scholarly journals Species-Specific Responses of Bird Song Output in the Presence of Drones

Drones ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 1
Author(s):  
Andrew M. Wilson ◽  
Kenneth S. Boyle ◽  
Jennifer L. Gilmore ◽  
Cody J. Kiefer ◽  
Matthew F. Walker

Drones are now widely used to study wildlife, but their application in the study of bioacoustics is limited. Drones can be used to collect data on bird vocalizations, but an ongoing concern is that noise from drones could change bird vocalization behavior. To test for behavioral impact, we conducted an experiment using 30 sound localization arrays to track the song output of 7 songbird species before, during, and after a 3 min flight of a small quadcopter drone hovering 48 m above ground level. We analyzed 8303 song bouts, of which 2285, from 184 individual birds were within 50 m of the array centers. We used linear mixed effect models to assess whether patterns in bird song output could be attributed to the drone’s presence. We found no evidence of any effect of the drone on five species: American Robin Turdus migratorius, Common Yellowthroat Geothlypis trichas, Field Sparrow Spizella pusilla, Song Sparrow Melospiza melodia, and Indigo Bunting Passerina cyanea. However, we found a substantial decrease in Yellow Warbler Setophaga petechia song detections during the 3 min drone hover; there was an 81% drop in detections in the third minute (Wald test, p < 0.001) compared with before the drone’s introduction. By contrast, the number of singing Northern Cardinal Cardinalis cardinalis increased when the drone was overhead and remained almost five-fold higher for 4 min after the drone departed (p < 0.001). Further, we found an increase in cardinal contact/alarm calls when the drone was overhead, with the elevated calling rate lasting for 2 min after the drone departed (p < 0.001). Our study suggests that the responses of songbirds to drones may be species-specific, an important consideration when proposing the use of drones in avian studies. We note that recent advances in drone technology have resulted in much quieter drones, which makes us hopeful that the impact that we detected could be greatly reduced.

2020 ◽  
Author(s):  
Andrew M. Wilson ◽  
Kenneth S. Boyle ◽  
Jennifer L. Gilmore ◽  
Cody J. Kiefer ◽  
Matthew F. Walker

AbstractDrones are now widely used to study wildlife, but applications for studying bioacoustics have been limited. Drones can be used to collect data on bird vocalizations, but an ongoing concern is that noise from the drones could change bird vocalization behavior. To test this behavioral impact we conducted an experiment using 30 sound localization arrays to track the song output of seven songbird species before, during, and after a 3-minute flight of a small quadcopter drone hovering at 50 m above ground level. We analyzed 8,303 song bouts, of which 2,285 song bouts of 184 individual birds were within 50 meters of the array centers. We used linear mixed effect models to assess patterns in song output showed patterns that could be attributed to the drone’s presence. We found no evidence of any effect of the drone for five species: American Robin Turdus migratorius, Common Yellowthroat Geothlypis trichas, Field Sparrow Spizella pusilla, Song Sparrow Melospiza melodia, and Indigo Bunting Passerina cyanea. However, we found a substantial decrease in Yellow Warbler Setophaga petechia song detections during the 3-minute drone hover, such that there was an 81% drop in detections in the 3rd minute (Wald-test, p<0.001), compared with before the drone’s introduction. In contrast, the number of singing Northern Cardinal Cardinalis cardinalis increased after the drone was introduced, and remained almost five-fold higher for 4-minutes after the drone departed (P<0.001). Further, we found an increase in cardinal contact/alarm calls when the drone was overhead, with the elevated calling-rate sustaining for 2 minutes after the drone had departed (P<0.001). Our study suggests that responses of songbirds to drones may be species-specific, an important consideration when proposing the use of drones in avian studies. We note that recent advances in drone technology have resulted in much quieter drones, which makes us hopeful that the impacts that we detected could be greatly reduced.


2020 ◽  
Vol 14 (3) ◽  
pp. 253-284
Author(s):  
Ranjan Kumar Mohanty ◽  
Sidheswar Panda

The study investigates the macroeconomic effects of public debt in India during 1980–2017 using a structural vector autoregression framework. The objective is to examine the impact of public debt on the interest rate, investment, inflation and economic growth in India. The results of the impulse response functions show that public debt has an adverse impact on economic growth but a positive impact on the long-term interest rate in the short run and a mixed effect (both negative and positive) on investment and inflation. We also find that domestic debt has a more adverse impact on the economy than external debt. The estimated variance decomposition analysis finds that much of the variation in selected macro variables are explained by public debt and growth in India. This study suggests that public debt especially domestic debt should be controlled and channelled productively to have a favourable impact on the economy. JEL Classification: H63, O40, C40


Author(s):  
Oskar Wiśniewski ◽  
Wiesław Kozak ◽  
Maciej Wiśniewski

AbstractCOVID-19, which is a consequence of infection with the novel viral agent SARS-CoV-2, first identified in China (Hubei Province), has been declared a pandemic by the WHO. As of September 10, 2020, over 70,000 cases and over 2000 deaths have been recorded in Poland. Of the many factors contributing to the level of transmission of the virus, the weather appears to be significant. In this work, we analyze the impact of weather factors such as temperature, relative humidity, wind speed, and ground-level ozone concentration on the number of COVID-19 cases in Warsaw, Poland. The obtained results show an inverse correlation between ground-level ozone concentration and the daily number of COVID-19 cases.


Author(s):  
Jeff Nawrocki ◽  
Katherine Olin ◽  
Martin C Holdrege ◽  
Joel Hartsell ◽  
Lindsay Meyers ◽  
...  

Abstract Background The initial focus of the US public health response to COVID-19 was the implementation of numerous social distancing policies. While COVID-19 was the impetus for imposing these policies, it is not the only respiratory disease affected by their implementation. This study aimed to assess the impact of social distancing policies on non-SARS-CoV-2 respiratory pathogens typically circulating across multiple US states. Methods Linear mixed-effect models were implemented to explore the effects of five social distancing policies on non-SARS-CoV-2 respiratory pathogens across nine states from January 1 through May 1, 2020. The observed 2020 pathogen detection rates were compared week-by-week to historical rates to determine when the detection rates were different. Results Model results indicate that several social distancing policies were associated with a reduction in total detection rate, by nearly 15%. Policies were associated with decreases in pathogen circulation of human rhinovirus/enterovirus and human metapneumovirus, as well as influenza A, which typically decrease after winter. Parainfluenza viruses failed to circulate at historical levels during the spring. Total detection rate in April 2020 was 35% less than historical average. Many of the pathogens driving this difference fell below historical detection rate ranges within two weeks of initial policy implementation. Conclusion This analysis investigated the effect of multiple social distancing policies implemented to reduce transmission of SARS-CoV-2 on non-SARS-CoV-2 respiratory pathogens. These findings suggest that social distancing policies may be used as an impactful public health tool to reduce communicable respiratory illness.


AMB Express ◽  
2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Neeraja Punde ◽  
Jennifer Kooken ◽  
Dagmar Leary ◽  
Patricia M. Legler ◽  
Evelina Angov

Abstract Codon usage frequency influences protein structure and function. The frequency with which codons are used potentially impacts primary, secondary and tertiary protein structure. Poor expression, loss of function, insolubility, or truncation can result from species-specific differences in codon usage. “Codon harmonization” more closely aligns native codon usage frequencies with those of the expression host particularly within putative inter-domain segments where slower rates of translation may play a role in protein folding. Heterologous expression of Plasmodium falciparum genes in Escherichia coli has been a challenge due to their AT-rich codon bias and the highly repetitive DNA sequences. Here, codon harmonization was applied to the malarial antigen, CelTOS (Cell-traversal protein for ookinetes and sporozoites). CelTOS is a highly conserved P. falciparum protein involved in cellular traversal through mosquito and vertebrate host cells. It reversibly refolds after thermal denaturation making it a desirable malarial vaccine candidate. Protein expressed in E. coli from a codon harmonized sequence of P. falciparum CelTOS (CH-PfCelTOS) was compared with protein expressed from the native codon sequence (N-PfCelTOS) to assess the impact of codon usage on protein expression levels, solubility, yield, stability, structural integrity, recognition with CelTOS-specific mAbs and immunogenicity in mice. While the translated proteins were expected to be identical, the translated products produced from the codon-harmonized sequence differed in helical content and showed a smaller distribution of polypeptides in mass spectra indicating lower heterogeneity of the codon harmonized version and fewer amino acid misincorporations. Substitutions of hydrophobic-to-hydrophobic amino acid were observed more commonly than any other. CH-PfCelTOS induced significantly higher antibody levels compared with N-PfCelTOS; however, no significant differences in either IFN-γ or IL-4 cellular responses were detected between the two antigens.


Atmosphere ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 125 ◽  
Author(s):  
Brian Diffey

In the early 1970s, environmental conservationists were becoming concerned that a reduction in the thickness of the atmospheric ozone layer would lead to increased levels of ultraviolet (UV) radiation at ground level, resulting in higher population exposure to UV and subsequent harm, especially a rise in skin cancer. At the time, no measurements had been reported on the normal levels of solar UV radiation which populations received in their usual environment, so this lack of data, coupled with increasing concerns about the impact to human health, led to the development of simple devices that monitored personal UV exposure. The first and most widely used UV dosimeter was the polymer film, polysulphone, and this review describes its properties and some of the pioneering studies using the dosimeter that led to a quantitative understanding of human exposure to sunlight in a variety of behavioral, occupational, and geographical settings.


2016 ◽  
Vol 43 (2) ◽  
pp. 336-356 ◽  
Author(s):  
Franklin Amuakwa-Mensah ◽  
Louis Boakye-Yiadom ◽  
William Baah-Boateng

Purpose – The purpose of this paper is to investigate the effect of education on migration decisions focusing on rural and urban in-migrants by comparing the 2005/2006 and 2012/2013 rounds of the Ghana Living Standards Survey (GLSS5 and GLSS6). After correcting for selectivity bias, the authors observed that anticipated welfare gain and socio-economic variables such as sector of employment, sex, experience, age, educational level and marital status significantly affect an individual’s migration decision. Design/methodology/approach – The authors made use of Sjaastad’s (1962) human capital framework as a basis for examining the impact of education on migration. The migration decision equation was based on the Heckman two stage procedure. Findings – While educational attainment is observed to have a positive effect on migration decision in the period 2005/2006, the authors find a negative effect of educational attainment on migration decision in the period 2012/2013. The effect of educational attainment on migration decision in 2005/2006 for urban in-migrant is higher than the effect for rural in-migrant, with its significance varying for the different stages of educational attainment. In absolute terms, whereas the effect of secondary educational attainment on migration decisions for urban in-migrant is higher than that of rural in-migrant, the reverse holds for higher educational attainment during the period 2012/2013. Social implications – Based on the mixed effect of education on migration decision as evident from the study, policies to enhance the educational system in Ghana should be complemented with job creations in the entire country. Moreover, special attention should be given to the rural sector in such a way that the jobs to be created in the sector do not require skilled workers. With quality education and job creation, the welfare of individuals living in urban and rural areas will be enhanced. Originality/value – In spite of the importance of education in migration decisions, there is scanty literature on the rural-urban dimension. To the best of the author’s knowledge there is no literature in the Ghanaian context which examines the rural and urban perspective of the impact of education on migration with a much recent data. Further, the author consider how the determinants of migration decision have changed over time focusing on rural and urban perspectives.


1985 ◽  
Vol 117 (9) ◽  
pp. 1117-1126 ◽  
Author(s):  
Ronald M. Weseloh

AbstractThe impact of predation by Calosoma sycophanta L. on an increasing prey population was assessed by recapturing marked adult beetles, periodically observing tagged gypsy moth pupae, and examining gypsy moth pupal remains in different microhabitats. Adult beetles dispersed in random directions but many tended to remain near the trap at which they were originally caught, suggesting a low dispersal potential. About 75% of the adult beetles present in the plot on one day were still present the next day. Capture–recapture estimates suggested that there were at most about 250 male beetles and half as many females/ha in the plot. Calosoma larvae destroyed 70% of tagged gypsy moth pupae under burlap bands on tree trunks near ground level, which was much more than any other mortality factor. Although this percentage was the same when mortality was assessed by looking at pupal remains within 5 m of the ground on tree trunks, pupae higher in trees and on leaves were not attacked as frequently. On average, about 40% of the pupae present in the entire study area were destroyed by Calosoma larvae. Each female beetle in the site would have had to produce about 30 progeny to have this effect. These data suggest that a relatively low number of adult beetles can have a substantial impact on gypsy moth populations.


2016 ◽  
Vol 55 (11) ◽  
pp. 2509-2527 ◽  
Author(s):  
Jordane A. Mathieu ◽  
Filipe Aires

AbstractStatistical meteorological impact models are intended to represent the impact of weather on socioeconomic activities, using a statistical approach. The calibration of such models is difficult because relationships are complex and historical records are limited. Often, such models succeed in reproducing past data but perform poorly on unseen new data (a problem known as overfitting). This difficulty emphasizes the need for regularization techniques and reliable assessment of the model quality. This study illustrates, in a general way, how to extract pertinent information from weather data and exploit it in impact models that are designed to help decision-making. For a given socioeconomic activity, this type of impact model can be used to 1) study its sensitivity to weather anomalies (e.g., corn sensitivity to water stress), 2) perform seasonal forecasting (yield forecasting) for it, and 3) quantify the longer-term (several decades) impact of weather on it. The size of the training database can be increased by pooling data from various locations, but this requires statistical models that are able to use the localization information—for example, mixed-effect (ME) models. Linear, neural-network, and ME models are compared, using a real-world application: corn-yield forecasting over the United States. Many challenges faced in this paper may be encountered in many weather-impact analyses: these results show that much care is required when using space–time data because they are often highly spatially correlated. In addition, the forecast quality is strongly influenced by the training spatial scale. For the application that is described herein, learning at the state scale is a good trade-off: it is specific to local conditions while keeping enough data for the calibration.


2010 ◽  
Vol 48 ◽  
pp. 1-24 ◽  
Author(s):  
Jan Postberg ◽  
Hans J. Lipps ◽  
Thomas Cremer

Understanding the evolutionary origin of the nucleus and its compartmentalized architecture provides a huge but, as expected, greatly rewarding challenge in the post-genomic era. We start this chapter with a survey of current hypotheses on the evolutionary origin of the cell nucleus. Thereafter, we provide an overview of evolutionarily conserved features of chromatin organization and arrangements, as well as topographical aspects of DNA replication and transcription, followed by a brief introduction of current models of nuclear architecture. In addition to features which may possibly apply to all eukaryotes, the evolutionary plasticity of higher-order nuclear organization is reflected by cell-type- and species-specific features, by the ability of nuclear architecture to adapt to specific environmental demands, as well as by the impact of aberrant nuclear organization on senescence and human disease. We conclude this chapter with a reflection on the necessity of interdisciplinary research strategies to map epigenomes in space and time.


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