فهرست مطالب

  • Volume:4 Issue: 1, Mar 2022
  • تاریخ انتشار: 1401/08/22
  • تعداد عناوین: 8
  • Sujan Bohara, Rajeev Joshi, Bishow Poudel* Pages 1-17

    The Gharial (Gavialis gangeticus), also known as the gavial or fish-eating crocodile, is a member of the family Gavialidae, is the most threatened of the two species of crocodilians found in Nepal. However, sufficient information on its habitat characteristics influencing population status, distribution, and threats to its existence are lacking. We studied the gharial population in the Narayani River that was carried out in the winter season during December 2019 to April of 2020. During our surveys, a total of 117 gharials were recorded, including an adult male, 56 adult females, 19 sub-adults, 32 immature and nine were unidentified. The gharial census recorded 57 gharials in Sikrauli-Amaltari (Chitwan branch) river section followed by 14 in Sikrauli-Amaltari (Nawalparasi branch), 16 in Amaltari-Baguwan and 30 in the Baguwan-Tribeni River sections. Of 117 individuals, the number of gharials sighted under the direct observation category was 112. The majority of respondents (129 of 140) during our questionnaire, considered gharial as an important species and displayed a favorable attitude towards gharial conservation. This study concludes that the population of gharial in the Narayani River has increased, as the present population is larger than recorded during previous surveys. Finally, regular surveys and monitoring of gharial in the area are recommended to investigate the status of gharial, the prevalence of any threats and disturbance along the habitat of this important species.

    Keywords: Climate change, conservation, disturbance, habitats, threats
  • Spartaco Gippoliti* Pages 18-20

    Many users of taxonomic lists believe them to be based on consistent data, but this is rarely true, and biased knowledge may be the rule rather than the exception. In the present essay on the taxonomy of primates of the Horn of Africa, I show how taxonomic history has consequences for the present appreciation of primate diversity in the region, and thus in directing conservation efforts. To minimize future losses, it is necessary that international bodies recognize taxonomic checklists as works in progress, eventually encouraging further integrated approaches to taxa delimitation.

    Keywords: Colobus guereza, Ethiopia, gelada, IUCN Red List, Somalia, subspecies, superspecies
  • Rishi Baral*, Yadav Ghimirey, Basudev Neupane, Baburam Lamichhane, Santosh Bhattarai, Karan Bahadur Shah Pages 21-26

    Four specimens of the Large-toothed Ferret Badger Melogale personata I. Geoffroy Saint-Hilaire were found at separate sites in Marshyangdi Rural Municipality, Ward No 4, Srichaur, Tangring, Lamjung district, Nepal. The first individual was captured alive by local people on 4th January 2017 and the second was found dead on 17th January 2017. The third alive and fourth road-killed specimens of M. personata were photographed from Marshyangdi Rural Municipality, on 9th July 2020, 26th November 2021, respectively. The species was recorded at the border region of the Annapurna Conservation Area, approximately 203 km from Kathmandu in a tropical forest alongside the Marshyangdi River. The specimens were examined carefully and identified on a morphological basis. The present account represents the first authentic record of M. personata in the Annapurna Conservation Area, moreover also for Nepal.

    Keywords: Distribution, Lamjung, Marshyangdi Rural Municipality, new record, tropical
  • Laxmi Prasad Upadhyaya, Naresh Pandey*, Laxman Khanal Pages 27-40

    The Kathmandu Valley, encompassing the capital city of Nepal, is one of the fastest growing metropolitan areas in South Asia. Rapid population growth and urbanization in Kathmandu have degraded the urban environment affecting the native biota. Therefore, a detailed assessment of avian species richness and its distribution in potential green spaces of the Kathmandu Valley is essential. We assessed the avian diversity in different habitats of the Tribhuvan University area, a potential refuge for birds in the urban landscape, by the point count method in the winter and summer of 2020. A total of 71 bird species from 39 genera and 32 families comprising 10 orders - ‘including the globally endangered Steppe eagle (Aquila nipalensis)’ - were recorded. Of the 10 orders, Passeriformes (44 species), had the highest richness followed by Columbiformes, Piciformes and Cuculiformes (with four species in each). Among the feeding guilds, the insectivorous guild (with 28 species) had the highest species richness followed by omnivores and carnivores. A higher Shannon’s diversity index was recorded in forest habitats (3.51) than built-up areas (3.45) or farmland (3.42). Despite the small size, our study has shown that the Tribhuvan University area is an important greenspace for birds in the Kathmandu Valley. An extensive exploration, monitoring and management of greenspaces are crucial for maintaining the ecological integrity of the urban landscape of the Kathmandu Valley.

    Keywords: Avian fauna, greenspace, Kirtipur, Passeriformes, urbanization
  • Sagar Adhurya*, Debayan Gayen, Suvendu Das, Santanu Ray Pages 41-51

    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.

    Keywords: Aquatic avifaunal diversity, diversity indices, wetland-dependent birds
  • Paromit Chatterjee, Kamalika Bhattacharyya*, Silanjan Bhattacharyya Pages 52-57

    We present the first confirmed report of the Long-snouted Bhutan Squirrel Dremomys lokriah bhotia from the state of West Bengal, India. Previously the subspecies was known from limited localities of East Sikkim (India) and Bhutan. This article, thus, adds to the global knowledge of the subspecies with a note on its habitat and activity pattern, along with new details on it’s current global distribution.

    Keywords: Callosciurinae, ecology, habitat, native species, new report, rodent
  • Debayan Gayen*, Biswajit Mukherjee, Sanchari Sarkar, Bappa Goswami, Sagar Adhurya, Moitreyee Chakrabarty Pages 58-73

    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.

    Keywords: Bakreswar Reservoir, Birbhum, migratory birds, point count, waterbirds
  • Ayan Mondal, Nilanjan Das, Sudipto Mandal* Pages 74-90

    The domestication of rice (Oryza sativa L.) has a rich history with its diversification from wild progenitors based on genetic differences. For human benefit, natural environments have been agriculturally modified. Concurrently, the biodiversity of natural or wild environments is greatly affected. Here, a comparison has been made between the biodiversity associated with wild-type rice and domesticated rice fields. Species were categorized into broad groups, i.e. Arthropoda (Arth), Other Invertebrate (OInv), Vertebrate (Vert), Algae (Alg), Fungi (Fng), Pteridophyta (Ptrd), and Higher Plant (HPlan). Physico-chemical factors including water depth (WD), water pH (pH), temperature (T), total hardness (TH), dissolved organic carbon (DOC), turbidity (Turb), and dissolved oxygen (DO) were measured directly in the field. Statistical analysis such as Student’s t-test, Kolmogorov-Smirnov test for equal distributions, tests for dominance and multiple indices including Simpson, Shannon, and Evenness were used to assess the biodiversity. Furthermore, Principal Component Analysis (PCA) and Multivariate Analysis of Variance (MANOVA) were used for community comparisons, and SIMPER analysis was used to assess dissimilarity between taxa. The Artificial Neural Network model (ANN) was applied to assess the relative importance of factors governing the system. The present study showed the assemblage of species in the wild along with domestication. The vertebrate species number was well correlated with all the other biotic groups indicating a bottom-up controlling pattern in the rice field ecosystem. The ANN analysis showed that of the environmental factors examined, WD played the most important role followed by pH, T, DOC, and DO as the next most influential factors in distinguishing wild and domesticated rice field ecosystems. SIMPER analysis demonstrated that arthropods were a major contributor to dissimilarity. Collectively our results showed that the domestication of rice led to a decline in biodiversity.

    Keywords: Diversity, crop, Oryza sativa, Oryza rufipogon, physico-chemical variables