Search published articles


Showing 3 results for Sagar
Study of winter avifauna diversity from a man-made reservoir in the West Bengal, India
Debayan Gayen, Biswajit Mukherjee, Sanchari Sarkar, Bappa Goswami, Sagar Adhurya, Moitreyee Chakrabarty,
Volume 4, Issue 1 (3-2022)
Abstract
The present study was conducted to determine the winter avifauna diversity of the Bakreswar Reservoir, Birbhum district, West Bengal from November 2017 to February 2021 using point count and opportunistic spotting. A total of 174 species of birds belonging to 18 orders, 47 families and 115 genera were noted during the study of which the family Anatidae was the most dominant family with 21 species, followed by the Accipitridae with 19 species, and the Motacillidae and Ardeidae with 10 species each. The Lesser whistling teal Dendrocygna javanica, Red-crested pochard Netta rufina and Bar-headed goose Anser indicus were the most abundant species during the winter months. Four Vulnerable species and five Near Threatened species were also recorded in the study area. Various diversity indices indicated that the species assemblage in 2019–2020 was more diverse than other years. Some species, such as the Common shelduck Tadorna tadorna (Linnaeus, 1758), Swinhoe’s minivet Pericrocotus cantonensis Swinhoe, 1861, Eurasian sparrowhawk Accipiter nisus (Linnaeus, 1758), Pallas’ gull Ichthyaetus ichthyaetus (Pallas, 1773), Black-headed gull Chroicocephalus ridibundus (Linnaeus, 1766), Hen harrier Circus cyaneus (Linnaeus, 1766) and Bonelii’s eagle Aquilla fasciata Vieillot, 1822, are recorded for the first time from this region. Various threats like habitat destruction, habitat degradation and hunting of migratory and threatened birds pose the major problems in the study location.

Diversity and population trends of waterbirds at Lake-2, the Ballavpur Wildlife Sanctuary, West Bengal State, India
Sagar Adhurya, Debayan Gayen, Suvendu Das, Santanu Ray,
Volume 4, Issue 1 (3-2022)
Abstract
The focus of the present study was (i) to develop a complete checklist, (ii) to find the seasonal variation of waterbird diversity, and (iii) to assess the population trends of different waterbirds at Lake-2 of the Ballavpur Wildlife Sanctuary (BWLS), Birbhum District, West Bengal, India. The study was carried out from January 2018 to November 2019. All waterbirds spanning in the freshwater lake were counted with field binoculars and digital cameras. The bird count data were used to calculate different biodiversity indices (such as Shannon-Weiner diversity index, Simpson’s Diversity Index etc.). Further, we assessed the population trends of different waterbirds with the data available from eBird. A total of 32 waterbird species belonging to 27 genera, 9 families and 8 orders were recorded during the present study. Dendrocygna javanica (Horsfield) was found to be the most dominant species throughout the year. Maximum richness and abundance were recorded during the winter months (December to February), whereas the highest species diversity was recorded during the monsoon months (March to June). The present study further establishes that both the richness and abundance of the waterbirds at BWLS have increased as compared to the past data. However, various species of wading waterbirds that were recorded previously were not observed during the present study. Moreover, the population trend analysis revealed a strong decline in the population of Mareca strepera (Linnaeus) and a moderate increase in the population of Ardeola grayii (Sykes). Thus, the present study concludes that BWLS supports high waterbird diversity irrespective of its small area.

Cyprinid (Teleostei: Cypriniformes) diversity and assemblage in south-central Bhutan
Laxmi Sagar, Dhan Bdr Gurung, Karma Wangchuk, Karma L. Wangmo, Rinchen Dorji, Tshering Zangmo, Rupesh Subedi,
Volume 5, Issue 4 (10-2023)
Abstract
Cyprinidae (Teleostei: Cypriniformes) is the predominate family among Bhutan's freshwater fishes, yet significant gaps exist in the knowledge of their diversity and assemblage. Cyprinids were sampled from 54 plots across four river basins (Aiechhu, Jaldakachhu, Mangdechhu, and Punatsangchhu) using systematic sampling at an interval of 5 km. A total of 850 individuals belonging to 22 species and 13 genera were recorded. Aiechhu had the highest diversity and evenness (H’= 1.66±0.28, J’= 0.95±0.03), followed by Punatsangchhu (H’= 1.58±0.34, J’= 0.94±0.04). Meanwhile, Jaldakachhu and Mangdechhu exhibited the lowest diversity and evenness (H’= 0.90±0.66, J’= 0.84±0.54 and H’= 0.54±0.70, J’= 0.38±0.49, respectively). There was a significant difference in diversity among river basins (χ2 (3)= 20.98, p < 0.001) with specific variation between Mangdechhu and Punatsangchhu (Z= 3.80, p= 0.00), Mangdechhu and Aiechhu (Z= 3.35, p= 0.01), and Jaldakachhu and Punatsangchhu (Z= 2.83, p= 0.03). Canonical correspondence analysis indicated that cyprinid assemblage was significantly correlated with environmental variables (r= 0.94, p= 0.001 in axis 1 and r= 0.82, p= 0.001 in axis 2) explaining 77% of variance. Axis 1 was positively correlated with temperature (r= 0.92), total dissolved solids (r= 0.53), conductivity (r= 0.51), and salinity (r= 0.39) and negatively correlated with elevation (r= −0.69). Axis 2 was negatively correlated with total hardness (r= −0.82) and dissolved oxygen (r= −0.65). Cluster analysis identified three clusters based on dominant species. Further studies exploring other river basins of Bhutan are needed to better understand the ecological dynamics of cyprinids in Bhutan.

Page 1 from 1     

  | Journal of Animal Diversity

Designed & Developed by : Yektaweb