Mortality of sarus cranes (Grus antigone) due to electricity wires in Uttar Pradesh, India

2005 ◽  
Vol 32 (3) ◽  
pp. 260-269 ◽  
Author(s):  
K.S.G. SUNDAR ◽  
B.C. CHOUDHURY

Although overhead electrical wires are known to have caused severe declines of bird populations, there are no studies in India that address this danger, even for endangered species. Rates of mortality, factors affecting mortality and population effects of electrical wires on the globally endangered sarus crane (Grus antigone) were assessed for breeding and non-breeding cranes in Etawah and Mainpuri districts, Uttar Pradesh, India. Non-breeding cranes were most susceptible to wires and, within territories, mortalities were higher for pre-dispersed young. Similar proportions of non-breeding and breeding cranes were killed, together accounting for nearly 1% of the total sarus crane population annually. Supply wires accounted for the majority of sarus crane deaths, and only non-breeding cranes were killed by both supply and high-tension power lines. Non-breeding crane deaths at roost sites were correlated with numbers of roosting birds and numbers of wires at each site. Over 40% of 251 known sarus crane territories had at least one overhead wire posing a risk to breeding adults and pre-dispersed young. A risk index for wires over territories of cranes was computed; mortality was not affected by increasing the number and therefore risk posed by wires. Most crane deaths in territories occurred as a result of wires at edges of territories. Wires around roosting sites, territoriality and age of sarus cranes appear to be the most important factors affecting their mortality due to wires. Mitigation measures will be most effective around roost sites and for wires that border territories of breeding pairs.

1991 ◽  
Vol 155 (5) ◽  
pp. 347-347 ◽  
Author(s):  
Raymond M Lowenthal ◽  
Jean B Panton ◽  
Margaret J Baikie ◽  
J Norelle Lickiss

1979 ◽  
Vol 111 (11) ◽  
pp. 1299-1306 ◽  
Author(s):  
N. L. Bazinet ◽  
M. K. Sears

AbstractMortality factors affecting populations of the leafminers Argyresthia thuiella (Pack.) and Pulicalvaria thujaella (Kft.), on eastern white cedar in the area of Guelph, Ontario were identified and summarized in life tables. During the two annual generations studied from 1975 to 1977, overwintering mortality varied widely. Winterkill increased from 6.8% to 62.9% for A. thuiella and from 8.1% to 54.6% for P. thujaella, from 1976 to 1977. Several parasitoids produced substantial mortality of each host species, but their effect may have been superseded by winterkill in 1977. Data indicate that both populations of leafminers increased from 1975 to 1976 but decreased substantially from 1976 to 1977.


2003 ◽  
Vol 18 (2) ◽  
pp. 109-114 ◽  
Author(s):  
Steven J. Stein ◽  
Diana N. Kimberling

Abstract Information on the mortality factors affecting naturally seeded conifer seedlings is becoming increasingly important to forest managers for both economic and ecological reasons. Mortality factors affecting ponderosa pine (Pinus ponderosa) seedlings immediately following natural germination and through the following year were monitored in Northern Arizona. The four major mortality factors in temporal order included the failure of roots to establish in the soil (27%), herbivory by lepidopteran larvae (28%), desiccation (30%), and winterkill (10%). These mortality factors were compared among seedlings germinating in three different overstory densities and an experimental water treatment. Seedlings that were experimentally watered experienced greater mortality than natural seedlings due to herbivory (40%), nearly as much mortality due to the failure of roots to establish in the soil (20%), less mortality due to winterkill (5%), and no mortality due to desiccation. The seedling mortality data through time were summarized using survivorship curves and life tables. Our results suggest that managers should consider using prescribed burns to decrease the percentage of seedlings that die from failure of their roots to reach mineral soil and from attack by lepidopteran larvae. West. J. Appl. For. 18(2):109–114.


2012 ◽  
Vol 12 (S1) ◽  
Author(s):  
Sangeeta Kansal ◽  
Shyam Sundar ◽  
Madhukar Rai ◽  
Narendra Kumar Tiwary ◽  
Jaya Chakravarty

2007 ◽  
Vol 97 (5) ◽  
pp. 445-453 ◽  
Author(s):  
S. Girardoz ◽  
R. Tomov ◽  
R. Eschen ◽  
D.L.J. Quicke ◽  
M. Kenis

AbstractThe horse-chestnut leaf miner, Cameraria ohridella, is an invasive alien species defoliating horse-chestnut, a popular ornamental tree in Europe. This paper presents quantitative data on mortality factors affecting larvae and pupae of the leaf miner in Switzerland and Bulgaria, both in urban and forest environments. Two sampling methods were used and compared: a cohort method, consisting of the surveying of pre-selected mines throughout their development, and a grab sampling method, consisting of single sets of leaves collected and dissected at regular intervals. The total mortality per generation varied between 14 and 99%. Mortality was caused by a variety of factors, including parasitism, host feeding, predation by birds and arthropods, plant defence reaction, leaf senescence, intra-specific competition and inter-specific competition with a fungal disease. Significant interactions were found between mortality factors and sampling methods, countries, environments and generation. No mortality factor was dominant throughout the sites, generations and methods tested. Plant defence reactions constituted the main mortality factor for the first two larval stages, whereas predation by birds and arthropods and parasitism were more important in older larvae and pupae. Mortality caused by leaf senescence was often the dominant mortality factor in the last annual generation. The cohort method detected higher mortality rates than the grab sampling method. In particular, mortality by plant defence reaction and leaf senescence were better assessed using the cohort method, which is, therefore, recommended for life table studies on leaf miners.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sucheta Agarwal ◽  
Veland Ramadani ◽  
Leo-Paul Dana ◽  
Vivek Agrawal ◽  
Jitendra Kumar Dixit

Purpose The ascent of women enterprising community (WEC) in a couple of decades draws the attention of various government and non-government bodies. Literature has mentioned various studies that focus on the factors affecting the success or failure of women entrepreneurs (WEs), but understanding of the ranking of the factors depending on the experiences of different WEs is needed. This study aims to identify the significant factors essential for the growth of WEC. Design/methodology/approach This study examines the factors through interview of 33 WEs having different entrepreneurial experiences (less than 1 year, more than 1 year but less than 10 years and more than 10 years of experiences) from different regions of Uttar Pradesh, India, and with the help of analytical hierarchical process, ranks the factors affecting the sustainable growth of WEs. Findings Through analysis, significant factors have been identified such as determination, education, entrepreneurial resilience, personal satisfaction and provide employment, and these factors have been analysed according to the different experiences of WEs. An investigation of ranking these factors of WEC, especially in the emerging nations, can assist policymakers in designing projects that improve the mindfulness associated with women enterprise and define the compelling methodologies. Practical implications The growth of the WEC is significantly affected by gender orientation ways of thinking as driven by entrepreneurship models. Originality/value This study gives a direction to policymakers by emphasizing on significant factors of various stages of enterprise development for the encouragement of WEs in the emerging economies.


Oryx ◽  
2020 ◽  
pp. 1-10 ◽  
Author(s):  
Ana Teresa Marques ◽  
Ricardo C. Martins ◽  
João Paulo Silva ◽  
Jorge M. Palmeirim ◽  
Francisco Moreira

Abstract Collision with power lines is a major cause of mortality for many bird species. Understanding the biotic and abiotic factors that increase collision risk is therefore important for implementing mitigation measures to minimize mortality, such as power line rerouting or wire marking. Here, we used collision events registered during 2003–2015 along 280 km of transmission power lines in southern Portugal to analyse spatio-temporal patterns and collision risk factors in two sympatric, threatened, and collision-prone species: the great bustard Otis tarda and the little bustard Tetrax tetrax. The occurrence of collisions was not uniform across space and time, and variations could be explained by the species' ecological requirements, distribution patterns and behaviour. Although both species fly considerable distances between areas of suitable habitat, collisions were far more likely in power line sections with > 20% (for the little bustard) or > 50% (for the great bustard) of open farmland habitat in the surroundings. Power line configuration was also important: taller pylons and those with a higher number of wire levels posed a higher risk for both species. Wire marking had a small but significant effect for the little bustard, reducing collisions risk. There was, however, no similar effect for the great bustard, possibly a result of limited data. Mitigation measures should be implemented to prevent bustard collisions, including adequate route planning, ideally avoiding areas with > 20% of open habitat. Line configuration and wire marking are particularly important where such localities cannot be avoided and power lines cross areas with a high proportion of bustard habitat, including outside protected areas.


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