators. The bird species most frequently associated with Rock Sparrow flocks were Tree Sparrow, Starling and Crested Lark. Holes in the roof tiles of the same abandoned buildings used for breeding were also used as night shelters. The average hours of leaving and returning to the shelters was strictly related to the photoperiod (rs = -0.9405; 0.8810).

scholarly journals THE IMPORTANCE OF THE LONG-EARED OWL ASIO OTUS OTUS (L.) IN RODENT CONTROL

1970 ◽  
Vol 63 ◽  
Author(s):  
Victoria Nistreanu
Keyword(s):  
Dominant Species ◽  
House Sparrow ◽  
Common Vole ◽  
Bird Species ◽  
Botanical Garden ◽  
Rodent Species ◽  
Microtus Arvalis ◽  
Rodent Control ◽  
Tree Sparrow ◽  
The Common

The trophic spectrum of the long-eared owl was studied in two localities of Someshul Mic basin: Cluj-Napoca city and Cojocna village. 2131 pellets were collected: 1403 pellets from Cluj-Napoca Botanical Garden and 728 from Cojocna. 6161 micromammal and bird skulls and bones were separated: 4238 from the pellets collected in Cluj-Napoca and 1923 from those collected in Cojocna. The rodents percent was 84,52% in Cluj-Napoca and 99,12% Cojocna pellets. 4 insectivore species, 12 rodent species and 10 bird species were found in pellets. The most abundant and the dominant species is the common vole (Microtus arvalis) with 64,08% in Cluj-Napoca and with 79,43% in Cojocna. Among birds the most abundant are the house sparrow and the tree sparrow, which constitute almost 70% from all the birds.

Three hundred years of House Sparrow (Passer domesticus) persecution in Germany

2007 ◽  
Vol 34 (2) ◽  
pp. 307-317 ◽  
Author(s):  
J. SEITZ
Keyword(s):  
Rural Areas ◽  
House Sparrow ◽  
Bird Species ◽  
Passer Domesticus ◽  
Second World War ◽  
Population Increase ◽  
World War ◽  
Large Numbers ◽  
Urban And Rural Areas ◽  
Second World

Modernization of agriculture, economic development and population increase after the end of the Thirty Years' War caused authorities in many parts of Germany to decree the eradication of so-called pest animals, including the House Sparrow. Farmers were given targets, and had to deliver the heads of sparrows in proportion to the size of their farms or pay fines. At the end of the eighteenth century German ornithologists argued against the eradication of the sparrows. During the mid-nineteenth century, C. L. Gloger, the pioneer of bird protection in Germany, emphasized the value of the House Sparrow in controlling insect plagues. Many decrees were abolished because either they had not been obeyed, or had resulted in people protecting sparrows so that they always had enough for their “deliveries”. Surprisingly, various ornithologists, including Ernst Hartert and the most famous German bird conservationist Freiherr Berlepsch, joined in the war against sparrows at the beginning of the twentieth century, because sparrows were regarded as competitors of more useful bird species. After the Second World War, sparrows were poisoned in large numbers. Persecution of sparrows ended in Germany in the 1970s. The long period of persecution had a significant but not long-lasting impact on House Sparrow populations, and therefore cannot be regarded as a factor in the recent decline of this species in urban and rural areas of western and central Europe.

Die Brutvogelfauna eines Nadelwaldes der nördlichen Voralpen nach dem Sturm Lothar

2017 ◽  
Vol 168 (2) ◽  
pp. 59-66
Author(s):  
Pierre Mollet ◽  
René Hardegger ◽  
Res Altwegg ◽  
Pius Korner ◽  
Simon Birrer
Keyword(s):  
Forest Succession ◽  
Coniferous Forest ◽  
Bird Species ◽  
Individual Species ◽  
Mountain Forest ◽  
Breeding Bird ◽  
Point Counts ◽  
Federal Institute ◽  
Central Switzerland ◽  
Bird Fauna

Breeding bird fauna in a coniferous forest in the northern Prealps after storm Lothar In a 70-hectare large coniferous forest located on the northern edge of the Alps in central Switzerland, Canton of Obwalden, at an altitude of 1260 to 1550 metres above sea level, we surveyed the local breeding bird fauna in 2002 and 2013 by means of point counts as well as additional area searches for rare species. In December 1999, hurricane Lothar caused two large windthrow areas and several smaller areas with scattered throws in the survey range. We found a total of 48 breeding bird species, which is a very diverse species composition for a mountain forest. In the eleven years between surveys, a decline in distribution or abundance was recorded for four species, while seven species showed an increase; a further four species showed no change. For the remaining species, the data sets were too small to reliably estimate changes. A comparison with forest structure data provided by the Swiss Federal Institute of Forest, Snow and Landscape Research WSL revealed that for five bird species, the changes in distribution or abundance could be explained at least partially by forest succession. In order to obtain realistic distribution and abundance values in this kind of breeding bird survey, it is essential to collect large enough samples and to consider the detection probability of each individual species using appropriate statistical methods.

scholarly journals Current Land Bird Distribution and Trends in Population Abundance Between 1982 and 2012 on Rota, Mariana Islands

2015 ◽  
Vol 6 (2) ◽  
pp. 511-540 ◽  
Author(s):  
Richard J. Camp ◽  
Kevin W. Brinck ◽  
P. Marcos Gorresen ◽  
Fred A. Amidon ◽  
Paul M. Radley ◽  
...  
Keyword(s):  
Land Cover ◽  
Bird Species ◽  
Ratio Estimator ◽  
Occupancy Models ◽  
Tree Sparrow ◽  
Range Restriction ◽  
Widespread Distribution ◽  
Significant Difference ◽  
Eurasian Tree Sparrow ◽  
Bird Distribution

Abstract The western Pacific island of Rota is the fourth largest human-inhabited island in the Mariana archipelago and designated an Endemic Bird Area. Between 1982 and 2012, 12 point-transect distance-sampling surveys were conducted to assess bird population status. Surveys did not consistently sample the entire island; thus, we used a ratio estimator to estimate bird abundances in strata not sampled during every survey. Trends in population size were reliably estimated for 11 of 13 bird species, and 7 species declined over the 30-y time series, including the island collared-dove Streptopelia bitorquata, white-throated ground-dove Gallicolumba xanthonura, Mariana fruit-dove Ptilinopus roseicapilla, collared kingfisher Todiramphus chloris orii, Micronesian myzomela Myzomela rubratra, black drongo Dicrurus macrocercus, and Mariana crow Corvus kubaryi. The endangered Mariana crow (x̄  =  81 birds, 95% CI 30–202) declined sharply to fewer than 200 individuals in 2012, down from 1,491 birds in 1982 (95% CI  =  815–3,115). Trends increased for white tern Gygis alba, rufous fantail Rhipidura rufifrons mariae, and Micronesian starling Aplonis opaca. Numbers of the endangered Rota white-eye Zosterops rotensis declined from 1982 to the late 1990s but returned to 1980s levels by 2012, resulting in an overall stable trend. Trends for the yellow bittern Ixobrychus sinensis were inconclusive. Eurasian tree sparrow Passer montanus trends were not assessed; however, their numbers in 1982 and 2012 were similar. Occupancy models of the 2012 survey data revealed general patterns of land cover use and detectability among 12 species that could be reliably modeled. Occupancy was not assessed for the Eurasian tree sparrow because of insufficient detections. Based on the 2012 survey, bird distribution and abundance across Rota revealed three general patterns: 1) range restriction, including Mariana crow, Rota white-eye, and Eurasian tree sparrow; 2) widespread distribution, low abundance, including collared kingfisher, island collared-dove, white-throated ground-dove, Mariana fruit-dove, white tern, yellow bittern, black drongo, and Micronesian myzomela; and 3) widespread distribution, high abundance, including rufous fantail and Micronesian starling. The Mariana crow was dispersed around the periphery of the island in steep forested land-cover types. In contrast, the Rota white-eye was restricted to the high-elevation mesa. Only for the white-throated ground-dove was there a significant difference among cover types, with lower occupancy in open field than in forested areas. Vegetation was included in the best-fit occupancy models for yellow bittern, black drongo, Micronesian myzomela, and Micronesian starling, but vegetation type was not a significant variable nor included in the top models for the remaining five species: white tern, island collared-dove, Mariana fruit-dove, collared kingfisher, and rufous fantail. Given declining population trends, the Rota bird-monitoring program could benefit from establishing threshold and alert limits and identifying alternative research and management actions. Continued monitoring and demographic sampling, in conjunction with ecological studies, are needed to understand why most bird species on Rota are declining, identify the causative agents, and assess effectiveness of conservation actions, especially for the Mariana crow.

Overlap in avian communities produces unimodal richness peaks on Bornean mountains

2018 ◽  
Vol 34 (2) ◽  
pp. 75-92 ◽  
Author(s):  
Ryan C. Burner ◽  
Alison R. Styring ◽  
Chandradewana Boer ◽  
Frederick H. Sheldon
Keyword(s):  
Species Richness ◽  
Bird Species ◽  
Sufficient Evidence ◽  
Altitudinal Distribution ◽  
Bird Species Richness ◽  
Point Counts ◽  
Habitat Gradient ◽  
Quantitative Analyses ◽  
Meta Analyses ◽  
Replicated Systems

Abstract:Altitudinal gradients provide tractable, replicated systems in which to study changes in species richness and community composition over relatively short distances. Previously, richness was often assumed to follow a monotonic decline with altitude, but recent meta-analyses show that more complex patterns, including mid-altitude richness peaks, are also prevalent in birds. In this study, we used point counts to survey birds at multiple altitudes on three mountains on the island of Borneo in Sundaland, an area for which quantitative analyses of avian altitudinal distribution are unavailable. In total we conducted 1088 point counts and collected associated habitat data at 527 locations to estimate species richness by altitude on Mt Mulu (2376 m), Mt Pueh (1550 m) and Mt Topap Oso (1450 m). On Mulu, the only mountain with an intact habitat gradient, bird species richness peaks at 600 m. Richness appeared to peak at 600 m on Totap Oso as well, but on Pueh it peaked several hundred metres higher. The richness peak on Mulu differs from that predicted by null models and is instead caused by the overlap of distinct lowland and montane avifaunas, supporting the faunal overlap hypothesis. This finding provides further evidence that a lack of coincidence between peak turnover and peak richness is not sufficient evidence to rule out faunal overlap as a causal factor.

Problems with Avian Point Counts for Estimating Density of Northern Bobwhite—A Case Study

2011 ◽  
Vol 2 (1) ◽  
pp. 117-121 ◽  
Author(s):  
Roger D. Applegate ◽  
Robert E. Kissell ◽  
E. Daniel Moss ◽  
Edward L. Warr ◽  
Michael L. Kennedy
Keyword(s):  
Count Data ◽  
Distance Sampling ◽  
Bird Species ◽  
Northern Bobwhite ◽  
Model Fit ◽  
Point Count ◽  
Point Counts ◽  
Occupancy Estimation ◽  
Detection Probabilities

Abstract Point count data are used increasingly to provide density estimates of bird species. A favored approach to analyze point count data uses distance sampling theory where model selection and model fit are important considerations. We used uniform and half normal models and assessed model fit using χ2 analysis. We were unsuccessful in fitting models to 635 northern bobwhite Colinus virginianus observations from 85 avian point locations spanning 6 y (P ≤ 0.05). Most observations (74%) occurred in the outermost (>100-m) distance radius. Our results violated the assumptions that all observations at the point are detected. The assumption that birds were assigned to the correct distance interval also was probably violated. We caution managers in implementing avian point counts with distance sampling when estimating northern bobwhite population density. We recommend exploring other approaches such as occupancy-estimation and modeling for estimating detection probabilities.

scholarly journals Comparison of predation by two suburban cats in New Zealand

2017 ◽  
Vol 3 (1) ◽  
pp. 85-90 ◽  
Author(s):  
John E. C. Flux
Keyword(s):  
New Zealand ◽  
House Sparrow ◽  
Bird Species ◽  
House Mice ◽  
Domestic Cats ◽  
Mesopredator Release ◽  
Song Thrush ◽  
Top Predators ◽  
European Rabbits ◽  
Native Birds

AbstractTo study the effects domestic cats may have on surrounding wildlife, a complete list was made of 558 items caught in the garden or brought into the house by one cat over 17 years, from 1988 to 2005. The effect on prey populations was assessed by comparing their abundance with the previous 15 years’ population without a cat. On balance, this cat (Cat 1) was clearly beneficial to the native bird species by killing rodents and deterring mustelids. The diet of a second cat (Cat 2) was recorded in the same way from 2006 to 2016. This cat caught half the number of items 148:287, but in the same proportions: house mice (37.8:42.6); ship rats (12.8:12.1); European rabbits (all young) (8.1:6.7); weasels (0.7:0.4); dunnock (12.8:9.2); house sparrow (2.0:3.1); blackbird (2.7:2.5); song thrush (1.4:1.3); European greenfinch (0.7:5.8); chaffinch (0.7:3.3); silvereye (10.1:8.3); New Zealand fantail (2.0:1.0); lizards (8.1:1.7). Despite this, there were significant differences: Cat 2 avoided finches (2:28, P = 0.004), and took a few more lizards (12:5). For both cats, birds apparently formed about a third of their diet: 33.4% and 34.5%, but comparison of the proportion of birds and rodents brought into the house (12:92) and found dead away from the house (49:45) implies that 320 rodent kills may have been missed, being far more difficult to find. As top predators, these cats were clearly beneficial to native birds, and proposed control or elimination may precipitate mesopredator release and a rabbit problem.

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