Low survival rather than breeding success explains little penguin population decline on Granite Island

2015 ◽  
Vol 66 (11) ◽  
pp. 1057 ◽  
Author(s):  
Diane Colombelli-Négrel

Over the past decade, populations of little penguins (Eudyptula minor) have been seriously declining across South Australia for reasons still not fully understood. In the present study, I investigated breeding performance and return rates of little penguins on Granite Island for 17 years in relation to patterns of population decline. I focussed on the impacts of human disturbance, breeding site, abandonment and predation on breeding success. The average breeding success was 1.05±0.12 fledglings per pair; and breeding success increased since 1990, despite population decline. Breeding site was the main factor affecting breeding success. I found no effect of predation or abandonment on breeding success, but there was a negative effect of predation on the number of dead chicks found. In addition, I found a negative effect of human disturbance. Despite the observed increase in breeding success, return rates were extremely low for both adults (16.3%) and fledglings (2.3%). Population modelling confirmed the observed population decline on Granite Island, with subadult survival being the most critical variable affecting population growth. The present study thus highlighted the need for further studies into factors affecting survival of adults and subadults.

Ornis Svecica ◽  
2019 ◽  
Vol 29 ◽  
pp. 53-68
Author(s):  
N Erik I Nyholm

Return rates of 4,178 female and 1,565 male breeding Pied Flycatchers ringed in 1965–2017 were studied near the species’ upper elevation and climatic limit in northern Sweden. Female return rate was 7.5% in the season subsequent to the first breeding season. Having returned once, 37% continued to return the next three seasons. Corresponding return rates of males were 27% and 39%. Female return rate decreased with more than 30% during the study period whereas that of males did not decrease. This difference was probably due to increased mortality during the non-breeding season that selectively struck females after the 1970s. Local factors affected return rates in both sexes. Return rate was positively correlated with breeding success in females but negatively in males, whereas it was correlated with nest-predation in the opposite way. Predation by mustelids accounted for a significant part of female return rate. Females that had returned once were continuously faithful to the former breeding site. Males showed faithfulness only after having returned twice.


2021 ◽  
Vol 67 (4) ◽  
Author(s):  
Gianpasquale Chiatante ◽  
Marta Giordano ◽  
Anna Vidus Rosin ◽  
Oreste Sacchi ◽  
Alberto Meriggi

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.


2015 ◽  
Vol 743 ◽  
pp. 526-532 ◽  
Author(s):  
C.M. Jiang ◽  
J.J. Lu ◽  
L.J. Lu

Based on the originally unprocessed data from the Official Platform of“110”Alarming Receiving Center (OP110ARC) of Shanghai Public Security Bureau (SPSB), 529 single-vehicle crashes reported during one year and a half which happened at the thirteen urban road tunnels going across the Huangpu River are used in this study. To investigate the factors affecting the crash influence severity levels, ordered probit regression is established. Several categories of factors are considered as explanatory variables in the models. The study finds that the entrance of the tunnels is the site where severe injury crashes trend to occur. Rainy and snowy days impose vehicles and motorists driving via the tunnel sections in danger. Tunnels with a low speed limit (40 km/h in this study) may be not as safe as we thought before. Two-wheel vehicles without sufficient physical protection for its drivers and heavy vehicles also show a negative effect on the operation safety of single-vehicle at these studied tunnels. Alcohol involved drivers are more likely to suffer from a severe crashes and gets badly hurt.


Author(s):  
Fredy S. Monge-Rodríguez ◽  
He Jiang ◽  
Liwei Zhang ◽  
Andy Alvarado-Yepez ◽  
Anahí Cardona-Rivero ◽  
...  

COVID-19 has spread around the world, causing a global pandemic, and to date is impacting in various ways in both developed and developing countries. We know that the spread of this virus is through people’s behavior despite the perceived risks. Risk perception plays an important role in decision-making to prevent infection. Using data from the online survey of participants in Peru and China (N = 1594), data were collected between 8 July 31 and August 2020. We found that levels of risk perception are relatively moderate, but higher in Peru compared to China. In both countries, anxiety, threat perception, self-confidence, and sex were found to be significant predictors of risk perception; however, trust in the information received by government and experts was significant only in Peru, whereas self-confidence had a significant negative effect only for China. Risk communication should be implemented through information programs aimed at reducing anxiety and improving self-confidence, taking into consideration gender differences. In addition, the information generated by the government should be based on empirical sources. Finally, the implications for effective risk communication and its impacts on the health field are discussed.


2021 ◽  
Vol 13 (2) ◽  
pp. 947
Author(s):  
Shanshan Wu ◽  
Lucang Wang ◽  
Haiyang Liu

The development of tourism is based on tourism flow and studying a tourism flow network can help to elucidate its mechanism of operation. Transportation network is the path to realize the spatial displacement of tourism flow. This study used “Tencent migration” big data to explore the spatial distribution characteristics and rules of tourism flow in China, providing suggestions for the development of tourism. The results demonstrate that the 361 cities studied can be divided into three types: destination-oriented, tourist-origin-oriented, and destination-oriented and tourist-origin-oriented. There are significant differences in the quantity of flow, the area of concentration, and the factors affecting the flow in the three types of cities. The larger the flow of tourism between cities, the higher the network level, and the wider the network range. The high-level nodes are closely related, while the peripheral nodes are more widely distributed, with weak attractiveness and inconvenient traffic, forming a “core-edge” structure. Different network patterns are established for different modes of transportation. The degree of response of different types of transportation to distance is the main factor influencing the network patterns of diverse paths. These findings have practical implications for the choice of appropriate travel destinations and transportation modes for tourists.


2018 ◽  
Vol 53 ◽  
pp. 01012 ◽  
Author(s):  
Wei Pan ◽  
Caijia Lei ◽  
Wei Jia ◽  
Hui Gao ◽  
Binghua Fang

Regarding analysis of load characteristics of a power grid, there are multiple factors that influence the variation of load characteristics. Among these factors, the influence of different ones on the change of load characteristic is somewhat different, thus the degree of influence of various factors needs to be quantified to distinguish the main and minor factors of load characteristics. Based on this, the grey relational analysis in the grey system theory is employed as the basis of mathematical model in this paper. Firstly, the main factors affecting the load characteristics of a power grid are analysed. Then, the principle of quantitative analysis of the influencing factors by using grey relational grade is introduced. Lastly, the load of Guangzhou power grid is selected as the research object, thereby the main factor of temperature affecting the load characteristics is quantitatively analysed, such that the correlation between temperature and load is established. In this paper, by investigating the influencing factors and the degree of influence of load characteristics, the law of load characteristics changes can be effectively revealed, which is of great significance for power system planning and dispatching operation.


Author(s):  
Devendra Kumar Verma ◽  
Hari Singh ◽  
Girdhari lal Meena ◽  
Jitendra Suman ◽  
Sharad Sachan

Background: Pulses are one of the most important food crops grown globally owed to their higher protein content. It also accounts for larger financial gains of the agricultural sector by amounting for a large part of the exports. The present study was carried out to determine the factors affecting production of pulse crops in Rajasthan. Methods: This paper based on secondary data collected over the years i.e. from 2000-01 to 2017-18. The Cobb-douglas production function was used to the observation for the estimation of elasticity of selected variables contributing to the production of pulses in Rajasthan state, Cobb douglas type production function was employed to assess the effects of seed, fertilizer, manure, human labour, irrigation, bullock labour and plant protection measures on pulses production. Result: The results from the study have shown that fertilizer and plant protection measures were positively significant while the variable corresponding to irrigation water was negatively significantly affecting the gram production. The variables such as seed and irrigation water were found positive and significant, while plant protection measures had significant negative effect on black gram production. Only two variables namely, fertilizer and irrigation water were found positively significant out of estimating production function of green gram.


2018 ◽  
Vol 1 (1) ◽  
pp. 42-57
Author(s):  
Rodika Wakerkwa ◽  
Syaikhul Fallah ◽  
Otniel Safkaur

This study examines factors affecting the interest of state civil servants to undertake whistle-blowing action on local governments of Papua Province. The population in this study is the State Civil Servants (ASN) on local governments of Papua Province, with 120 number of people as sample in this research. Multiple regression analysis techniques is used to analysis, discuss and testing the hypothesis from the data collection. This research find that variabel of organization commitment has a significant and negative effect on the interest of state civil servants to undertake Whistle Blowing action. Thus it can be explained that, in high and low commitment of organzation environment which dominated by employees at SKPDs in government of Jayapura city that have lowered interest to undertake Whistle Blowing action. Then, varibale of Attitude has a significant effect on the Interest of Whistle Blowing action, which the attitude of the existing employees will increase the interest to Blow the Whistle at the SKPDs’ employees in the government of Jayapura city. Similarly, Personal Cost variabel has a significant affect on the interest of state civil servants to attempt a Whistle Blowing action, it can be seen that when there is a sufficient personal cost in the employees of SKPD in the government of Jayapura city, it will increase the interest in Blowing the Whistle. While, the degree of seriousness also has a significant influence on the employees to attempt a Whistle Blowing interest. This means that the increasing interest in Blowing Whistle among employees are required to enhance the degree of seriousness in conducting Interest of Blowing a Whistle at SKPD in the government of Jayapura city.


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