Factors influencing nesting success of the river lapwing, Vanellus duvaucelii (Lesson, 1826)

2020 ◽  
Vol 13 (3) ◽  
pp. 35-43 ◽  
Author(s):  
Himanshu Mishra ◽  
Vikas Kumar ◽  
Ashish Kumar
Keyword(s):  
Uttar Pradesh ◽  
Nesting Success ◽  
Line Transect ◽  
Nest Failure ◽  
Gangetic Plain ◽  
Factors Affecting ◽  
Crop Fields ◽  
Factors Influencing ◽  
Mayfield Method ◽  
Study Sites

Nesting success is defined as the percentage of nests that have at least one chick that successfully fledges from them. In this regard, this study was conducted in the Gangetic plain of district Raebareli (Uttar Pradesh), India, to investigate nesting success, resolve factors affecting the probability of nest failure and identify the predominant nest predators of the river lapwing, Vanellus duvaucelii. The line transect method was adopted to count the nesting pairs, while nesting success was estimated by the Mayfield method. Results revealed that river lapwing nests were not homogeneously distributed at the study sites. The number of nesting pairs significantly diverged at various study sites in different years. Nesting success of river lapwings at all habitat types varied across the year of study from 67.9% in 2016, to 63.6% and 70.1% in 2017 and 2018, respectively. In all years, river lapwing nests on open, unvegetated river banks achieved significantly greater nesting success than those in crop fields. However, nest failure was mainly due to predation (55%) and farming activity (32%). Furthermore, trampling (6%) by domestic cattles such as cows and buffaloes, egg non-viability (4%), human disturbance (2%) and flooding (1%) were reported as other notable factors influencing nest failure. We also found reptiles, birds and mammals as predators of eggs in the study areas. The most common predators were crow, dog, fox and snake. There is little information regarding factors influencing nesting success of river lapwings particularly in India and therefore this study increases our knowledge of this globally near-threatened species. Developing greater understanding of the river lapwing could help us to formulate effective conservation measures for this species.

scholarly journals Use of Survival Time Analysis to Analyze Nesting Success in Birds: An Example Using Loggerhead Shrikes

The Condor ◽  
2004 ◽  
Vol 106 (3) ◽  
pp. 457-471 ◽  
Author(s):  
Nadav Nur ◽  
Aaron L. Holmes ◽  
Geoffrey R. Geupel
Keyword(s):  
Survival Time ◽  
Failure Rate ◽  
Monitoring Program ◽  
Nesting Success ◽  
Laying Date ◽  
Time Analysis ◽  
Nest Failure ◽  
Kaplan Meier ◽  
Lanius Ludovicianus ◽  
Mayfield Method

AbstractOrnithologists commonly estimate nest survival using the Mayfield method, which produces relatively unbiased estimates provided that key assumptions are met. However, this method cannot statistically model nest failure in relation to quantitative variables, nor can it consider the joint effects of two or more independent variables. We demonstrate the use of an alternative method, survival time analysis. Survival time analysis can incorporate nests that are found at different points in the nesting cycle and nests whose ultimate outcome is unknown. The method allows one to examine variation in nest mortality during the course of the nesting period. To demonstrate this method we analyze data on Loggerhead Shrike (Lanius ludovicianus) nests, collected as part of a 3-year monitoring program of shrubsteppe habitat in north-central Oregon. We evaluate nesting success with respect to laying date, nest height, and annual variation in failure rate. We demonstrate three types of analyses: Kaplan-Meier estimation (a nonparametric method), Cox proportional hazards model (a semiparametric method), and Weibull parametric regression. Using these maximum-likelihood methods one can carry out likelihood-ratio tests and Akaike's Information Criterion model selection. The best predictive model included the effects of date and year. Nest failure rate changed during the nesting cycle and was heterogeneous among nests, thus violating assumptions of the Mayfield method. We discuss drawbacks to the use of logistic regression (another Mayfield alternative) to analyze nest success. Estimates of the age of a nesting attempt upon discovery are required for survival time analysis; we encourage ornithologists to collect such information.Uso del Análisis de Tiempo de Sobreviviencia para Analizar el Éxito de Nidificación: Un Ejemplo Utilizando Lanius ludovicianusResumen. Los ornitólogos generalmente utilizan el método de Mayfield para estimar la sobrevivencia de los nidos, un método que produce estimaciones relativamente poco sesgadas siempre y cuando se cumplan sus suposiciones claves. Sin embargo, este método no es capaz de modelar estadísticamente los fracasos de nidificación en relación con variables cuantitativas, ni tampoco puede considerar el efecto conjunto de dos o más variables independientes. Aquí, demostramos el uso de un método alternativo, el análisis de tiempo de sobrevivencia, el cual puede incorporar nidos que son encontrados en diferentes tiempos durante el ciclo de nidificación y también nidos cuyo resultado final es desconocido. El método permite examinar la variación en la mortalidad de nidos durante el transcurso del período de nidificación. Con el fin de demostrar este método, analizamos datos de nidos de Lanius ludovicianus colectados como parte de un programa de monitoreo del hábitat de estepa arbustiva durante un período de 3 años en Oregon nor-central. Evaluamos el éxito de nidificación con respecto a la fecha de puesta, altura del nido y variación anual en la tasa de fracaso. Demostramos tres tipos de análisis: estimación de Kaplan-Meier (un método no paramétrico), modelos de riesgo proporcional de Cox (un método semi paramétrico) y regresión paramétrica de Weibull. Utilizando estos métodos de máxima verosimilitud uno puede seleccionar modelos realizando pruebas de cocientes de verosimilitudes y utilizando el criterio de información de Akaike. El modelo con mayor capacidad predicativa incluyó los efectos de la fecha y el año. La tasa de fracaso de nidos varió durante el ciclo de nidificación y fue heterogénea entre nidos violando así, las suposiciones del método de Mayfield. Discutimos las desventajas del uso de regresiones logísticas (otra alternativa al método de Mayfield) para el análisis del éxito de los nidos. Para el análisis de tiempo de sobreviviencia se requiere la estimación de la edad de un intento de nidificación en el momento de ser descubierto, por lo que sugerimos a los ornitólogos colectar dicha información.

scholarly journals Uncertain Nest Fates in Songbird Studies and Variation in Mayfield Estimation

The Auk ◽  
2000 ◽  
Vol 117 (3) ◽  
pp. 615-626 ◽  
Author(s):  
James C. Manolis ◽  
David E. Andersen ◽  
Francesca J. Cuthbert
Keyword(s):  
Cox Regression ◽  
Survival Rates ◽  
Exposure Period ◽  
Potential Effect ◽  
Nesting Success ◽  
Seiurus Aurocapillus ◽  
Factors Affecting ◽  
Downward Bias ◽  
Empidonax Minimus ◽  
Mayfield Method

Abstract Determining whether nesting attempts are successful can be difficult. Yet, current protocols for estimating nesting success do not address how uncertain nest fates should be handled. We examined the problem of nest-fate uncertainty as it relates to Mayfield estimation of nesting success and in analyses of factors that influence success. We used data from Minnesota to illustrate the potential effect of uncertain fate; 40% of Ovenbird (Seiurus aurocapillus; n = 127) nests and 30% of Least Flycatcher (Empidonax minimus; n = 144) nests had uncertain fates. How this uncertainty is incorporated into Mayfield estimates of success varied widely among researchers. In a survey of researchers who use the Mayfield method, 9 of 22 respondents (of 40 contacted) excluded nests with uncertain fate. Excluding uncertain fates is counter to how Mayfield first described his estimator and can result in severe downward bias. The remaining respondents (59%) included nests with uncertain fate but varied in how they terminated the exposure period. We developed a simulation model that calculated Mayfield estimates using different approaches and compared them with a known rate of nesting success. Magnitude of bias in Mayfield estimates varied considerably in our simulations. The approach with the least bias terminated exposure with the last observed active date for nests with uncertain fate, and with the midpoint between last observed active and first observed inactive dates for nests with known fate. In addition, information necessary to interpret and compare Mayfield estimates often is not reported. These values, including variance estimates and the period lengths used to estimate survival rates, should be reported with Mayfield estimates. Finally, nest fate is commonly used as a categorical variable in studies of factors affecting nesting success. In this approach, however, nests with uncertain fate must be excluded. An alternative approach is Cox regression, which incorporates nests with uncertain fate.

Customer’s satisfaction on service quality at Vietnam Technological and Commercial Joint Stock Bank – An Giang Branch

2020 ◽  
Vol 4 (3) ◽  
pp. First
Author(s):  
Tran Minh Hieu ◽  
Nguyen Duong Ngoc Mai Chi
Keyword(s):  
Customer Satisfaction ◽  
Service Quality ◽  
Test Method ◽  
Quality Of Services ◽  
Factors Affecting ◽  
Factors Influencing ◽  
Alpha Reliability ◽  
Survey Results ◽  
Development Orientation

This study applied SERVQUAL scale of Parasuraman et al to measure factors affecting customer satisfaction on service quality at Vietnam Technological and Commercial Joint Stock Bank - An Giang Branch (Techcombank An Giang). The study was conducted to survey 207 customers who have been using the service at Techcombank An Giang. The survey results were analyzed by the Cronbach's Alpha reliability test method, then used Exploratory factor analysis (EFA) to verify and evaluate the scale of service quality. The results of the regression analysis show that customer's satisfaction about service quality at Techcombank An Giang includes four factors: The factor with the highest level is the Empathy with Beta = 0.253, the second of factor is the Responsibility with Beta = 0.248, ranked third in the influence level is the Tangible with Beta = 0.235, and the lowest impact level is the Reliability with Beta = 0.144. The research also uses statistical methods to describe and test the differences of demographic factors with customer's satisfactionon service quality.The analysis results show that there is no difference between customer's satisfaction on service quality and factors such as gender, age, income, number of transaction banks, regular transaction banks, and time to use the service at Techcombank An Giang. Through the research results, the author would like to propose some ideas to improve the quality of services, thereby attracting new customers and importantly, keeping traditional customers because the development orientation of Techcombank is to take care of old customers to cross sell other products of the bank. The Stud results offer a basis for the branch to identify the factors influencing customer satisfaction on their service quality, thereby having an appropriate strategy to improve customer satisfaction.

Factors Influencing Utilisation of Maternal Healthcare Services: Womens Perception

2015 ◽  
Vol 4 (1and2) ◽  
Author(s):  
Gyanvati
Keyword(s):  
Healthcare Services ◽  
Maternal Healthcare ◽  
Factors Affecting ◽  
Factors Influencing ◽  
Economic Background ◽  
Newborn Child

This paper analyses the factors affecting for utilization of maternal healthcare services. Following is the section wise description of the paper. Firstly, the paper looks into socio-economic background of women. Secondly, the paper focuses on usage of maternal healthcare services by women. Thirdly, the paper also traces the factors affecting for usage of maternal healthcare services. Lastly, the paper concludes and suggests by emphasizing the significance of proper utilization of maternal healthcare services that it leads to better health of mother and their newborn child.

Assessment of factors affecting short-term pulmonary functions following cardiac surgery: A prospective observational study

2021 ◽  
pp. 021849232110100
Author(s):  
Neetika Katiyar ◽  
Sandeep Negi ◽  
Sunder Lal Negi ◽  
Goverdhan Dutt Puri ◽  
Shyam Kumar Singh Thingnam
Keyword(s):  
Cardiac Surgery ◽  
Pulmonary Function ◽  
Forced Vital Capacity ◽  
Vital Capacity ◽  
Forced Expiratory Volume ◽  
Pulmonary Complications ◽  
Operative Morbidity ◽  
Factors Affecting ◽  
Factors Influencing ◽  
Significant Impairment

Background Pulmonary complications after cardiac surgery are very common and lead to an increased incidence of post-operative morbidity and mortality. Several factors, either modifiable or non-modifiable, may contribute to the associated unfavorable consequences related to pulmonary function. This study was aimed to investigate the degree of alteration and factors influencing pulmonary function (forced expiratory volume in one second (FEV1) and forced vital capacity), on third, fifth, and seventh post-operative days following cardiac surgery. Methods This study was executed in 71 patients who underwent on-pump cardiac surgery. Pulmonary function was assessed before surgery and on the third, fifth, and seventh post-operative days. Data including surgical details, information about risk factors, and assessment of pulmonary function were obtained. Results The FEV1 and forced vital capacity were significantly impaired on post-operative days 3, 5, and 7 compared to pre-operative values. The reduction in FEV1 was 41%, 29%, and 16% and in forced vital capacity was 42%, 29%, and 19% consecutively on post-operative days 3, 5, and 7. Multivariate analysis was done to detect the factors influencing post-operative FEV1 and forced vital capacity. Discussion This study observed a significant impairment in FEV1 and forced vital capacity, which did not completely recover by the seventh post-operative day. Different factors affecting post-operative FEV1 and forced vital capacity were pre-operative FEV1, age ≥60, less body surface area, lower pre-operative chest expansion at the axillary level, and having more duration of cardiopulmonary bypass during surgery. Presence of these factors enhances the chance of developing post-operative pulmonary complications.

scholarly journals Aphid–Plant–Phytovirus Pathosystems: Influencing Factors from Vector Behaviour to Virus Spread

Agriculture ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 502
Author(s):  
Junior Corneille Fingu-Mabola ◽  
Frédéric Francis
Keyword(s):  
Influencing Factors ◽  
Virus Transmission ◽  
Physical Factors ◽  
Factors Affecting ◽  
Vector Borne Diseases ◽  
Vector Behaviour ◽  
Crop Fields ◽  
Host Seeking ◽  
The Impact ◽  
Vector Efficiency

Aphids are responsible for the spread of more than half of the known phytovirus species. Virus transmission within the plant–aphid–phytovirus pathosystem depends on vector mobility which allows the aphid to reach its host plant and on vector efficiency in terms of ability to transmit phytoviruses. However, several other factors can influence the phytoviruses transmission process and have significant epidemiological consequences. In this review, we aimed to analyse the aphid behaviours and influencing factors affecting phytovirus spread. We discussed the impact of vector host-seeking and dispersal behaviours mostly involved in aphid-born phytovirus spread but also the effect of feeding behaviours and life history traits involved in plant–aphid–phytovirus relationships on vector performances. We also noted that these behaviours are influenced by factors inherent to the interactions between pathosystem components (mode of transmission of phytoviruses, vector efficiency, plant resistance, …) and several biological, biochemical, chemical or physical factors related to the environment of these pathosystem components, most of them being manipulated as means to control vector-borne diseases in the crop fields.

scholarly journals Spatial distribution of the Barbary Partridge (Alectoris barbara) in Sardinia explained by land use and climate

2021 ◽  
Vol 67 (4) ◽  
Author(s):  
Gianpasquale Chiatante ◽  
Marta Giordano ◽  
Anna Vidus Rosin ◽  
Oreste Sacchi ◽  
Alberto Meriggi
Keyword(s):  
Land Use ◽  
Conservation Status ◽  
Distance Sampling ◽  
Strong Relationship ◽  
European Population ◽  
Factors Affecting ◽  
Brood Rearing ◽  
Management Actions ◽  
Negative Effect ◽  
Study Sites

AbstractMore than half of the European population of the Barbary Partridge is in Sardinia; nonetheless, the researches concerning this species are very scarce, and its conservation status is not defined because of a deficiency of data. This research aimed to analyse the habitat selection and the factors affecting the abundance and the density of the Barbary Partridge in Sardinia. We used the data collected over 8 years (between 2004 and 2013) by spring call counts in 67 study sites spread on the whole island. We used GLMM to define the relationships between the environment (topography, land use, climate) both the occurrence and the abundance of the species. Moreover, we estimated population densities by distance sampling. The Barbary Partridge occurred in areas at low altitude with garrigue and pastures, avoiding woodlands and sparsely vegetated areas. We found a strong relationship between the occurrence probability and the climate, in particular, a positive relation with temperature and a negative effect of precipitation, especially in April–May, during brood rearing. Furthermore, dry crops positively affected the abundance of the species. We estimated a density of 14.1 partridges per km2, similar to other known estimates. Our findings are important both because they increase the knowledge concerning this species, which is considered data deficient in Italy, and because they are useful to plan management actions aimed to maintain viable populations if necessary.

scholarly journals Socioeconomic Risks and Their Impacts on Ecological River Health in South Korea: An Application of the Analytic Hierarchy Process

2021 ◽  
Vol 13 (11) ◽  
pp. 6287
Author(s):  
Suyeon Kim ◽  
Sang-Woo Lee ◽  
Se-Rin Park ◽  
Yeeun Shin ◽  
Kyungjin An
Keyword(s):  
South Korea ◽  
Socioeconomic Factors ◽  
Ecosystem Health ◽  
Relative Importance ◽  
River Ecosystem ◽  
River Health ◽  
Analytic Hierarchy ◽  
Factors Affecting ◽  
Factors Influencing ◽  
Hierarchy Process

It is imperative to develop a methodology to identify river impairment sources, particularly the relative impact of socioeconomic sources, to enhance the efficiency of various river restoration schemes and policies and to have an internal diagnosis system in place. This study, therefore, aims to identify and analyze the relative importance of the socioeconomic factors affecting river ecosystem impairment in South Korea. To achieve this goal, we applied the Analytical Hierarchy Process (AHP) to evaluate expert judgement of the relative importance of different socioeconomic factors influencing river ecosystem impairment. Based on a list of socioeconomic factors influencing stream health, an AHP questionnaire was prepared and administered to experts in aquatic ecology. Our analysis reveals that secondary industries form the most significant source of stream ecosystem impairment. Moreover, the most critical socioeconomic factors affecting stream impairment are direct inflow pollution, policy implementation, and industrial wastewater. The results also suggest that the AHP is a rapid and robust approach to assessing the relative importance of different socioeconomic factors that affect river ecosystem health. The results can be used to assist decision makers in focusing on actions to improve river ecosystem health.

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