scholarly journals Using community-based interviews to determine population size, distribution and nest site characteristics of Pallas's fish eagle in north-east Bangladesh

Oryx ◽  
2021 ◽  
pp. 1-9
Author(s):  
Sayam U. Chowdhury ◽  
Mohammod Foysal ◽  
Nazim Uddin Khan

Abstract Pallas's fish eagle Haliaeetus leucoryphus was recategorized from Vulnerable to Endangered on the IUCN Red List in 2017 because of evidence that there is only a single population, which is declining as a result of continuous, widespread loss and degradation of freshwater wetlands. To determine the species’ status in Bangladesh, we conducted a large-scale community-based interview survey in north-east Bangladesh in 2017–2020. We also examined nest site habitat characteristics through field surveys and remotely sensed data. We conducted a total of 955 interviews in an area of 4,150 km2, through which we were able to determine the presence of 53 breeding pairs at a mean density of 1.2 nests per 100 km2. There was a higher nest density (3.7–4.8 nests per 100 km2) in some locations, which we identify as priority conservation areas. The majority of nests (62.2%) were close together and on tall trees with an open canopy structure. Nests were located within or close to (< 100 m) human settlements, and within 500 m of wetlands and rivers. Felling of nest trees, removal of nests by local people and loss of permanent wetlands (14.6% during 2010–2020) appeared to be the main threats. High nesting density in our study area suggests that the freshwater wetlands in north-east Bangladesh possibly hold the largest population of Pallas's fish eagle globally.

1998 ◽  
Vol 76 (5) ◽  
pp. 910-915 ◽  
Author(s):  
Heidi M Regehr ◽  
Michael S Rodway ◽  
William A Montevecchi

We investigated the relationship between nest-site characteristics and breeding performance of Black-legged Kittiwakes (Rissa tridactyla) on Great Island, Newfoundland, during 2 years of extreme predation pressure. The nest-site feature most consistently associated with egg and chick survival was rock overhang above the nest. The presence of rock projections beside nests was positively correlated with success in 1993, and rock protrusions below the nest were not associated with breeding success in either year. Central position in the colony was positively correlated and nest density negatively correlated with success in 1992. Consistent differences in chick production among colony regions reflected differences in large-scale cliff structure and predator accessibility. This study implicates large- and fine-scale aspects of nest-site selection by Black-legged Kittiwakes, with large-scale cliff structure being the most important.


2004 ◽  
Vol 14 (S1) ◽  
pp. S39-S52 ◽  
Author(s):  
APARAJITA DATTA ◽  
G. S. RAWAT

Nest-site selection by the sympatric Great Hornbill Buceros bicornis, Wreathed Hornbill Aceros undulatus and Oriental Pied Hornbill Anthracoceros albirostris was investigated in a lowland tropical forest in Arunachal Pradesh, north-east India during 1997–2000. Information on two nests of Rufous-necked Hornbill Aceros nipalensis in higher-elevation forests is also presented. All species nested in live trees of three tree genera, 83% (n = 36) in Tetrameles nudiflora, an emergent deciduous softwood, relatively common in lowland foothill forests. No difference was recorded in nest-tree species or nesting habitats of sympatric hornbills, but there were a few differences in structural characteristics of nest-trees. Cavity size was the main variable separating the three species. Great Hornbills used larger cavities while Oriental Pied Hornbills used smaller cavities closer to riverine areas. Nesting was attempted at 64% of known sites and successful fledging of chicks was 80% overall (n = 72 nests, pooled over 4 years). Nest-trees in disturbed habitats near human habitation were used but were often abandoned or unsuccessful and 50% of all nest-trees were inactive by the end of the study. Potential large nest-trees had a density of 5.9/ha, that of the two most used species was 1.3/ha, and minimum nest densities of all three species was about 1 pair/km2. Interference competition for nest-sites was not observed, despite similarity in nest-tree characteristics, low nest density and high loss of nest-trees. Nest-site availability may naturally limit hornbill populations in the area, and additional loss of nesting habitat to human activities may exacerbate limited availability of breeding sites.


2020 ◽  
Vol 91 (6) ◽  
pp. AB591-AB592
Author(s):  
Ratha-Korn Vilaichone ◽  
Natsuda Aumpan ◽  
Tomohisa Uchida ◽  
Thawee Ratanachu-ek ◽  
Lotay Tshering ◽  
...  

2020 ◽  
Vol 26 (2) ◽  
Author(s):  
Alessandro Belmonte

AbstractThis paper investigates the consequences for inter-group conflicts of terrorist attacks. I study the 2015 Baga massacre, a large scale attack conducted by Boko Haram at the far North-East state of Borno, Nigeria, as a quasi-natural experiment and examine a set of attitudes in the aftermath of the event of Christians and Muslims throughout the country. Comparing individuals, outside the region of Borno, interviewed by Afrobarometer immediately after the massacre and those interviewed the days before within same regions and holding fixed a number of individual characteristics, I document that the informational exposure to the event rendered Christians less amiable to neighboring Muslims and Muslims less likely to recognize the legitimacy of the state. Nonetheless, Muslims increased their view of the elections as a device to remove leaders in office, event that took place 2 months later with the election of the challenger, Muhammadu Buhari. My findings indicate that terrorist attacks may generate a relevant and heterogeneous backlash across ethnic groups.


2021 ◽  
Vol 13 (2) ◽  
pp. 176
Author(s):  
Peng Zheng ◽  
Zebin Wu ◽  
Jin Sun ◽  
Yi Zhang ◽  
Yaoqin Zhu ◽  
...  

As the volume of remotely sensed data grows significantly, content-based image retrieval (CBIR) becomes increasingly important, especially for cloud computing platforms that facilitate processing and storing big data in a parallel and distributed way. This paper proposes a novel parallel CBIR system for hyperspectral image (HSI) repository on cloud computing platforms under the guide of unmixed spectral information, i.e., endmembers and their associated fractional abundances, to retrieve hyperspectral scenes. However, existing unmixing methods would suffer extremely high computational burden when extracting meta-data from large-scale HSI data. To address this limitation, we implement a distributed and parallel unmixing method that operates on cloud computing platforms in parallel for accelerating the unmixing processing flow. In addition, we implement a global standard distributed HSI repository equipped with a large spectral library in a software-as-a-service mode, providing users with HSI storage, management, and retrieval services through web interfaces. Furthermore, the parallel implementation of unmixing processing is incorporated into the CBIR system to establish the parallel unmixing-based content retrieval system. The performance of our proposed parallel CBIR system was verified in terms of both unmixing efficiency and accuracy.


Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 3982
Author(s):  
Giacomo Lazzeri ◽  
William Frodella ◽  
Guglielmo Rossi ◽  
Sandro Moretti

Wildfires have affected global forests and the Mediterranean area with increasing recurrency and intensity in the last years, with climate change resulting in reduced precipitations and higher temperatures. To assess the impact of wildfires on the environment, burned area mapping has become progressively more relevant. Initially carried out via field sketches, the advent of satellite remote sensing opened new possibilities, reducing the cost uncertainty and safety of the previous techniques. In the present study an experimental methodology was adopted to test the potential of advanced remote sensing techniques such as multispectral Sentinel-2, PRISMA hyperspectral satellite, and UAV (unmanned aerial vehicle) remotely-sensed data for the multitemporal mapping of burned areas by soil–vegetation recovery analysis in two test sites in Portugal and Italy. In case study one, innovative multiplatform data classification was performed with the correlation between Sentinel-2 RBR (relativized burn ratio) fire severity classes and the scene hyperspectral signature, performed with a pixel-by-pixel comparison leading to a converging classification. In the adopted methodology, RBR burned area analysis and vegetation recovery was tested for accordance with biophysical vegetation parameters (LAI, fCover, and fAPAR). In case study two, a UAV-sensed NDVI index was adopted for high-resolution mapping data collection. At a large scale, the Sentinel-2 RBR index proved to be efficient for burned area analysis, from both fire severity and vegetation recovery phenomena perspectives. Despite the elapsed time between the event and the acquisition, PRISMA hyperspectral converging classification based on Sentinel-2 was able to detect and discriminate different spectral signatures corresponding to different fire severity classes. At a slope scale, the UAV platform proved to be an effective tool for mapping and characterizing the burned area, giving clear advantage with respect to filed GPS mapping. Results highlighted that UAV platforms, if equipped with a hyperspectral sensor and used in a synergistic approach with PRISMA, would create a useful tool for satellite acquired data scene classification, allowing for the acquisition of a ground truth.


Water Policy ◽  
2016 ◽  
Vol 18 (4) ◽  
pp. 862-876
Author(s):  
Jianwei Liu ◽  
Limin Kou ◽  
Qiang Zhou

In order to alleviate the water supply–demand problem, a flood resource utilization strategy is proposed, called ‘Flood Utilization’. The strategy focuses on building large-scale water conservancy facilities and improving management measures. This paper presents the probability analysis of floodwater utilization in a confluence area, where a tributary joins a main river. Baicheng is used as the study area, where the Taoer River joins the Nenjiang River. After a large number of analyses, the main results and conclusions are as follows: First, the upper limit of available floodwater corresponds to the Taoer River's flood with a 5% probability of occurrence. Secondly, there are compensation characteristics between the two rivers which mean that the Nenjiang River can supply water to the Taoer River area. The analysis of monthly runoff, shows that there are compensation characteristics in 50.9% of the data period. The compensation rates (CRs) for the months from June to October are 0.2, 0.27, 0.25, 0.27, and 0.2, respectively. Thirdly, the differences in the runoff characteristics show that it is suitable for floodwater utilization. Finally, it is proposed that floodwater utilization measures are based on local conditions, such as the regional water storage characteristics and the runoff characteristics of the two rivers, and should be applied for different periods.


2013 ◽  
Vol 1 (2) ◽  
pp. 96-114 ◽  
Author(s):  
Isabelle Buchstaller ◽  
Seraphim Alvanides

The aims of this paper are twofold. First, we locate the most effective human geographical methods for sampling across space in large-scale dialectological projects. We propose two geographical concepts as a basis for sampling decisions: Geo-demographic classification, which is a multidimensional method used for the socio-economic grouping of areas; we also develop an updated version of functional regions that can be used in sociolinguistic research. We then report on the results of a pilot project that applies these models to collect data regarding the acceptability of vernacular morphosyntactic forms in the North East of England. Following the method of natural breaks advocated for dialectology by Horvath & Horvath (2002), we interpret breaks in the probabilistic patterns as areas of dialect transitions. This study contributes to the debate about the role and limitations of spatiality in linguistic analysis. It intends to broaden our knowledge about the interfaces between human geography and dialectology.


2021 ◽  
pp. 1-14
Author(s):  
Jason Doyle ◽  
Kevin Filo ◽  
Alana Thomson ◽  
Thilo Kunkel

Delivering community-based benefits is oftentimes cited to justify the high costs associated with hosting large-scale events. The current research is embedded in positive psychology to examine how an event impacts host community members’ PERMA domains, reflected through positive emotions, engagement, relationships, meaning, and accomplishment. Adopting a longitudinal approach, the authors interviewed 15 host community members before and after a large-scale sport event to determine if and how the event impacted their well-being. The findings uncovered evidence that the event activated positive emotions, relationships, and meaning across both phases, and evidence of accomplishment within the postevent phase. The findings contribute to the knowledge by examining the links between large-scale sport events and well-being throughout the event lifecycle. This research forwards implications for event bidding committees, event organizers, and host community officials to maximize community well-being through hosting large-scale events and to help justify associated expenses from a social–psychological perspective.


Sign in / Sign up

Export Citation Format

Share Document