Zoology

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Assessment of Organophosphate toxicity in economically important fish species of Nepal
(Institute of Science and Technology, Zoology, 2022) Kunwar, Prabesh Singh
Available wih full tex
BIO-MEDICAL AND GENETIC ANALYSIS OF BETA THALASSEMIA IN THE ETHNIC GROUPS OF EASTERN NEPAL
(2023-05-31) SHRESTHA, GITA
Hemoglobinopathies and thalassemias are the most common monogenetic disorders in Southeast Asia. These are the only genetic disease where carriers can be detected using hematological findings rather than genetic analysis. The detection of Beta-thalassemia relies on estimation of red blood cell parameters that reveal microcytic hypochromic anemia. Carriers of this disorder are usually asymptomatic and non-transfusion dependent. However, marriage between two carriers produces severe transfusion dependent Thalassemia major off-springs who seldom survive beyond two years of age. The affected families suffer psychological, emotional, social and economical stress. In Nepal, this disorder is common in the malaria endemic regions of the Terai. Therefore, this study was aimed to assess the status of hemoglobinopathies and thalassemias in some ethnic groups of the Terai region in Eastern Nepal. This descriptive cross-sectional study was done from 06/01/74 to 29/12/77. Total 1500 individuals were enrolled for screening. The blood samples and demography were collected randomly from asymptomatic individuals belonging to the Koch Rajbanshi, KochilaTharu, Musahar, Musalman and Santhal ethnic groups of Jhapa, Morang and Sunsari districts. Haematological parameters were derived from automated coulter counter, peripheral blood smear was examined microscopically, hemoglobin electrophoresis was done by Capillary electrophoresis (Sebiaminicap flex piercing) and genotyped with multiplex amplification refractory mutation system-polymerase chain reaction for nine mutations. Out of the total 1500, 285 (19%) cases suffered from microcytic hypochromia anemia. Abnormal haemoglobinopathies was detected in 184 (12%) cases. In which β thalassemia trait was (44.44%), followed by HbE trait (34.56%) and HbE Homozygous (20.98%) in overall population. In the Koch Rajbanshi ethnic group Hemoglobin E variant was the only abnormal hemoglobinopathy found. Whereas inthe Santhals only Beta-thalassemia heterozygous was detected. The mutationsidentified were C-15 (G→A), IVSI-5 (G→C), FS 8/9(-TCCT) and C-26 glu-ly. The results of this study revealed that the ethnic groups of eastern Nepal are a rich reservoir for thalassemia and hemoglobinopathies. A regional and ethnic specificity in the mutational profile among the studied population was evident.
ECOLOGY AND FEEDING BEHAVIOR OF ASSAMESE MONKEYS (Macaca assamensis) in MID-HILLS OF NEPAL
(2023-05-31) GHIMIRE, SUVAS CHANDRA
A study on Assamese monkeys (Macaca assamensis) was performed in the Kaligandaki river basin (KRB) of western Nepal and in the Budhigandaki river basin (BRB) of central Nepal. The field study was conducted from February 2015 to January 2016 spending 1804 hours to explore the ecology and feeding behavior of Assamese monkeys. During the study period, a total of 42 individuals of Assamese monkeys with two troops (Palpa troop n=24 and Syangja troop n=18) with mean group size 21 in KRB and that of 43 individuals with three troops (Rigdikhola troop n=16, Rockybhir troop n=13 and Siurenitar troop n=14) with mean group size 14.33 in BRB were recorded. Pearson’s Chi-squared test (χ2 = 20.5511, p = 0.665) and Fisher’s exact test (p = 0.861) show that there is no significant difference in distribution pattern of Assamese monkeys among blocks (Block A, Block B, Block C, Block D and Block E). Two troops of Assamese monkeys, one from KRB named as Kaligandaki focal Assamese Syangja troop (KFAST) and other from BRB named as Budhigandaki focal Assamese Siurenitar troop (BFAST) were monitored using scan sampling and focal animal sampling methods to understand the ecology and feeding behavior of the monkeys in two different topographical river system of Nepal. Botanical quadrate sampling (20 m  20 m) plotted in different altitudinal areas of KRB forest revealed that Trichilia connaroides was the dominant plant species with relative density 35.68% and relative frequency 8.38% while Shorea robusta was the dominant plant species with relative density 29.75% and relative frequency 8.87% in BRB forest. Different quadrate plots and vegetation analysis revealed that the Assamese monkeys of KRB and BRB were found inhabited in sub-tropical deciduous riverine forest with rocky cliffs habitat. Kaligandaki Assamese monkeys frequently used leaf of Albizzia chinensis and that of Budhigandaki used leaf of Lagerstroemia parviflora as major food throughout the year. Most of the botanical quadrate plots also included Albizzia chinensis species in Kaligandaki area and that of Lagerstroemia parviflora species in Budhigandaki area although dominated by Trichilia connaroides in Kaligandaki and Shorea robusta in Budhigandaki. Further, the sleeping sites of the Assamese monkeys during night time were found on rocky cliffs and rocky outcrops of both the river basin rocks. These rocky cliffs and rocky outcrops were very close with specific food plants of the monkeys in both the sites that might help them to prefer this type of habitat. Four major behaviors namely feeding, resting, moving and grooming were recorded. During 716 hours of observation period in Kaligandaki, the total feeding time spent by Assamese monkeys was 294.7 hours (41.16%) and in Budhigandaki during 691 hours observation period, the total feeding time spent by the monkeys was 306.5 hours (44.36%), as highest in both sites followed by resting, moving and grooming. Special emphasis was given to time investment and food intake by the monkeys. They preferred fruits (27.19% in Kaligandaki and 29.54% in Budhigandaki) as the highest intake per year in gram percentage followed by mature leaf and others, however the feeding time spent per year was higher on mature leaf (30.02% in Kaligandaki and 29.04% in Budhigandaki) followed by fruits and others. This shows from the results that food intake amount and time investment on feeding of different plant parts may differ depending on the nutritive value of food availability. Data from systematic behavioral observations were analyzed with reference to that of the vegetation surveys. Assamese macaques invested more than two-fifths (>40%) of the diurnal time on feeding. The two study troops inhabiting highly similar habitats of food plants (Sorensen’s Similarity Index = 0.93) didn’t have a significant difference in the selection of food-plant parts. This concludes that food choice and time investment on the feeding of different plant parts differ depending on the availability of food in the area. Macaques living in comparable habitats with similar food plants have analogous food choices and time investments. Crop raiding by Assamese monkeys is one of the serious problems in both KRB and BRB villages. Maize crop was highly preferred (47.14% in Kaligandaki and 58.43% in Budhigandaki) by the Assamese monkeys as a major crop raid followed by others. Monkeys raid the crops mainly due to the scarcity of natural foods and degradation of their habitats. Therefore, conservation attempts should be focused on this nationally endangered and protected primate species in Nepal in order to provide a practical guide to future conservation.
Effects of Water Hyacinth Invasion to Aquatic Biodiversity of Lakes in Pokhara Valleyo Nepal
(Institute of Science & Technology, 2023-06) Basaula, Rajendra
Proliferation of non-native invasive species poses a serious hazard on ecosystem structure and functioning, leading to decline in native species, habitat alteration, and nutrient cycling. Water hyacinth (Pontederia crassipes) is native in Brazil and now it is spreading globally in tropical and subtropical regions with detrimental impact in aquatic ecosystem. Despite the presence of water hyacinth in the Pokhara valley lakes for over two decades, its impact on water quality and aquatic biodiversity in the lakes of Pokhara Valley remains largely unexplored. To minimize the gap, the current study explored the effect of invasion of water hyacinth on physicochemical parameters, and abundance and diversity of macro-invertebrates, fishes and waterbirds in the lakes of Pokhara. The lakes were categorized into water hyacinth presence and absence habitat on the basis of occurrence of water hyacinth. Water hyacinth was present in Phewa, Begnas and Rupa throughout the study period, however, all area was not occupied by it. Therefore, each lake was categorized in water hyacinth presence and absence habitat, and the small lakes are without water hyacinth and are kept under water hyacinth absence habitat. The seasonal data on water quality, macro-invertebrates, fish and waterbird species were collected from 24 sampling plots from 2019 to 2020. The water sample, macro-invertebrates and fish were collected from each plot of 50 × 50 m2 using plastic bottles, Peterson’s Grab Sampler and gill net enclosures, respectively. Waterbirds data were collected from 50 m radius of each plot by direct observation. Water quality was found to be degraded in areas with water hyacinth. Free carbon dioxide and water temperature had the significant and positive association with water hyacinth coverage but opposite for same was recorded for other parameters including depth, transparency, pH, dissolved oxygen, total alkalinity and nitrate. Water hyacinth invasion has had the detrimental impact on the abundance and diversity some macro-invertebrates, fish and waterbirds in the lakes of Pokhara Valley. During the study period, 29 macro-invertebrate’s species were collected including 26 genera from 21 families and 15 orders, with orders Diptera and Haplotaxida being less abundant in areas infestation with water hyacinth. The study also documented overall 20 species of fishes including 18 genera, eight families and six orders with Cyprinidae the most abundant family. The exotic species Nile tilapia (Oreochromis niloticus) was found to be the most abundant fish in both areas, with higher abundance in areas with water hyacinth (p < 0.001). Exotic fish species were positively correlated with water hyacinth coverage (R = 0.066; p < 0.001). A total of 32 waterbird species of 11 families were recorded in the lakes of Pokhara Valley. The study found the water hyacinth infested area had lower threatened waterbird abundance compared to areas without it (p = 0.023). The abundance and species richness of threatened waterbird declined in water hyacinth presence habitat during this study period but these were positively correlated with depth of and overall bird abundance. The current study provided the baseline data of invasion of water hyacinth and its effect on the physicochemical parameters and aquatic fauna of the lakes. Therefore, the lake managers and policymakers can use these data to develop policies for removing or managing water hyacinth in the lakes of Pokhara Valley to improve aquatic biodiversity conservation. आयातित मिचाहा प्रजातिहरूको फैलावटले पारिस्थितिक प्रणालीको संरचना र कार्यप्रणालीमा गम्भीर खतरा निम्त्याउँछ, जसले स्थानीय प्रजातिहरूमा गिरावट, बासस्थान परिवर्तन र पोषक तत्व चक्र संचालनमा असर गर्दछ । जलकुम्भी (Pontederia crassipes) ब्राजिलको स्थानीय विरूवा हो र अहिले यो संसारभरका उष्ण र उपोष्ण क्षेत्रका सबै जसो मुलुकहरूमा मिचाहा प्रजातिको रूपमा फैलिरहेको छ र जलीय पारिस्थितिक प्रणालीमा नराम्रो असर पारिरहेको छ । पोखरा उपत्यकाका तालहरूमा दुई दशकभन्दा अगाडिदेखि जलकुम्भी भित्रिएको भए तापनि यसले तालको पानीको गुणस्तर र जलीय जैविक विविधतामा पारिरहेको प्रभावका बारेमा धेरै हदसम्म अस्पष्ट छ । यो अस्पष्टतालाई न्यूनीकरण गर्न, हालको अध्ययनले पानीको भौतिक तथा रासायनिक गुणहरू, आँखाले देख्न सकिने ढाडमा हाड नभएका जलीय जीवहरु, माछाहरू र जलपक्षीहरूको उपस्थिति र विविधतामा जलकुम्भीले पार्ने असरहरूका बारेमा अन्वेषण गरेको छ । यो अध्ययनको लागि सर्वप्रथम तालहरूलाई जलकुम्भी पाइने र नपाइने ठाउँको आधारमा वर्गीकरण गरियो । फेवाताल, वेगनासताल र रूपातालमा जलकुम्भी भएका र नभएका दुवै खालका अध्ययन क्षेत्रहरू निर्धारण गरियो भने साना तालहरूमा जलकुम्भी नभएको हुनाले प्रत्येक तालमा जलकुम्भी नभएको एउटा मात्र अध्ययन क्षेत्र निर्धारण गरिएको थियो । यसरी सन् २०१९ देखि २०२० सम्ममा जम्मा ५० मिटर × ५० मिटरका २४ वटा अध्ययन क्षेत्रहरूबाट पानी, ढाडमा हाड नभएका जीवहरू, र माछाहरूको मौसमी नमुनाहरू सङ्कलन गरिएको थियो । पानी, ढाडमा हाड नभएका जीवहरू र माछाहरूको नमुना सङ्कलन गर्न क्रमश प्लाष्टिकका बोतलहरू, पेटरसन ग्रयाब स्याम्पलर (Peterson’s Grab Sampler) र गिल नेट प्रयोग गरियो । जलपक्षीहरूको नमुना भने प्रत्येक अध्ययन क्षेत्रमा ५० मिटर अर्धब्यासभित्र प्रत्यक्ष अवलोकन विधिद्वारा गरिएको थियो । जलकुम्भीको कारणले गर्दा तालको पानीको गुणस्तर खस्किएको पाइएको छ । जलकुम्भीले ओगटेको प्रतिशतसँग कार्वन डाइअक्साइड र पानीको तापक्रमको अत्यन्तै सकरात्मक सम्बन्ध रहेको पाइयो तर पानीको गहिराइ, पारदर्शिता, घुलनशील अक्सिजन, कुल क्षारीयता र नाइट्रेट लगायतका अन्य मापदण्डहरूमा यसको नकरात्मक असर पाइयो । पोखरा उपत्यकाका तालहरूमा मिचाह जलकुम्भीको फैलावटले गर्दा ढाडमा हाड नभएका जीवहरु, माछा र जलपक्षीहरूको उपलब्धता तथा विविधतामा नकरात्मक प्रभाव पारेको भेटियो । अध्ययन अवधिभरमा ढाडमा हाड नभएका जीवहरुका २१ परिवारहरू (Families) र १५ अर्डरहरूबाट जम्मा २६ जातिसहित २९ प्रजातिहरू सङ्कलन गरिएको थियो । अर्डरहरू डिप्टेरा (Diptera) र ह्याप्लोटाक्सिडा (Haplotaxida) समुहका जीवहरूको उपस्थिति जलकुम्भी भएको क्षेत्रमा धेरै कम पाइयो । त्यसैगरी माछाका आठ परिवारहरू (Families) र छ अर्डरहरूबाट १८ जातिसहित २० प्रजातिहरू अभिलेख गरिएको छ, जसमा साइप्रिनिडे (Cyprinidae) सबैभन्दा प्रचुर मात्रामा पाइएको परिवार रह्यो । जलकुम्भी भएको र नभएको दुबै ठाउँहरूमा मिचाहf प्रजातिको माछा नाइल तिलापिया (Oreochromis niloticus) प्रचुर मात्रामा पाइएको थियो तर पनि तुलनात्मकरूपमा जलकुम्भी भएको क्षेत्रमा यसको उपस्थिति बढी थियो (p = ०.००१) । मिचाहा प्रजातिका माछाहरू र जलकुम्भीले ओगटेको क्षेत्रफल बिच असाध्यै सकारात्मक सम्बन्ध भएको पाइयो (p = ०.००१) । यो अध्ययन अवधिमा पोखरा उपत्यकाका तालहरूमा ११ परिवार (Families) भित्र ३२ प्रजातिका जलपक्षीहरू पाइएका थिए । जलकुम्भी नभएको क्षेत्रको तुलनामा जलकुम्भी भएको क्षेत्रमा धेरै रैथाने जलपक्षीहरू पाइएको थियो (p = ०.०२३) । संसारभरि नै खतरामा परेका जलपक्षीहरूको प्रचुरता र यिनीहरूको प्रजाति सङ्ख्या जलकुम्भी भएको बासस्थानमा अति नै कम पाइयो तर यी पक्षीहरूको सम्बन्ध पानीको गहिराइ र समग्र पक्षी उपलब्धतासँग सकारात्मक रहेको भेटियो । यस अध्ययनले तालको पानीको भौतिक तथा रासायनिक गुणहरूमा र जलीय जीवहरूमा जलकुम्भीको प्रभावका बारेमा आधारभूत तथ्याङ्क प्रदान गरेको छ । तसर्थ पोखरा उपत्यकाका तालहरूको जलीय जैविक विविधता संरक्षणमा सुधार गर्न, तालबाट जलकुम्भी हटाउन वा व्यवस्थापन गर्न र नीति निर्माण गर्न ताल व्यवस्थापकहरू र नीति निर्माताहरूको निमित्त यी तथ्याङ्कहरू उपलब्धिमूलक हुनेछन्, जसले गर्दा त्यहाँ रहेका जीवजन्तुहरूको संरक्षण गर्न मद्दत गर्ने छ ।
Environmental Impacts, Systematics and Distribution of Herpetofauna from East Nepal
(Doctor of Philosophy in Zoology, 2003) Rai, Kalu Ram
In this thesis, various environmental impacts on the ecological zones of the East Development Region of Nepal have been covered. The studied area includes lakes, ponds, watershed areas, springs, streams and rivers, wetland habitats. Forests, forest bottom leaf litters, buffer zones, community forests, cultivated lands, abandoned and arid zones were investigated as terrestrial habitats. Location and directions of mountain ranges from Siwalik to Midland and Highland landscapes were also recorded. The monthly and annual records of temperature, humidity, light and precipitation records from each climatic station of all districts have been analyzed to assess important abiotic factors in the studied area. Impacts occurring from land-use pattern, socio-development and population growth are also discussed, with evidences of observation from this research area. Furthermore, deforestation and industrialization in the process of progressive development are one of the causes for slowly but steadily increasing pollution. The main focus on the herpetofauna of East Nepal has been the distribution situation and the human impacts, respectively. The turtle situation in East Nepal was another important problem object made during the research period. Systematic study down to species level of amphibians (Gymnophiona, Caudata, Anura) and reptiles (Chelonia, Sauria, Serpentes and Crocodylia) was made. In ethnologic aspect, the tribalzoological names were collected from the lowland, Midland and highland ethnic groups. Besides this, herpeto-batracho-coenosis is another very important aspect used to
Fecundity and Gonadal Development of Copper Mahseer, Neolissochilus Hexagonolepis (McClelland, 1839) from Tamor river, Nepal
(Institute of Science and Technology, 2019) Subba, Suren
The present work was intended to assess the fecundity and gonadal development of Neolissochilus hexagonolepis from Tamor River, Nepal. The study was conducted for the duration of two years, from December 2014 to November 2016. Monthly samples of N. hexagonolepis were procured from the river. Altogether one hundred ninety eight samples were examined. The length-weight relationship (LWR) was found to be following the model of Le Cren (1951). The value of the regression coefficient (b) for all the LWR was close to 3, which indicated that the fish showed an isometric growth pattern. The general well being of the fish from the river was found to be satisfactory. The assessment of fecundity unveiled N. hexagonolepis as a low fecund fish. The number of eggs in the ovaries of N. hexagonolepis increased proportionately with increasing length, body weight and gonad weight of the fish. The enumeration of gonado-somatic index (GSI) showed the species as an annual breeder with peak spawning activity from July to August. The egg size estimation revealed the species as a multiple spawner. Male individuals dominated the smaller size classes and female individuals dominated the larger size classes. The testes and ovaries were observed at six stages of maturation viz. Immature, maturing virgin, ripening, mature, spawning and spent. The developing oocytes within the ovigerous lamellae of the ovaries were observed at the chromatin-nucleolus stage, early and late peri-nucleolus stages, early and late yolk vesicle stages and early and late yolk stages. The species showed an extended breeding period from May to November. Male and female individuals attained the first sexual maturity at size 25.5 cm and 32.9 cm, respectively. Environmental variables played an essential role in governing the reproductive biology of the fish. Temperature contributed positively to the development of the fish’s gonads during its breeding season.
Landscape correlates of large mammal occupancy in Chitwan Annapurna Landscape, Nepal
(Institute of Science and Technology, Zoology, 2022) Adhikari, Jagan Nath
Human activities and natural processes are causing landscape change and biodiversity loss. Large mammals are among the most threatened animals by land use and land cover change (LULCC). They are under the pressure of habitat loss and alternation, especially in the areas outside the protected area system. Chitwan Annapurna Landscape (CHAL) is a north-south linkage between Chitwan National Park and Annapurna Conservation Area in central Nepal that provide a safe passage of forest corridor for wildlife. This study attempted to: 1) characterize the spatio-temporal pattern of land use and land cover change in central part of CHAL; 2) evaluate the relative abundance of large mammals and their interaction with people; 3) examine the impacts of environmental correlates on the occupancy of large mammals, and 4) identify the landscape level connectivity for the large mammals. The LULCC in the area was characterized by supervised classification of Landsat images for 2000, 2010 and 2020. Relative abundance of large mammals in four different blocks (A–D) of the study area was done by line-transect (n = 150, average length = 3.18 ± 0.11 km) survey. Interaction of human with large mammals were assessed through the questionnaire survey among 600 respondents. The occupancy of the large mammals was evaluated using the program PRESENCE. Potential distribution of the large mammals and their environmental correlates were identified by species distribution modelling using maximum entropy algorithm. Important landscape patches in the study area were identified and least-cost path approach with circuit theory was used to pinpoint the linkages among those patches. The Kernel density estimation method was used to identify the hotspots for the connection of isolated population of the mammals in the patches. The LULCC results revealed that forest is dominant feature of the study area. Overall forest increased by 360.52 km 2 and cropland, grassland and barren area decreased by 329.45 km 2 , 46.78 km 2 and 12.18 km ix 2 respectively from 2000 to 2020. A total of 18 species of large mammals were enumerated from primary field data. Chital was the most abundant species in lowland (block A) and northern red muntjac in mid-hills (blocks B, C and D). Among the carnivores, tiger was recorded only from the lowlands while leopards were reported throughout the landscape, and Himalayan black bear was reported in blocks B, C and D. Land cover types, anthropogenic disturbances, and coverage of invasive and alien plant species (IAPS) have been identified to affect the abundance of large mammals. The human-large mammal conflict is a serious problem in this landscape with an estimated annual loss of US$ 12.02 and 74.60 per household from crop damage and livestock depredation, respectively. The highest estimated occupancy (ψ = 0.944 ± 0.048) was found for leopard whereas the lowest occupancy was for Himalayan goral (ψ = 0.038 ± 0.011). Species distribution model predicted 30.29% of the study area as suitable habitats for northern red muntjac, 6.45% for chital, 2.6% for sambar, 14.55% for wild pig, 15.55% for Himalayan goral, 34.88% for rhesus macaque, 34.65% for langur, 5.79% for Himalayan black bear and 29.94% for leopard. A total of 15 habitat patches were identified in the central part of CHAL on the basis of suitable habitats of mammals. The study found a poor connectivity among the patches for chital and sambar, a strong connectivity for muntjac, leopard, rhesus macaque and langur in the lowland to mid-hill and a strong connectivity for Himalayan black bear and Himalayan goral in mid-hills. The heterogeneity and dynamics in the landscape pattern in CHAL mainly attributed forest change due to migration of people from rural to urban and lowland areas. Landscape conservation efforts in the CHAL should maintain the contiguity of forest patches. This research provides the baseline information of large mammals in the CHAL and how they are responding to changes in the landscape. It reveals the role of fragmented landscape for supporting large mammal assemblages and conserving biodiversity.
"Microhabitat Assessment and Community Conservation Awareness for Cheer Pheasant in Myagdi District, Nepal"
(2024-06) Chokhal, keshab; Dr. Bishnu Prasad Bhattrai
The Cheer Pheasant is endemic species to the foothills of the Western Himalayas. In January 2024, a survey was carried out across forty-three sites in the Myagdi district to study its microhabitat preferences and start a conservation awareness campaign. Data collection utilized direct observation methods, while the awareness program featured slide presentations. The survey findings revealed affirmative regression between the presence of Cheer Pheasants and the plentiful availability of herbs (0.019*, P<0.05), ground cover (0.051., P<0.05), and gravel (0.064., P<0.05). Conversely, it was negatively impacted by the number of trees (-0.164, P>0.05). Camera traps have employed to detect Cheer presence; although species was not captured, other wildlife species were successfully recorded. Habitat disturbance was primarily caused by fire (68%) and road construction (20%), with poaching/snaring (6%) playing a minor role but increasing steadily across study sites. A community conservation awareness program was conducted at Jyoti Primary School, Sida Santi Secondary School, and Dipshika Secondary School, involving a total of 70 participants. Drawing competitions were held among intra-class and inter- class students to promote Cheer Pheasant conservation in the study areas. The collaboration between the head teacher and the school management committee facilitated the distribution of prizes for the winners of the drawing competition. Continuous conservation monitoring and raising awareness among local communities are crucial for the conservation of Cheer Pheasants in the Myagdi district.
Population structure, breeding success, and behavior of white-rumped vulture Gyps bengalensis in the Gandaki River Basin, Nepal
(Institute of Science & Technology, T.U., 2024-04) Gautam, RamjI; Dr. Hari Prasad Sharma
Once abundant, the white-rumped vulture (Gyps bengalensis), suffered a catastrophic population decline due to the veterinary use of diclofenac. South Asian countries, including Nepal banned veterinary diclofenac production, distribution, and use in 2006. However, little is known about the population trends on critically endangered white-rumped vulture within the Gandaki River Basin of Nepal. This study investigated the population trends of white-rumped vultures in the Gandaki River Basin through direct observations in the field from 2006 to 2022. This involved total count surveys to record a population size, and the number of occupied nests and productive nests. In addition, the white-rumped vulture behavioral sequences were also assessed during the breeding season using Monte Carlo simulations. This study also explored white-rumped vulture’s tree species preferences for nest building and the factors influencing it. This study found the white-rumped vulture population continuously declining over the past 16 years, despite the veterinary diclofenac ban. The minimum and maximum number of vultures were 54 and 114, respectively. Among the recorded individuals the highest average adult population was 90.23%, and followed by sub-adults, and juveniles. The intrinsic population growth rate was declining (mean-count: β = 0.01, t = 1.04, p = 0.32; maximum-count: β = 0.01, t = 1.04, p = 0.32) during the study period. The population growth was determined by the number of productive nests, which increased 3.7% in the study area. Twenty-four percentage (n = 205) occupied nests remained eggless during the egg laying period, 16.84% (n = 144) nests failed during incubation period, and 11.23% (n = 96) in fledgling period. The breeding success i.e., fledging of chicks from the nest was influenced by precipitation, and average maximum and minimum temperature. The behavioral sequence of white-rumped vulture indicated that they spent > 70% time in breeding activities and exhibited predatory behavior. The white-rumped vultures built nests on 18 tree species in the study area. The kapok/silk cotton tree (Bombax ceiba) was the preferred one for nest construction (χ2 = 115.38, df = 1, p < 0.001) among the available tree species. The nest construction of white-rumped vultures was influenced by specific tree characteristics, such as the number of whorls, canopy spread, and tree height. Unfortunately, human activities in infrastructure development and commercial logging of the nesting trees decreased the availability of large and matured trees in nesting sites for the white-rumped vultures. This study found that the major cause of the decrease in the nesting colony was the destruction of its nesting trees. This study indicates that veterinary diclofenac is not only the major determining factors for white-rumped vulture population decline. Other factors, such as low breeding success, potential disruptions in behavioral patterns, and critical nesting habitat loss posed additional threats to the white-rumped vulture population in the Gandaki River Basin. Based on these findings, this study recommends prioritizing the conservation of kapok trees, a preferred nesting habitat for white-rumped vultures. These baseline data can be used for developing site-specific conservation strategies to increase vulture population sizes. दक्षिण एसियामा व्यापक रूपमा फैलिएका डंगर गिद्ध (Gyps bengalensis) को संख्या तिव्र रूपमा घट्नुमा पशु उपचारमा प्रयोग हुने डेक्लोफेनेक औषधीको असर थियो । वि.सं. २०६३ (सन् २००६) मा यस औषधीको उत्पादन र प्रयोगमा छिमेकी देशसहित नेपालले प्रतिबन्ध लगायो । यस अध्ययनले प्रतिबन्ध पछिको अति संकटपूर्ण रूपमा रहेको डंगर गिद्धको दीर्घकालीन संख्याको अनुगमन, प्रजनन सफलता र पर्यावरणीय अवलोकनका बारेमा गण्डकी जलाधारमा अनुसन्धान गर्ने लक्ष्य राखेको थियो । वि.सं. २०६३ देखि २०७९ सम्म (सन् २००६ देखि २०२२) गण्डकी जलाधार क्षेत्रमा डंगर गिद्धको दीर्घकालीन संख्याको अनुगमन, प्रजनन सफलता र पर्यावरणीय अवलोकनका साथै गिद्धको व्यवहारमा गणितीय प्रयोग पनि गरियो । डंगर गिद्धले गुँड लगाउने रुखको पहिचान गरी गुँड लगाउने रुखका विशेषताहरूको बारेमा पनि अनुसन्धान गरिेएको छ । बिंगत १६ वर्षको अध्ययन अवधिभर डंगर गिद्धको संख्यामा गिरावट रहेको देखियो । डंगर गिद्धको औसत निम्नतम संख्या ५४ र अधिकतम संख्या ११४ रहेको पनि पाइयो । जसमध्ये उच्चतम ९०.२३% वयस्क र क्रमैसँग अल्प–वयस्क र किशोर रहेका छन् । डंगर गिद्धको संख्याको प्रतिगमन वृद्धिदर (औसत गणना विधि ( =०. ०१, t = १.०४, p = ०.३२ र अधिकतम गणना विधि ( = ०. ०१, t = १.०४, p = ०.३२) स्थिर रहको देखियो । प्रजनन सफल गुँडको ३.७% वृद्धिले डंगर गिद्धको संख्यामा असर पा¥यो । डंगर गिद्धका २४% (n = २०५) गुँड बनाउँदा, १६.८४% (n = १४४) ओथारो बस्दा र ११.२३% (n = ९६) बच्चा उडाउने बेलामा प्रजनन असफल रह्यो । डंगर गिद्धको प्रजननलाई वार्षिक वर्षा र औषत न्यूनितम तापक्रमले असर पा¥यो । प्रजननको समयमा डंगर गिद्धले धेरै समय (> ७०%) सन्तानको रेखदेखमा व्यथित गरेको पाइयो । डंगर गिद्धले जम्मा १८ प्रजातिका रुखमा गुँड बनाए पनि सिमलको रुखलाई अधिकतम प्रयोग गरेको भेटियो । यसरी गुँड बनाउँदा जमिनबाट पहिलो अग्लो हाँगा र धेरै हाँगाहरू भएको रुखहरूलाई रोजेको पाइयो । अव्यवस्थित भौतिक संरचना र रुख कटानहरूले गर्दा डंगर गिद्धले आफ्नो गुड लगाउने स्थानहरूलाई असर गरेको भेटियो । जसले गर्दा डाइक्लोफेनेक प्रतिबन्ध पछि संख्या घट्नुमा प्रजननमा अवरोध, गुँड बनाउने रुखहरूको क्षति हु्नु पनि यो गिद्धको संख्या घट्नुको प्रमुख कारण हो । डंगर गिद्धले गुँड बनाउने सिमलका ठुला रुखहरुको संरक्षण र विषाधिमुक्त सिनोको प्रयोगले यस गिद्धको लामो समयसम्म बाच्ने आधार खडा गर्ने छ । यस्ता दीर्घकालीन अध्ययनले डंगर गिद्धको प्रजाति र स्थान विशेष संरक्षण रणनीतिहरुको आधार स्थापित गर्ने छ भन्ने कुरालाई सारको रूपमा प्रस्तुत गरिएको छ ।
Prevalence of Gastrointestinal parasites in rhesus macaques (Macaca mulatta, Zimmermann 1780) and Human community in Bijaypur, Dharan, Nepal
(Institute of Science & Technology, 2024) K.C, Manisha; Dr. Laxman Khanal
Rhesus macaques (Macaca mulatta) are distributed across Nepal in close association with humans and with a high probability of sharing of gastrointestinal parasites. This study aimed to evaluate the occurrence, diversity, and determinants associated with gastrointestinal parasites in rhesus macaques and the people residing in the Bijaypur area of Dharan, Sunsari, Nepal. Microscopic methods, including direct wet mount, floatation, and sedimentation, were used to analyze fecal samples from 50 macaques and 50 humans. The results revealed that among the rhesus macaques, the general prevalence of gastrointestinal parasites was 62%. The most prevalent parasites were Trichuris sp. (52%), followed by Entamoeba sp. (22%), Ascaris sp. and Hookworm (12% each), Eimeria sp. (6%), and Strongyloides sp. (2%). In contrast, humans exhibited a lower parasitic infection rate of 6%, with Entamoeba sp. being the most common (6%), followed by Hookworm (4%) and Trichuris sp. (2%). The Sorenson’s Coefficient of Similarity for the assessment of similarity in GI parasites between rhesus and humans, was found to be 0.67, indicating a moderate level of similarity. The mean parasite richness in infected macaque samples was calculated to be 1.70± 0.64 (SD), highlighting the diversity of parasites present in these primates. The study suggests that the substantial occurrence of GI parasites in rhesus macaques can be linked to their close association with humans, sharing habitats and food sources. This situation increases the potential for the bi- directional flow of parasites between the two species and raises concerns about zoonotic transmission, emphasizing the importance of routine monitoring and effective management strategies to mitigate the risks associated with such interactions.
Seismic Hazard analysis of Nepal
(Institute of Science and Technology, Zoology, 2019) Rajaure, Sudhir
Nepal is situated in the central part of the Himalaya, which is one of the most seismically active zones in the world. Nepal has witnessed several mega-quakes, with magnitude above 8, and thousands of smaller earthquakes. The 2015 Mw 7.8 Gorkha earthquake is the most recent significant event in the country. Large and moderately large earthquakes can have a tragic impact on people and society as a whole. The preparation of seismic hazard map and evaluation of site specific ground motion due to earthquake are recognized as the fundamental steps towards the earthquake risk reduction. An attempt is made to develop seismic hazard maps of Nepal using available data of earthquakes, recent knowledge of seismotectonics and refined geological features. A comprehensive and magnitude-homogenized earthquake catalogue is prepared from the processing of earthquake catalogues collected from different sources. Thus prepared catalogue contains earthquake data since 1100 AD to 2017 AD. Nine sets of potential earthquake source models are delineated after the analysis of the seismicity distribution, geological structures, results of different geophysical and geodetic surveys and the experience of 2015 Gorkha Earthquake. Probabilistic technique of seismic hazard analysis is applied to evaluate seismic hazard in Nepal. The result shows high hazard in an east-west elongated belt that runs parallel to the front of the Higher Himalaya. The maximum PGA reaches about0.45 g in farwest Nepal and about 0.4 g in Kathmandu Valley for 10 % probability of exceedance in 50 years, at engineering rock site. The effect of the sediments of the Kathmandu sedimentary basin is investigated using strong motion data of earthquakes recorded in the Kathmandu Valley. During the Mw 7.8 (Gorkha) earthquake, the largest PGA (0.25 g) was recorded at Kirtipur (KTP), which is a rock site. The record shows a single and unusual spike, which is attributed to the permanent displacement of the Main Himalayan Thrust. The second largest PGA (0.23 g) was recorded at the Central Department of Geology (Tribhuvan University (TVU)), which is a soil site. During the Mw 7.8 earthquake, the PGAs were vii comparatively smaller at all soil sites, whereas the peak ground velocity (PGV) was small at KTP (rock site) and were larger at all other soil sites. The strong motion records of the earthquakes depict the predominant period being between 3 and 5 seconds at the soil sites. The high frequencies (>2.5 Hz), were strongly damped and the low frequencies (<2.5 Hz) were amplified at the soil sites, therefore tall buildings suffered more and the low rise buildings suffered less when compared. The amplification factor was small during the stronger earthquakes and was large during smaller earthquakes; thus demonstrating non-linear response of soil. The analysis shows that the azimuthal effect of earthquake sources was not observed in the Kathmandu Valley. Earlier reports on the 1934 Bihar-Nepal Earthquake (Mw 8.2) and 1833 North Kathmandu Earthquake (Mw ~7.6) report localized massive destruction in the Kathmandu valley and attribute the massive destruction to local geology of the basin (Pandey and Molnar, 1988). Contrary to these claims, amplification of ground acceleration was not observed in the Kathmandu valley during the 2015 Gorkha Earthquake but the low frequencies were amplified. The seismic hazard map and ground response results are mandatorily considered in policy making, planning, formulation and revision of building codes, design of new infrastructures and retrofitting of existing infrastructures. It facilitates the seismic risk assessment, insurance policies and many other related matters.
Species Composition and Floral Association of Bumblebees (Bombus spp.) in Chitwan Annapurna Landscape, Nepal
(Institute of Science and Technology, T. U., 2024-06) Chandra Ghimire, Kishor Chandra; Dr. Daya Ram Bhusal
Bumblebees (Bombus spp.) are important pollinators especially in high altitude flowering plants either natural or cultivated types, yet these bee communities are rapidly declining globally. Understanding abundance, species composition, distribution patterns, foraging plant species and responses to environmental factors is highly needed to understand the long term conservation of these vital pollinators in Nepal. This research work was aimed to investigate the species composition of Bombus species and their foraging association with flowering plants present along the Chitwan Annapuna Landscape (CHAL). The field survey was carried out in the most flowering seasons of (April to November) of 2018 and 2019. Three walking accessible transects (600 to 3500 m asl.) along the Kaligandaki (Mustang site), Marshyandi (Manang site), and Budhigandaki (Gorkha site) river basins were followed for the collection of bumblebees. The transects passed through different types habitat such as agricultural, home gardens, grasslands, and forests. For the sample collection, researcher moved at a slow pace along the transect, 20 meters right and left. The entire walking process included three times up and three times down from April to November for two consecutive years. The total field collection was performed 108 days (April-May, July-August, October –November). Whenever a bumblebee was encountered, stopped at that point and spent 30 minutes for extensive searching around the point. All possible foraging workers of Bombus species were captured before continuing the walking along the transect. The specimens were collected by entomological sweeping net for hovering bumblebees and directly picked by hand-vials method for those bumblebee which are foraged inside the flower. For the plant-bumblebee network analysis, six plots (plot size: 40m x 40m) were established along the three transects (2 plots in each transect). The upper point was established at the 2800 m where flowering plants were highly clustered during the survey time. Similarly, lower point was also selected on this basis of availability of flowering plants. The lower point was established at 1700 m asl. All possible foraging workers that visited to the flowers were collected within 60 minutes. During the collection, the number of bumblebee visitation in each flower was noted. A single plot was observed for 12 times(hrs) during study period. If bumblebees were in contact with the reproductive structure of a particular flower, it was considered as valid individual for the visitation count. The bumblebees and flowering plant categories (e.g. native type, non-native cultivated type, non-native naturalized type, and invasive type) was analysed by using bipartite network analysis where upper level of network was represented by 16 Bombus spp. and lower level was represented by categories of plants. In this study, a total of 16 Bombus spp. were identified during the whole study period. The relative abundance of Bombus species vary with altitude, habitat, transect sites and foraging plant types. The relative abundance of B. haemorrhoidalis was highest (n= 134, 20.29%), followed by B. festivus (n=129, 19.57%) and B. eximius (n=124, 18.84%). But, species like B. branickii, B. miniatus, B. novus, and B. pressus were the least abundant species with 1% relative abundance of each. The effects of elevation on bumblebee richness was found significant (R= 0.2876 p=0.0007) and the highest richness was recorded at the mid-elevation (2000-3000 m asl.), likely attributed to the increased availability of pollinator-dependent flowering plants within this range. The highest species diversity was recorded in forest habitat of Gorkha site (Shannon index H′= 2.18), followed by grassland habitat of Mustang site (Shannon index H′= 2.10). In overall, species diversity was comparatively higher in the habitats of Gorkha transect site than Manang and Mustang sites. This indicates that the distribution, diversity, and species composition of bumblebees in CHAL primarily influenced by the habitat mosaic, elevation gradient and categories of host plants. The climatic variation that created alteration in vegetation dynamics among the three study river basins from eastern to western sites associated to the community composition and richness of Bombus species in CHAL. On other hand, drier sites in western rather than eastern sites of Himalayan landscapes probably associated with rich vegetation dynamics that alinked with the higher diversity in Gorkha site (Budhigandki basins) rather than western sites of this study. Overall result attributed to the higher mean precipitation in eastern parts of Nepal that followed by higher richness of flowering plants creating more opportunity for growing wider species of pollinator-friendly flowering plants in eastern sites of this study. Furthermore, the site specificity of some Bombus species would associated to the presence of specific flowering plant in that sites. This study examined the foraging relation of Bombus species by performing linear mix effective model, cluster analysis and corresponding analysis(CA) of plant families, flower colours and categories (invasive and non-invasive) of plants. This study that the plant families and colour of flower were important biotic factors for the forging choice of particular Bombus species in this landscape. There was a significant variation in the foraging intensity of identified bumblebee species with native versus non-native categories of plants and it is distinct with lower and upper elevation points. While in the plant-bumblebee interactions network analysis, the highest interaction was indicated in the native flora rather than invasive types of plant categories. This attributes the plant specific foraging behavior of certain bumblebee (specialist) species (eg: B. asiaticus, B. novus) where as some species are more generalist (e.g: B. festivus, B. tunicatus, B. haemorrhoidalis). This suggests that some Bombus species have a broader dietary range and are capable of pollinating various types of plants, including both native and non-native species. In contrast, other Bombus species are more selective in their foraging habits, focusing their interactions on a single category of plants. These findings provide insights into the ecological roles and foraging behavior of different bee species in the different elevational gradients. Certain Bombus species are referred to as generalists, demonstrating the ability to engage with a diverse range of plant types and ecological settings, while others function as specialists, concentrating their interactions on a specific category of plants within a particular landform. These differences in foraging behavior can have implications for pollination dynamics and the ecological roles of these bee species in the Chitwan Annapurna landscape. भमरा विशेषत उच्च भेगमा पाइने प्राकृतिक र कृषि प्रजातिका वनस्पतिहका महत्वपूर्ण परागसेचक हुन् । यिनीहरूको संख्या विश्वबाट कम हुँदै गईरहेकोले, नेपालमा यिनीहरूको दीर्घकालिन संरक्षणको लागि प्रजाति प्रचुरता, विचरण गर्ने वनस्पति र वातावरणीय असरबारे अध्ययन आवश्यक छ । यो अध्ययनले चितवन अन्नपूर्ण परिदृश्यमा पाईने भमरा प्रजातिको संरचना, र फूल फुल्ने विरुवासँग तिनीहरूको सम्बन्धको बारेमा अनुसन्धान गरेको थियो । यसको लागि २०१८ र २०१९ को धेरै फूल फुल्ने समयमा समुन्द्र सतहबाट ६००–३५०० मी. को उचाइसम्म कालीगण्डकी (मुस्ताङ तर्फ), मरस्याङदी (मनाङ तर्फ) र बुढीगण्डकी (गोरखा तर्फ) का पहुचवाला वाटाहरू प्रयोग गरिएको थियो । ती वाटाहरू थरिथरिका वासस्थानको किसिम (कृषि क्षेत्र, घाँसे मैदान, जंगल र करेसाबारी) हुँदै गुज्रन्थ्यो । भमराहरू जम्मा गर्नको लागि अनुसन्धान कर्ता ती वाटाहरूमा विस्तारै हिडे त्यस अवधिमा जुन प्वाइन्टमा भमरा देखिन्छ त्यहाँ रोकिएर २० मी. दायाँ र २० मी. बायाँ गर्दै ३० मीनेट बिताएका थिए र भेटिएका भमराहरूलाई इन्टोमोलोजिकल जाली र हातको सहायताबाट छोपेर जम्मा गरिएको थियो । सम्पूर्ण हिड्ने प्रकृया ३ पटक माथि जाने र ३ पटक तल झर्ने गरी तय गरियो । वनस्पति र भमरा संजालको अध्ययनको लागि ३ वटा ट्रान्जेक्टमा २/२ वटाका दरले समुन्द्र सतहबाट १७०० मी. र २८०० मी. उचाइमा ४० मी.x ४० मी. का ६ वटा प्लटहरू तयार गरिएको थियो र अध्ययन अवधिमा प्रत्येक प्लटमा १२ पटक भ्रमण गरियो । एक भ्रमणमा प्रत्यक प्लटमा ६० मीनेट विताइयो । त्यस अवधिमा जुन भमराले प्रजनन अंगलाई छुन्छ, त्यसलाई आधिकारीक भ्रमण मानी गणना गरियो । भमराहरू र फुलफुल्ने वनस्पतिका वर्गहरूलाई नेटवर्क प्रकृया द्वारा विश्लेषण गरियो जसमा उच्च तहमा १६ वटा भमरा प्रजातिहरू र तल्लो तहमा विरुवाका वर्गहरू (स्वदेशि र आयतित)ले प्रतिनिधित्व गरेको थियो । यस अध्ययन अवधि भर १६ वटा भमरा प्रजातिहरू पहिचान गरिएको थियो । यस्तै भमराहरूको सापेक्षित समृद्धि उचाइ, वासस्थान र खाद्यन वनस्पतीको प्रकार अनुसार फरक पाइयो । वी. हेमोरोइडालीस को सापेक्षित समृद्धि सबैभन्दा बढी n= १३४,२0.२९% त्यस्तै दोस्रो र तेस्रोमा वी. फेस्टिभस n= १२९,१९.५७% र वी. एग्जीमस n= १२४,१८.८४% थियो तर वी. व्रानिस्को, वी. नोभस र वी. प्रेसस जस्ता प्रजातिको सापेक्षित समृद्धि n= ५% थियो । भमराहरूको समृद्धिमा उचाइले पारेको असर (R=0.२८७६, p=0.000७) महत्वपूर्ण थियो । सबैभन्दा धेरै प्रजातिको विविधता मध्य उचाई (२००० मीं देखी ३००० मी. सम्म रेकर्ड गरिएको थियो । यसको कारण त्यस क्षेत्रमा फूलहरूको उपलब्धता अत्याधिक रहनु हो । त्यस्तै, गोरखा क्षेत्रको जंगली आवासमा (H=२.१८) प्रजाति विविधता उच्च थियो त्यसपछि मुस्ताङको घॉसे मैदानमा (H=२.१०) रेकर्ड गरियो । समग्रमा मनाङ र मुस्ताङमा भन्दा गोरखा ट्रान्जेक्टमा प्रजातिहरूको विविधता उच्च थियो । चितवन अन्नपूर्ण परिदृश्यमा भमराहरूको वितरण, विविधता र प्रजाति संरचना मुख्यत, आवास मोजेक, अल्टीच्युडनल ग्रयाडिन्ट र होस्ट वनस्पतिको श्रेणीले प्रभाव पार्दछ । अध्ययन गरिएका तीन नदीहरूका वेसीनमा पूर्व देखि पश्चिम सम्मको वातावरणीय परिवर्तनले वनस्पतिका विविधतामा फरकपन ल्याएको छ यसले चितवन अन्नपूर्ण परिदृश्यमा पाइने भमरा प्रजातिको समुदाय संरचनामा महत्वपूर्ण सम्बन्ध राखेको छ । अर्को तर्फ पूर्वी भागमा बढी वर्षा हुने तर पश्चिमी भागमा कम वर्षा हुने भएकोले पश्चिमी भाग सुख्खा छ । त्यसकारण विभिन्न किसिमका परागसेचन मैत्रिक फूलहरूका प्रजातिहरू पूर्व क्षेत्र (बुढी गण्डकी क्षेत्रमा) बढी पाइन्छ त्यसकारण भमराका प्रजातिहरू पनि यो क्षेत्रमा बढी पाइयो । यो अध्ययनले भमरा प्रजातिहरूको फुलमा विचरण गर्ने सम्बन्धलाई करेस्पोन्डीङ एनलाइसीस लिनियर मीक्स मोडल र कल्सटर एनलाइसीस मार्फत वनस्पतीको फ्यामिली, फूलको रंग र वनस्पतिका वर्ग (स्वदेशी र आयतित) द्वारा मापन गरिएको थियो । यो अध्ययनले वनस्पतिका फ्यामिली र फूलको रंग निस्चित भमराहरूले फूलहरू रोज्ने महत्वपूर्ण जैविक कारण हुन् भन्ने देखाएको छ । भमरा जातिहरूको विचरण तिव्रता तल्लो र माथिल्लो उचाइका विन्दुहरूमा स्थानिय र आयतित वर्गका वनस्पतिहरूमा महत्वपूर्ण र निश्चित थियो । भमरा र वनस्पतिका वर्णहरूको संजालको विश्लेषण गर्दा स्थानिय वनस्पतिका वर्गहरूमा आयतित वनस्पतिका वर्गहरूमा भन्दा बढी भमराहरूको प्रतिक्रिया रहयो । यसले निश्चित भमरा प्रजातिहरू (जस्तै, वि. एसियाटिकस, वि. हेमोरोइडालिस, वि. टुनिक्याटस, वि. एग्जीमस), का भमराहरू अधिक सामान्य हुन्छन् यस्ता जातिहरूको विसाल पोषणीय क्षेत्र हुन्छ र यिनीहरू विभिन्न थरीका वनस्पति हरू स्थानिय, आयतित दुवै विचरण गर्न सक्छन् । यो खोजले विभिन्न इलेभेसन ग्रयाडिन्टमा माहुरी प्रजातिहरूको पारिस्थीतीक भूमिका र विचरण प्रणाली माथि प्रकाश पारेको छ । यसले केही भमरा जातिहरू सामान्यपूर्ण हुने र विभिन्न प्रकारका वनस्पति र पारिस्थीतीक वनावटमा घुलमील गर्न सक्छन् । केही भमरा प्रजातिहरू विशेषज्ञ हुन्छन् र आफ्नो अन्तरकृयालाई विशेष भू–संरचना र विशिष्ट प्रकारका वनस्पतिका वर्गहरूमा केन्द्रित गरेको हुन्छन् । भमरा प्रजातिहरूको फूलको विचरणको फरक पनाले परागसेचन गर्ने बानीमा प्रभाव पार्दछ त्यसकारण चितवन अन्नपूर्ण परिदृश्यको पर्यावरणमा यिनीहरूको योगदान महत्वपूर्ण रहेको छ ।
Species Diversity and Distribution Pattern With Conservation Threats of Dragonflies (Odonata-Anisoptera) In Godawari, Lalitpur
(Department of Zoology Institute of Science and TechnologyTribhuvan University, Kirtipur, Kathmandu, 2006-11) Pokharel, Arjun Kumar
Not available.
Species Diversity and Ilabitat Preference of Herpetofauna in Lumbini Region, Nepal
(Institute of Science & Technology, 2023-01) Nepali, Pit Bahadur
The herpetofauna (amphibians and reptiles) are diverse and poikilothermic vertebrates that serve as excellent bio-indicators of stressed ecosystems. There is little information on the taxonomy, diversity, abundance, and distribution of herpetofauna in the Lumbini region. The aim of this study is to explore the species diversity and habitat preferences of herpetofauna in this region. The study was conducted from March 2016 to July 2020, in six districts. A total of 36 stations were chosen in these districts. From each station, sampling was done in five different habitats, namely agricultural fields, forests, riparian habitats, wetlands, and human habitats. Five transects, each of 200 m, were fixed in each habitat. In each transect, four quadrats of 20 m x 20 m were used for searching specimens using raking and digging methods. Additionally, pitfall, visual encounters, and opportunistic surveys were used to maximize the collections. The morphometric measurements and the use of specified keys, all species were classified at the species level. The abundance, species richness, diversity, and habitat preference were analyzed in Microsoft Excel, PAST (4.11 version), and R (version 3.6). Arc GIS was used to prepare a distribution map of herpetofauna. A total of 4,589 and 2,629 individuals of amphibians and reptiles were observed, respectively. There were 58 species of herpetofauna that included 17 species of amphibians and 41 species of reptiles. Amphibians included 12 genera and 6 families: Bufonidae, Megophryidae, Microhylidae, Ranidae, Rhacophoridae, and Ichthyophidae. Reptiles included 30 genera and 12 families: Crocodylidae, Trionychidae, Bataguridae, Agamidae, Gekkonidae, Varanidae, Scincidae, Typhlopidae, Boidae, Colubridae, Elapidae, and Viperidae. Euphlyctis cyanophlyctis, Minervarya nepalensis, Minervarya teraienesis, Duttaphrynus melanostictus, Hoplobatrachus tigerinus, and Microhyla ornate were highly observed individuals among amphibians, whereas Ichthyophis sikkimensis, Uperodon taprobanicus, Sphaerotheca breviceps, and Nanorana liebigii were least observed individuals among amphibians. The habitat-wise species richness of amphibians was 14, seven, 11, 16, and seven in agricultural fields, forests, human habitats, riparian areas, and wetland areas, respectively. D. melanostictus, D. stomaticus, E. cyanophlyctis, Hoplobatrachus, Minervarya species, and M. ornata were common species found in every study site. I. sikkimensis was a new distributional record among amphibians in the Lumbini region. Polypedates leucomystax was distributed in both the Terai and mountainous regions. Simpson's Index, Shannon index (H), and Pilou’s evenness (J) of amphibians were found to be the highest in riparian areas, whereas it was found the lowest in wetlands. Among reptiles, Calotes versicolor, Ptyas mucosa, and Xenochrophis piscator were the most observed species, whereas Crocodylus platuris was the only species observed throughout the survey period. C. versicolor is a widely distributed species, Laudakia tuberculata was found in the mountains, and turtles were found in the Terai region. Snakes were prevalent in human habitats and forests, while geckos dominated the lowlands, and skinks inhabited the forests only. C. palustris is a new distributional record of this region. The Simpson index, Shannon indices (H'), and Pilou’s evenness were recorded high in forests while low in wetlands. Among the 27 identified snakes, eight were venomous, and 19 were non-venomous. Three species of Boiga among non-venomous were semi-venomous. The present study shows that herpetofauna utilized more than two habitats and are also species-specific. Amphibians preferred riparian areas, while reptiles preferred the forest. These habitats were protected for the conservation of amphibians and reptiles. This area has a taxonomically rich herpetofauna, but C. palustris, Varanus flavescens, Python species, Oligodon erythrogaster, Trachischium tenuiceps, and Ophiophagus hannah were the least observed species and also marked as threatened species in the IUCN Red List of threatened species. The protection of these species is essential.
Taxonomic diversity and community structure of insect pollinators in Shivapuri-Nagarjun National Park, Central Nepal
(Institute of Science and Technology, Zoology, 2022) Dyola, Urmila
Insect pollinators are important agents mediating useful services for human and the ecosystem. Large number of wild plants and agricultural crops depend on the pollinators for their pollination. Global trend has shown decline of several taxa of pollinators and indicating habitat loss as major driving factor. Several studies have been done on pollinators in agricultural and natural areas however there are very few works describing their distribution and diversity in protected area despite the fact that these areas are globally important for preserving disturbance-intolerant pollinators. Wild flowering plants of the park may play an important role for conservation of pollinators. This study explored the taxonomic diversity and the community structure of insect pollinators; bees, butterflies, and hoverflies of Shivapuri-Nagarjun National Park (SNNP). Furthermore, five least collected wild bees during two years of survey were used as model pollinators to check the distribution. The research also documented plant-pollinators interaction to find out the key pollinators, plants that serve as hubs of pollinators, and seasonal variations of pollinators.The survey was done in SNNP for two consecutive years (2018–2019) in four different habitats; Open trail, Forest trail, Managed habitat, and Grassland using both belt transect and colored pan traps methods in three different elevations that ranges from 1,400m–2,700m. The results showed 42 and 34 species of bees and hoverflies respectively. Out of them, 11 species: Amegilla candida, A. fallax, A.insularis, A. quadrifasciata, Elaphropoda impatiens, Ceratina perforatrix, Colletes similis, Megachile conjuncta, Nomia iridescens, Xylocopa collaris, and X. violacea are new country records of bee and Graptomyza nigripes, Lycastris albipes, and Volucella trifasciata are new country records of hoverflies. Likewise, community structure of pollinators presented a total of 167 different species; the butterflies being the most dominant group (48.50%) followed by bees (29.94%) and hoverflies (21.56%). Diversity indices in alpha level was analysed; the Open trail was comparatively more diverse (4.85), followed by the Managed habitat (4.30). Whittaker Beta diversity analyzed the high species turnover between Forest trail and Managed habitat. Environmental variables like humidity, atmospheric temperature, and flower resources in different elevation have a significant effect (p<0.05) on pollinating insects. The species distribution model showed Nomada mutabilis, Thyreus decorus, T. himalayensis, Megachile femorata, and X. violacea are spread out across a broad region vii in the park. The accuracy of model predictions for all five bees are statistically well specified (AUC is greater than 0.07). The plant-pollinator interactions were complex and asymmetrical showing Eristalis tenax, E. cerealis, and Pieris canidia as key pollinators. Ageratina adenophora, Bidens pilosa, and Trifolium repens were observed as the most visited plants by pollinators. Seasonal comparisons showed that there is high species turnover of bees and hoverflies between spring and autumn seasons ( p<0.05). Based on these results, it is clear that the park provides suitable habitats for many species of pollinators. Open trials with a rich herb and shrub coverage can provide foraging habitat to pollinators. High diversity and abundance of insects in Open trial can aid good pollination service in this habitat. Other habitats like managed area, grassland, and forest can be important determinants of wild bees resulting different pollinator community. Frequent visits of pollinators in exotic plants compared to native plants could alter the native plant- pollinator interaction in long term if former plants are not managed.
Taxonomy, Species Diversity and Distribution Patterns of Ants of Nepal
(Faculty of Zoology, 2022) Subedi, Indra Prasad
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