Protected Landscape with Natural Habitat inside Urban Area Could Conserve Avifauna Biodiversity: A Long-term Study from an Overpopulated Subtropical Megacity

Protected Landscape with Natural Habitat inside Urban Area Could Conserve Avifauna Biodiversity: A Long-term Study from an Overpopulated Subtropical Megacity | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Protected Landscape with Natural Habitat inside Urban Area Could Conserve Avifauna Biodiversity: A Long-term Study from an Overpopulated Subtropical Megacity Ashikur Rahman Shome, Md. Fazle Rabbe, Mohammad Firoj Jaman, Nahla Khan, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4733401/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Natural habitats were converted to human-modified landscape as a result of urbanizations in metropolitan areas which resulting in alteration of avian species composition. Analyzing bird habitat preferences and seasonal dynamics can help us better understand how they adapt to changing environments. We used the point count approach at Bangladesh's National Botanical Garden to gain a thorough picture of how a protected landscape playing role in avian biodiversity conservation in a mega-populated, highly polluted city with experienced with extremely modified natural habitat. Along with impacts of habitat heterogeneity and temporal changes on avian community composition was also detected for this three years long survey. Observations based on habitat and seasonal trends revealed a diverse avifauna with 133 bird species (about 20 percent of the country's avifauna) and 5931 individuals belonging to 16 orders and 46 families. Richness and abundance of birds varied significantly among the habitats and season types. The highest richness, abundance and diversity indices was calculated for tree (H = 3.645, D = 0.966) and the pair-wise ANOVA test for habitats was significant only for tree. Red-vented Bulbul Pycnonotus cafer ranked as the most abundant species and we found seven generalist species based on their habitat preferences. Bird assemblages were richer in winter showed significant variation in pair-wise ANOVA test. Although bird diversity was found maximum in winter (H = 3.935, D = 0.976), evenness was calculated the highest for rainy season (E = 0.711 ) . The findings of this study demonstrated that bird variety is strongly linked to their various habitats and seasons. Avifaunal persistence was aided by habitat heterogeneity, which provided optimal foraging, roosting, and breeding options for birds. Diverse type of native plantations habitat and wetlands with natural habitat could aid in conservation of avian communities in urban area. The diversity of bird species revealed the ecosystems' intactness and ecological soundness. This finding provides the foundation for a long-term study of the bird-habitat connection and seasonal fluctuations. Bird Urban Community Ecology Habitat heterogeneity Season Conservation and Protected area Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction Conservation of the avifauna and their natural habitat is becoming the major concern to urban biodiversity conservationist throughout the world (Shochat et al. 2010 ). On the international scale, the population of metropolitan regions is growing faster than in other areas. Urbanization is a long-lasting trend characterized by significant human modifications to ecosystems, which turns naturally occurring green and blue areas into constructed buildings and impervious surfaces, ultimately leading to a decline in habitat specialist bird diversity and in parallel way the number of habitat generalized as well as scavenger birds are increasing (Rocha and fellows 2018, McKinney 2006 ). For this the anthropogenic stressor changing the avian communities gradually and the natural balance are destroying. In the urban landscape for conservation of birds protected landscape with natural habitat can play a significant role (Taylor et al. 2013 ). Bangladesh, the world’s largest deltaic region that lies at the intersection point of two tremendously enriched bio-geographical realms; Indo-Himalayan and Indo-China sub region that includes a great diversity wildlife and occupies three major vegetation’s which inhabits this exceptionally diversified ecosystems (Shome and Jaman 2021 ). Among wildlife this country is enriched with different types of avifauna and several studies from the last 40 years have provided the number of species which varies from 578 to 718 (IUCN 2015, Grimmett et al. 2021 ). Avifaunal diversity is one of the most important ecological indicators for estimating the health and quality of ecosystems (Sarkar et al. 2009 , Strohbach et al. 2009). Apart from being a part of food web, birds play a vital role in many crucial natural activities like pollination, seed dispersal and pest control (Jaman et al. 2024 ). But due to habitat loss and its subsequent effect on food and shelter, are posing as a threat for birds which are also compelling them to change their habitats (Grimmett et al. 2021 ). Some additional factors like the rapid increase of anthropogenic pollution, urbanization and other potential threatening factors are negatively affecting the population density of animals, causing habitat fragmentation, ecosystem and biodiversity degeneration and eventually diminishing the species richness; however, biomarkers like birds serve to illustrate these effects significantly (Chowdhury et al. 2021 a, Egwumah et al. 2017 ). Comprehensive and baseline studies on urban landscapes and eco-physiology are imperative for monitoring and conserving wildlife, especially birds (Rajia et al. 2015 , Islam et al. 2018 , Jaman et al. 2021 , 2022 , Shome et al. 2021a , 2021b 2022a ,b). Dhaka is a huge, over-populated metropolis which was once filled with wetlands, forests and grasslands, supporting a glorious wild fauna and was home to eagles, egrets, falcons, pheasants, waterfowls and many more regarding avifauna (Jaman et al. 2021 ). Dhaka city now provokes to disregard itself being an unre-formable wasteland although some researchers find it as a resilient urban zone that can be altered into a livable city by sustainable development planning (Sarkar et al. 2009 ). Some remarkable studies have been conducted in different region on Dhaka megacity in previous years (Shome et al. 2021b ). Unfortunately, the wildlife of Bangladesh is facing many notable threats and vanishing rapidly; with a view to protecting those experts have designed a network of protected areas in Bangladesh and among them, National Botanical Garden has been declared as a protected area under the wildlife act 1974 which is situated at the central region of Bangladesh in Dhaka (Khan 2018 ). National Botanical Garden has been prominently built for conserving plants even so it serves as an exemplary key-site for bird (Islam et al. 2014 ). At the same time as a protected green space in urban megacity this area is playing a significant role in bird conservation. Scientific studies on the status of avifauna in National Botanical Garden are still limited and the last one dated back 10 years (Islam et al. 2014 ) which was relatively short spanned. Present study has been implemented for a comparatively prolonged duration and oriented to provide updated and compiled information on the diversity, community structure, and habitat preference of avifauna an urban protected area situated in a megacity Dhaka. Methods Study area The study was conducted in the National Botanical Garden, located in Mirpur, the northeast region of Dhaka metropolitan, Bangladesh (Fig. 1). It is a protected area and the largest plant conservation center in the country, founded in 1961 (Chowdhury et al. 2021 ) for plant conservation and collection, later declared as a protected area under the wildlife act of Bangladesh 1974 (Amendment) with an area of about 0.85 square kilometer. About 1826 species of flora (e.g. trees, shrubs and herbs) including a large number of fauna are reported to be present here (Banglapedia 2021 ). It includes diverse habitats such as planted trees, ponds, lakes, open field, flower garden and ditches. It has been prominently built for plant conservation even so it serves as an exemplary key-site for bird watching. We categorized the habitats based on their physical features into four groups and these include- bush (BU), grassland (GL), tree (TR) and waterbody (WB) (Fig. 1). We collected data equally from each habitat to represent the whole study area. Figure 1. Study area map of National Botanical Garden, Mirpur Dhaka. Bird observations We collected data following point count survey (Hutto et al. 1986 , Bibby et al. 1992). We established eight point survey areas (~ 50-m radius) for each habitat types, multiplied up to total 32 (four habitat*8) point centers. At each point, we conducted surveys regularly in each season from March 2017 to February 2020 for a total of 288 (36*3*3) counts. The study period was divided into three seasons- summer (March-June), rainy (July - October) and winter (November - February) (Emrose et al. 2024 ). Surveys were performed via single observer spending five hours in the site, under suitable weather conditions. We detected birds by sight and sound and identified to species level following popular Bangladeshi field guide (Khan 2015 , Khan 2018 ). Birds were also classified as migratory or resident ( Appendix A ). Resident species were observed in the study area throughout the year. Migratory birds occurred seasonally, especially in summer or winter. We photographed birds with the help of DSLR camera (Canon 600d, Nikon D7100 and Nikon D500 with Camera with Canon EF-S 55–250 IS-II lens, Nikon Af-P 70–300 mm VR lens). Data analysis : Statistical analyses were carried out using spread sheet, Ms excel and PAST software. The species number and their individual number at every point were recorded and tabulated. The 'specpool' function from the Vegan Package (Oksanen et al., 2019) was implemented to estimate the total number of species in the study area using first and second-order Jackknife, Bootstrap, and Chao richness estimators. The relative abundance of particular bird species was calculated by dividing the number of individual of a species by the total number of individuals of all species multiplied by 100. Observation status of birds was calculated by following the formula Khan ( 2015 ). Fils et al. ( 2014 ) calculated the estimated number of species (x) based on the means of these four indices. Sampling completeness was then calculated using the following formula: Sampling completeness = the Observed number of species(n)/ Estimated number of species(x) ∗ 100. Species richness and total bird abundance in different habitats (Bush, Grassland, Water-body, Tree) and seasons were compared with one-way ANOVAs, followed by Tukey’s Honest Significant Difference (HSD) test for multiple comparisons (α = 0.05). The average species richness and abundance per season was summarized and presented in boxplot by habitats. Evenness was enumerated by dividing the diversity indices with the natural log of species richness. The diversity indices were calculated following Shannon-Wiener index (Shannon and Wiener 1949 ), Simpson's index (Simpson 1949) of diversity. Rank abundance plot was prepared to understand the patterns of dominance following Whittaker ( 1965 ). The habitat similarity plot or cluster analysis for microhabitats was performed following the method by Bray-Curtis index (1957). Result Bird community composition In this study, a total of 114 species of birds with 5931 individuals, belonging to 16 orders and 46 families were recorded (Appendix 1). Additionally 19 species was observed from the study area during the survey period but not in survey time. Among the total bird species, 59 (51.75%) species were passerine and 55 (48.24%) species were non-passerine. The most diverse order in terms of species number was Passeriformes with 59 species followed by Piciformes (8), Cuculiformes (7), Pelecaniformes (7). The most common families were Ardidae and Cuculidae with 7 species each. We recorded 86 resident and 28 migratory bird species during the study period. Among the migratory species, 25 were winter visitors, 2 were summer visitors ( Cuculus micropterus , Clamator jacobinus ) and 1 was passage visitor ( Larbivora brunea ). A detailed description on bird species checklist, is provided in the supplementary information (Appendix 1). The range of 127–146 species predicted by richness estimators is quite close to the 114 species that were actually spotted during the field trip. The fact that 83% of the samples were complete, showing that species sampling in the research area was adequate and some species are left to discover from the study area. The most abundant bird species was Pycnonotus cafer (Red-vented Bulbul, 306 individuals), Sturnus contra (Asian Pied Starling, 272 individuals), Acridotheres tristis (Common Myna, 266 individuals), Passer domesticus (House Sparrow, 232 individuals) and Turdoides striata (Jungle Bubbler, 226 individuals). The ten most dominant species constituted for 38.7% of total individuals whereas 40 least dominant species held only 1.07%. This signifies highly uneven distribution of species in the community which is explained in the rank abundance plot (Fig. 2 ). According to observation status of the recorded 114 species of bird during the survey time, 44(38.59%) bird were very common, 5(4.38%) were common, 27(23.23%) were uncommon and 38(33.33%) were rare. Among the bird species the most abundant bird was Red-vented Bulbul ( Pycnonotus cafér ), with highest relative abundance (5.15%). Habitat preference Avian species richness and abundance varied significantly among the habitats (Table 1 ). The maximum number of species was found in tree habitat and the pair-wise test for habitats was significant only for tree. Similarly, the high population (71.38% of total) levels in tree caused significant pair-wise variation between the tree-grassland, tree-bush and tree-water-body pair. The diversity indices showed highest diversity in tree habitat ( H = 3.645, D = 0.966 ) and evenness was lower for the tree ( E = 0.428 ). Table 1 One-way ANOVA results comparing species richness and abundance among seasons and habitats in NBG, Bangladesh. Tukey HSD multiple comparisons of means 95% family-wise confidence level. Effect F df p Effect F df p Richness in season 37.144 2 0.0004 Abundance in season 5.400 2 0.045 Rainy-Summer < 0.05 Rainy-Summer 0.574 Rainy-Winter < 0.01 Rainy-Winter < 0.05 Summer-Winter < 0.01 Summer-Winter 0.155 Richness in habitat 384.642 3 < 0.001 Abundance in habitat 66.535 3 < 0.001 Tree-Grassland < 0.01 Tree-Grassland < 0.01 Tree-Bush < 0.01 Tree-Bush < 0.01 Tree-Water body < 0.01 Tree-Water body < 0.01 Grassland-Bush 0.559 Grassland-Bush 0.265 Grassland-Water body 0.755 Grassland-Water body 0.883 Bush-Water body 0.899 Bush-Water body 0.590 We found some habitat specialist species and generalist species in this study showed in Fig. 3 A. A total of seven generalist species were observed using more than one habitat during the study. Among them, one occurred (Oriental Magpie Robin) in bush, grassland and tree; five (Large-billed Crow, House Sparrow, Jungle Myna, Asian Pied Starling, House Crow) in grassland and tree; one (Brahminy Kite) in tree and water-body. Among the habitat specialist species, 66.3% was observed in tree following 15.9% in bush, 13.5% in water-body and 4.8% in grassland respectively (Appendix 1). Bray-Curtis similarity index analysis was performed to determine the similarity among four types of microhabitat. In this index, grassland and tree formed the first clusters showing more similarities among the species of two types of microhabitats. A large cluster was formed between the species of first cluster and the species of bush. Bushy area’s species shows more similarity with the species of tree and ground where less similarity with the species of water-bodies (Fig. 4) . Figure 4. Similarity profile test among microhabitats using Bray-Curtis index (BU- Bush, T- Tree, G-Grassland, WB-Water Body). Seasonal variation The maximum and minimum number of bird species and individuals was recorded in winter and rainy season respectively, which differed distinctively (Table 1 ). Pair-wise test for species richness in all seasons varied significantly, whereas variation of abundance occurred due to the difference between rainy and winter (Table 1 ). The bird diversity was calculated the highest in winter (H = 3.935, D = 0.976) and the lowest in rainy (H = 3.629, D = 0.969) season. However, evenness was maximum in rainy (E = 0.711) and minimum in winter (0.528) signifying irregular distribution of species in winter season (Table 2 ). Among three season birds communities shows significant difference in Analysis of similarity (ANOSIM) test (R = 0.95, p-value = 0.0035) . This test also illustrate significant difference in winter season over the summer and rainy season in non-metric multidimensional plot (NMDs) with a stress level of 0.061 (< 0.2) (Fig. 5 ) for the presence of different groups of migratory birds in winter season. Table 2 Species richness, abundance, Simpson’s Index (D), Shannon-Weiner Index (H) and evenness (E) in different seasons and habitats. Category Parameters Richness Abundance D H E Season Rainy 53 1621 0.969 3.629 0.711 Summer 73 1884 0.971 3.769 0.593 Winter 97 2426 0.976 3.935 0.528 Habitat Bush 18 214 0.813 2.109 0.458 Grassland 11 856 0.837 1.971 0.653 Water body 15 627 0.814 1.859 0.428 Tree 78 4234 0.967 3.645 0.491 42.1% of the total species were found in all three seasons (Fig. 3 B). We found 13 species in two seasons and most of them (76.9%) were seen in summer-winter seasons. The highest number of unique species was observed in winter (69.8%), following summer (26.4%) and rainy (3.8%) respectively. Bird species richness per season ranged from 1 to 51 per count period (mean = 14.92 ± 16.79). The maximum total number of species was observed in tree habitat (mean = 43.22 ± 5.97) whereas the least was in bush (mean = 4.667 ± 3.651) (Fig. 6 A). Similar result was found for abundance of birds in habitats per season shown in Fig. 6 B. Discussion At present green and blue spaces in urban landscapes with diverse native plant species and natural habitat are playing significant role for holding resident and migratory species (Xiong et al. 2022 ). In urban areas, for the increasing number of human population and anthropogenic stressors a small amount of blue-green spaces remain with natural habitat and in those areas, the assemblage of wildlife species are comparatively higher (Prihandi and Nurvianto 2022 ). For this those spaces containing a higher conservation value for conserving the wild bird species and that’s statement also reflected in our study area. Observed overall 133 species birds are the about One-fifth portion (20%) of total bird species of Bangladesh (Khan 2018 ), 82% bird species of Megacity Dhaka (Jaman et al. 2021 ) and the previous works on avifauna in different parts of Dhaka Megacity enlisted fewer birds compared to this long term study (Jaman et al. 2021 , Shome et al. 2021b ). This study area is situated at the central area of Bangladesh inside a highly polluted and overpopulated city and during the migration period many forest-dwelling migratory bird as well as some aquatic migratory birds use this area as their resting place. Additionally, once this area was the part of a deciduous forest. So for all these reasons it can be said that National Botanical Garden, Mirpur, Dhaka provides an ideal habitat and feeding resources and for this, this area has become a sweet home of different groups of birds including resident and migratory ones because of diverse number of plant species and lakes. Besides others areas of Dhaka City are not protected but our study area is protected by national laws and strictly maintained under the Bangladesh forest department. For this, birds are facing less disturbances and threats than any other areas of Dhaka city (Shome et al. 2021b ). Previously a study was done in this study area but it was a short-term (6 months) study which reported only 65 species of bird and this study shows more species then previous (Islam et al. 2014 ). So it is clear that, in the urbanization process, large-sized protected areas with natural habitats can conserve resident and migratory bird species. The structure of habitat has a great influence in the community structure of the avifauna in the study area. The more diverse plants species could attract more bird species richness and diversity (Paker et al. 2014 ) is also reflected in this study also. The forest habitat of the study area is enriched with diverse plant species thus the number of avian species are higher in the study area. A similar study was conducted in a protected area (Bhawal National Park) near to the study site which holds 138 species of birds but the area of that study location was more than 5000ha and which is a renowned deciduous forest (Jaman et al. 2024 ). So the present study site is highly potential for holding diverse avian species and as an urban green space has higher conservation value. The most abundant bird species Pycnonotus cafer mainly feeds on fruits, grain, nectar, insects (Chishty et al., 2021 ) and get more opportunity for its livelihood in this study area because of the presence of diverse number of plant species providing enough food, shelter and nesting facilities for them. Study area is also an ideal habitat for insect’s thus highest number of observed birds species are insectivore (Fig. 2 ). This area is also important as the nesting side of different species of birds in Dhaka because there is a little place in Megacity Dhaka where birds can breed but breeding records of 46 species of birds in this study indicates that disturbance of this area is lower and the environment of this area is favorable for breeding of those resident birds species (Appendix 1). Though in urban area number of generalist bird species is higher because of anthropogenic food sources, but in the study area the number of specialist bird species is higher because of presence of diverse habitat and good account of natural food sources as well as opportunities (Fig. 3 A)(Keten et al. 2020 ). Due to the presence of winter migratory bird we found highest number of species richness in winter season with highest diversity index (Fig. 3 B) (Tzortzakaki et al., 2018 ; Karjee et al., 2020). Besides in the late winter some resident birds starts their breeding activities (eg. Psittacula krameri, Accipiter badius, Caprimulgus macrurus, Chalcophaps indica, Dendrocopos macei, Dinopium benghalense ). For this they are more visible at that time in a result the number of birds species are higher at that time and all of them a significant difference observed among the avian communities among the three season (Fig. 5 ). Yearly the richness, abundance and diversity were gradually declined during the study period. From 2018 we observed anthropogenic activities in this area; this could be one of the major causes of the bird species declining gradually in our study area. Because of a forest based area, different types of natural and planted tree species are present, and for this tree was the most used microhabitat by birds besides. Birds get shelter, food, roosting, resting and nesting site from trees. Besides there are some ponds and lake but these are not suitable for aquatic bird species; so, diversity is low here. We found some constructional activities around the lake and pond for decorating the area and probably it is one of the regions with low diversity in aquatic habitats (Fig. 6 ). Now-a-days people in urban areas of Dhaka are fond of visiting this area and this number is gradually increasing. But people are not aware about the disturbances of wild animal, sound pollution especially in holidays and plastic pollution has become major threats of this garden. In our observation we have found some photographer destroyed the nest and habitat of birds only for getting good qualities of photos. National Botanical Garden is not only a place with diverse plant species but also different group of wildlife species specially birds. Authorities need to give proper concentration to conserve them and need to take proper planning system. In Megacity Dhaka it is becoming very difficult to survive for different groups of wildlife in polluted habitat where National Botanical garden shelters 133 species of birds. It’s time to take proper action to protect those urban birds. Conclusion This three-year long term study provides the scenario of the avian community, seasonality and habitat preference in National Botanical Garden Mirpur. Dhaka. The diversity of avifauna is higher and in winter season a number of winter migratory bird species is present in the study area. Recently human activities and disturbance has become a great problem to the avifauna of this area. As an area for recreation on holidays, a huge number of people come to this garden for refreshment, picnic, shooting but unfortunately maximum of them are not aware about the biodiversity of this area and disturbances created by them. Disposal of waste materials such as plastics, polythenes, styrofoam food boxes, chips packets and other garbage in aquatic and terrestrial habitats, sound pollution, plastic pollution is becoming a great concern for the bird species in the study area. Re-construction of water body, construction work and development activities in 2018 and 2019 is probably one of the major cause of low diversity of birds in respected years. Proper planning and management for the bird species is emergence beside plants with strict maintenance. Declarations Conflict of interest The authors have no relevant financial or nonfinancial interests to disclose. Acknowledgements We express our gratitude to the authority of National Botanical Garden and forest department for helping and giving us permission for field work in the study area. We are also grateful to Md.Tanvir Mia, Shofiul Alam and number of volunteers for their participation during field visit. Funding: This study was totally self-funded. 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Shome AR, Rabbe MF, Alam MM, Emon SF et al., (2022a) Avifauna in an urban landscape of a Lower Ganges District of Bangladesh: community structure, seasonality, habitat preference and conservation issues. Dhaka Univ J Biol Sci 31: 343–360. Shome AR, Jaman MF (2021) Diversity and seasonal occurrence of vertebrate wildlife at a rural site of Bangladesh: Threats and conservation issue. J Biodivers Conserv Biores Manag 7: 61-72. Simpson FB (1882) Notes on birds found near Dacca. Ibis. 4:84-95. Taylor L, Taylor C, Davis A (2013) The impact of urbanisation on avian species: The inextricable link between people and birds. Urban Ecosyst 16: 481-498. Tzortzakaki O, Kati V, Kassara C, Tietze DT, Giokas S (2018) Seasonal patterns of urban bird diversity in a Mediterranean coastal city: the positive role of open green spaces. Urban ecosyst 21: 27-39. Whittaker RH (1965) Dominance and diversity in land plant communities: numerical relations of species express the importance of competition in community function and evolution. Science 147: 250-260. Xiong Y, Li Z, Ruan L, Dai S, Hu, L (2022) Comparison of avian diversity between urban parks adjacent to mountain and river in the largest megacity Guangzhou, South China. Urban For. Urban Green 77: 127756. Additional Declarations No competing interests reported. Supplementary Files Supplementarymaterial.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4733401","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":341557099,"identity":"63821c15-0272-477c-a33b-a82fb16595cd","order_by":0,"name":"Ashikur Rahman Shome","email":"","orcid":"","institution":"University of Dhaka","correspondingAuthor":false,"prefix":"","firstName":"Ashikur","middleName":"Rahman","lastName":"Shome","suffix":""},{"id":341557101,"identity":"d5f775b0-3a21-48e2-8990-c2db55fcf85c","order_by":1,"name":"Md. Fazle Rabbe","email":"","orcid":"","institution":"University of Dhaka","correspondingAuthor":false,"prefix":"","firstName":"Md.","middleName":"Fazle","lastName":"Rabbe","suffix":""},{"id":341557102,"identity":"2cbc423b-c5d9-486a-a92d-7e3de8f58099","order_by":2,"name":"Mohammad Firoj Jaman","email":"","orcid":"","institution":"University of Dhaka","correspondingAuthor":false,"prefix":"","firstName":"Mohammad","middleName":"Firoj","lastName":"Jaman","suffix":""},{"id":341557103,"identity":"f5ab15ea-2afb-4c5b-b1b1-764a9d7cd762","order_by":3,"name":"Nahla Khan","email":"","orcid":"","institution":"University of Dhaka","correspondingAuthor":false,"prefix":"","firstName":"Nahla","middleName":"","lastName":"Khan","suffix":""},{"id":341557104,"identity":"cd1e29be-28f6-4c38-9ccf-938577e24ff7","order_by":4,"name":"Md. Aminul Islam","email":"","orcid":"","institution":"Stamford University","correspondingAuthor":false,"prefix":"","firstName":"Md.","middleName":"Aminul","lastName":"Islam","suffix":""},{"id":341557105,"identity":"0dff9a7a-00ad-4101-b97b-cc8832ffcc21","order_by":5,"name":"Md. Mahabub Alam","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA1ElEQVRIiWNgGAWjYFACHgZmBoYDIBbjAx6oiASxWpgNSNbCJkGUFt32swc/F7bdYZBvbz5W8baNQZ6/gffgDXxazM7kJUvPbHvGwNhzLO3m3DYGwxkH+JIt8Go5kGMgzdt2mIFZIsfsNm8bA+MGBh4zvA4zO//G+DdICxtQSzFQiz1hLTdyzMC28AC1MAO1JBKh5Y2Z9Yxzz3gkeI4lS845J5E84zAhv5zPMb5dUHZHDhhiBz+8KbOx7W/vxR9iMMADpYFOYiZG/SgYBaNgFIwCvAAA2AxDbowQjagAAAAASUVORK5CYII=","orcid":"","institution":"University of Dhaka","correspondingAuthor":true,"prefix":"","firstName":"Md.","middleName":"Mahabub","lastName":"Alam","suffix":""}],"badges":[],"createdAt":"2024-07-13 04:38:27","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4733401/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4733401/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":62944488,"identity":"ed4e648a-49e5-432b-9e16-089750dd166c","added_by":"auto","created_at":"2024-08-21 10:07:09","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":206302,"visible":true,"origin":"","legend":"\u003cp\u003eStudy area map of National Botanical Garden, Mirpur Dhaka.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4733401/v1/56ac5f47ea4e20f5a75177ad.png"},{"id":62945526,"identity":"fe3e64b2-5b01-4b73-92ed-d519e7db2e1d","added_by":"auto","created_at":"2024-08-21 10:23:09","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":13931,"visible":true,"origin":"","legend":"\u003cp\u003eRank abundance plot for species recorded from the study site. The y axis shows the relative abundance and the x axis ranks the species in order of their abundance from highest to lowest.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-4733401/v1/2ee13ef280390cdd5221e5cd.png"},{"id":62944489,"identity":"040e1b0a-f701-4f4b-bcc9-9f3481e1a170","added_by":"auto","created_at":"2024-08-21 10:07:09","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":118755,"visible":true,"origin":"","legend":"\u003cp\u003eVenn diagram showing the number of shared and unique species in four habitats and three seasons.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-4733401/v1/6393fcd5c387ab31457654c1.png"},{"id":62945986,"identity":"acceaeea-d0de-4e29-ad42-ccadd435766c","added_by":"auto","created_at":"2024-08-21 10:31:09","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":18622,"visible":true,"origin":"","legend":"\u003cp\u003eSimilarity profile test among microhabitats using Bray-Curtis index (BU- Bush, T- Tree, G-Grassland, WB-Water Body).\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-4733401/v1/78caf0f3b3badc4cf6682748.png"},{"id":62944494,"identity":"51162198-6c96-4dbf-88cd-6f9e8336ebb6","added_by":"auto","created_at":"2024-08-21 10:07:09","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":105607,"visible":true,"origin":"","legend":"\u003cp\u003eNon-metric multidimensional plot (based on the Bray-Curtis similarity index) showing separation of bird communities among three season (Pink circle indicates the winter season, blue indicates summer and green indicates rainy season).\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-4733401/v1/35fba7fba4b4e17fdca9878b.png"},{"id":62945057,"identity":"617f9ecb-8567-49a5-8b98-474c15505bb3","added_by":"auto","created_at":"2024-08-21 10:15:09","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":90809,"visible":true,"origin":"","legend":"\u003cp\u003eBox plot graph of species richness (A) and bird abundance (B) by habitats per season. Species richness and abundance were higher in tree than other habitats.\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-4733401/v1/f27a9c0826eb53404d891abd.png"},{"id":82013271,"identity":"03f8c0a0-3945-42fd-9b27-af2039d1a7c1","added_by":"auto","created_at":"2025-05-06 02:24:46","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1160695,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4733401/v1/16e4d001-5e71-42ac-af1c-78c8c8ba1dc9.pdf"},{"id":62945055,"identity":"5fb5a62c-033a-41e1-843f-fdf70ad4479f","added_by":"auto","created_at":"2024-08-21 10:15:09","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":27596,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementarymaterial.docx","url":"https://assets-eu.researchsquare.com/files/rs-4733401/v1/88234e5e8b9eb28572452927.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Protected Landscape with Natural Habitat inside Urban Area Could Conserve Avifauna Biodiversity: A Long-term Study from an Overpopulated Subtropical Megacity","fulltext":[{"header":"Introduction","content":"\u003cp\u003eConservation of the avifauna and their natural habitat is becoming the major concern to urban biodiversity conservationist throughout the world (Shochat et al. \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). On the international scale, the population of metropolitan regions is growing faster than in other areas. Urbanization is a long-lasting trend characterized by significant human modifications to ecosystems, which turns naturally occurring green and blue areas into constructed buildings and impervious surfaces, ultimately leading to a decline in habitat specialist bird diversity and in parallel way the number of habitat generalized as well as scavenger birds are increasing (Rocha and fellows 2018, McKinney \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). For this the anthropogenic stressor changing the avian communities gradually and the natural balance are destroying. In the urban landscape for conservation of birds protected landscape with natural habitat can play a significant role (Taylor et al. \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2013\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eBangladesh, the world\u0026rsquo;s largest deltaic region that lies at the intersection point of two tremendously enriched bio-geographical realms; Indo-Himalayan and Indo-China sub region that includes a great diversity wildlife and occupies three major vegetation\u0026rsquo;s which inhabits this exceptionally diversified ecosystems (Shome and Jaman \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Among wildlife this country is enriched with different types of avifauna and several studies from the last 40 years have provided the number of species which varies from 578 to 718 (IUCN 2015, Grimmett et al. \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Avifaunal diversity is one of the most important ecological indicators for estimating the health and quality of ecosystems (Sarkar et al. \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2009\u003c/span\u003e, Strohbach et al. 2009). Apart from being a part of food web, birds play a vital role in many crucial natural activities like pollination, seed dispersal and pest control (Jaman et al. \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). But due to habitat loss and its subsequent effect on food and shelter, are posing as a threat for birds which are also compelling them to change their habitats (Grimmett et al. \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Some additional factors like the rapid increase of anthropogenic pollution, urbanization and other potential threatening factors are negatively affecting the population density of animals, causing habitat fragmentation, ecosystem and biodiversity degeneration and eventually diminishing the species richness; however, biomarkers like birds serve to illustrate these effects significantly (Chowdhury et al. \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2021\u003c/span\u003ea, Egwumah et al. \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). Comprehensive and baseline studies on urban landscapes and eco-physiology are imperative for monitoring and conserving wildlife, especially birds (Rajia et al. \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2015\u003c/span\u003e, Islam et al. \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2018\u003c/span\u003e, Jaman et al. \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2021\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2022\u003c/span\u003e, Shome et al. \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2021a\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2021b\u003c/span\u003e \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2022a\u003c/span\u003e,b).\u003c/p\u003e \u003cp\u003eDhaka is a huge, over-populated metropolis which was once filled with wetlands, forests and grasslands, supporting a glorious wild fauna and was home to eagles, egrets, falcons, pheasants, waterfowls and many more regarding avifauna (Jaman et al. \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Dhaka city now provokes to disregard itself being an unre-formable wasteland although some researchers find it as a resilient urban zone that can be altered into a livable city by sustainable development planning (Sarkar et al. \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2009\u003c/span\u003e). Some remarkable studies have been conducted in different region on Dhaka megacity in previous years (Shome et al. \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2021b\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eUnfortunately, the wildlife of Bangladesh is facing many notable threats and vanishing rapidly; with a view to protecting those experts have designed a network of protected areas in Bangladesh and among them, National Botanical Garden has been declared as a protected area under the wildlife act 1974 which is situated at the central region of Bangladesh in Dhaka (Khan \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). National Botanical Garden has been prominently built for conserving plants even so it serves as an exemplary key-site for bird (Islam et al. \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). At the same time as a protected green space in urban megacity this area is playing a significant role in bird conservation. Scientific studies on the status of avifauna in National Botanical Garden are still limited and the last one dated back 10 years (Islam et al. \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2014\u003c/span\u003e) which was relatively short spanned. Present study has been implemented for a comparatively prolonged duration and oriented to provide updated and compiled information on the diversity, community structure, and habitat preference of avifauna an urban protected area situated in a megacity Dhaka.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e \u003cstrong\u003eStudy area\u003c/strong\u003e \u003cp\u003eThe study was conducted in the National Botanical Garden, located in Mirpur, the northeast region of Dhaka metropolitan, Bangladesh (Fig.\u0026nbsp;1). It is a protected area and the largest plant conservation center in the country, founded in 1961 (Chowdhury et al. \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2021\u003c/span\u003e) for plant conservation and collection, later declared as a protected area under the wildlife act of Bangladesh 1974 (Amendment) with an area of about 0.85 square kilometer. About 1826 species of flora (e.g. trees, shrubs and herbs) including a large number of fauna are reported to be present here (Banglapedia \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). It includes diverse habitats such as planted trees, ponds, lakes, open field, flower garden and ditches. It has been prominently built for plant conservation even so it serves as an exemplary key-site for bird watching. We categorized the habitats based on their physical features into four groups and these include- bush (BU), grassland (GL), tree (TR) and waterbody (WB) (Fig.\u0026nbsp;1). We collected data equally from each habitat to represent the whole study area.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Taba\" border=\"1\"\u003e \u003ccolgroup cols=\"1\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eFigure\u0026nbsp;1.\u003c/b\u003e Study area map of National Botanical Garden, Mirpur Dhaka.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eBird observations\u003c/strong\u003e \u003cp\u003eWe collected data following point count survey (Hutto et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e1986\u003c/span\u003e, Bibby et al. 1992). We established eight point survey areas (~\u0026thinsp;50-m radius) for each habitat types, multiplied up to total 32 (four habitat*8) point centers. At each point, we conducted surveys regularly in each season from March 2017 to February 2020 for a total of 288 (36*3*3) counts. The study period was divided into three seasons- summer (March-June), rainy (July - October) and winter (November - February) (Emrose et al. \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). Surveys were performed via single observer spending five hours in the site, under suitable weather conditions. We detected birds by sight and sound and identified to species level following popular Bangladeshi field guide (Khan \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2015\u003c/span\u003e, Khan \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). Birds were also classified as migratory or resident (\u003cspan refid=\"Sec6\" class=\"InternalRef\"\u003eAppendix A\u003c/span\u003e). Resident species were observed in the study area throughout the year. Migratory birds occurred seasonally, especially in summer or winter. We photographed birds with the help of DSLR camera (Canon 600d, Nikon D7100 and Nikon D500 with Camera with Canon EF-S 55\u0026ndash;250 IS-II lens, Nikon Af-P 70\u0026ndash;300 mm VR lens).\u003c/p\u003e \u003c/p\u003e \u003cp\u003e\u003cb\u003eData analysis\u003c/b\u003e: Statistical analyses were carried out using spread sheet, Ms excel and PAST software. The species number and their individual number at every point were recorded and tabulated. The 'specpool' function from the Vegan Package (Oksanen et al., 2019) was implemented to estimate the total number of species in the study area using first and second-order Jackknife, Bootstrap, and Chao richness estimators. The relative abundance of particular bird species was calculated by dividing the number of individual of a species by the total number of individuals of all species multiplied by 100. Observation status of birds was calculated by following the formula Khan (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). Fils et al. (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2014\u003c/span\u003e) calculated the estimated number of species (x) based on the means of these four indices. Sampling completeness was then calculated using the following formula: Sampling completeness\u0026thinsp;=\u0026thinsp;the Observed number of species(n)/ Estimated number of species(x) \u0026lowast; 100. Species richness and total bird abundance in different habitats (Bush, Grassland, Water-body, Tree) and seasons were compared with one-way ANOVAs, followed by Tukey\u0026rsquo;s Honest Significant Difference (HSD) test for multiple comparisons (α\u0026thinsp;=\u0026thinsp;0.05). The average species richness and abundance per season was summarized and presented in boxplot by habitats. Evenness was enumerated by dividing the diversity indices with the natural log of species richness. The diversity indices were calculated following Shannon-Wiener index (Shannon and Wiener \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e1949\u003c/span\u003e), Simpson's index (Simpson 1949) of diversity. Rank abundance plot was prepared to understand the patterns of dominance following Whittaker (\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e1965\u003c/span\u003e). The habitat similarity plot or cluster analysis for microhabitats was performed following the method by Bray-Curtis index (1957).\u003c/p\u003e"},{"header":"Result","content":"\u003cp\u003e \u003cstrong\u003eBird community composition\u003c/strong\u003e \u003cp\u003eIn this study, a total of 114 species of birds with 5931 individuals, belonging to 16 orders and 46 families were recorded (Appendix 1). Additionally 19 species was observed from the study area during the survey period but not in survey time. Among the total bird species, 59 (51.75%) species were passerine and 55 (48.24%) species were non-passerine. The most diverse order in terms of species number was Passeriformes with 59 species followed by Piciformes (8), Cuculiformes (7), Pelecaniformes (7). The most common families were Ardidae and Cuculidae with 7 species each. We recorded 86 resident and 28 migratory bird species during the study period. Among the migratory species, 25 were winter visitors, 2 were summer visitors (\u003cem\u003eCuculus micropterus\u003c/em\u003e, \u003cem\u003eClamator jacobinus\u003c/em\u003e) and 1 was passage visitor (\u003cem\u003eLarbivora brunea\u003c/em\u003e). A detailed description on bird species checklist, is provided in the supplementary information (Appendix 1). The range of 127\u0026ndash;146 species predicted by richness estimators is quite close to the 114 species that were actually spotted during the field trip. The fact that 83% of the samples were complete, showing that species sampling in the research area was adequate and some species are left to discover from the study area. The most abundant bird species was \u003cem\u003ePycnonotus cafer\u003c/em\u003e (Red-vented Bulbul, 306 individuals), \u003cem\u003eSturnus contra\u003c/em\u003e (Asian Pied Starling, 272 individuals), \u003cem\u003eAcridotheres tristis\u003c/em\u003e (Common Myna, 266 individuals), \u003cem\u003ePasser domesticus\u003c/em\u003e (House Sparrow, 232 individuals) and \u003cem\u003eTurdoides striata\u003c/em\u003e (Jungle Bubbler, 226 individuals).\u003c/p\u003e \u003c/p\u003e \u003cp\u003eThe ten most dominant species constituted for 38.7% of total individuals whereas 40 least dominant species held only 1.07%. This signifies highly uneven distribution of species in the community which is explained in the rank abundance plot (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eAccording to observation status of the recorded 114 species of bird during the survey time, 44(38.59%) bird were very common, 5(4.38%) were common, 27(23.23%) were uncommon and 38(33.33%) were rare. Among the bird species the most abundant bird was Red-vented Bulbul (\u003cem\u003ePycnonotus caf\u0026eacute;r\u003c/em\u003e), with highest relative abundance (5.15%).\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eHabitat preference\u003c/strong\u003e \u003cp\u003eAvian species richness and abundance varied significantly among the habitats (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The maximum number of species was found in tree habitat and the pair-wise test for habitats was significant only for tree. Similarly, the high population (71.38% of total) levels in tree caused significant pair-wise variation between the tree-grassland, tree-bush and tree-water-body pair. The diversity indices showed highest diversity in tree habitat (\u003cem\u003eH\u0026thinsp;=\u0026thinsp;3.645, D\u0026thinsp;=\u0026thinsp;0.966\u003c/em\u003e) and evenness was lower for the tree (\u003cem\u003eE\u0026thinsp;=\u0026thinsp;0.428\u003c/em\u003e).\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eOne-way ANOVA results comparing species richness and abundance among seasons and habitats in NBG, Bangladesh. Tukey HSD multiple comparisons of means 95% family-wise confidence level.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEffect\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003edf\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eEffect\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003eF\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003edf\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRichness in season\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e37.144\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.0004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eAbundance in season\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e5.400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.045\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRainy-Summer\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eRainy-Summer\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.574\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRainy-Winter\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eRainy-Winter\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.05\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSummer-Winter\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSummer-Winter\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.155\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRichness in habitat\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e384.642\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eAbundance in habitat\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e66.535\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTree-Grassland\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTree-Grassland\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTree-Bush\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTree-Bush\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTree-Water body\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTree-Water body\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrassland-Bush\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.559\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eGrassland-Bush\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.265\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrassland-Water body\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.755\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eGrassland-Water body\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.883\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBush-Water body\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.899\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eBush-Water body\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.590\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eWe found some habitat specialist species and generalist species in this study showed in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003eA. A total of seven generalist species were observed using more than one habitat during the study. Among them, one occurred (Oriental Magpie Robin) in bush, grassland and tree; five (Large-billed Crow, House Sparrow, Jungle Myna, Asian Pied Starling, House Crow) in grassland and tree; one (Brahminy Kite) in tree and water-body. Among the habitat specialist species, 66.3% was observed in tree following 15.9% in bush, 13.5% in water-body and 4.8% in grassland respectively (Appendix 1).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eBray-Curtis similarity index analysis was performed to determine the similarity among four types of microhabitat. In this index, grassland and tree formed the first clusters showing more similarities among the species of two types of microhabitats. A large cluster was formed between the species of first cluster and the species of bush. Bushy area\u0026rsquo;s species shows more similarity with the species of tree and ground where less similarity with the species of water-bodies (Fig.\u0026nbsp;4)\u003c/p\u003e \u003cp\u003e.\u003c/p\u003e \u003cp\u003e \u003cb\u003eFigure\u0026nbsp;4.\u003c/b\u003e Similarity profile test among microhabitats using Bray-Curtis index (BU- Bush, T- Tree, G-Grassland, WB-Water Body).\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eSeasonal variation\u003c/strong\u003e \u003cp\u003eThe maximum and minimum number of bird species and individuals was recorded in winter and rainy season respectively, which differed distinctively (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Pair-wise test for species richness in all seasons varied significantly, whereas variation of abundance occurred due to the difference between rainy and winter (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The bird diversity was calculated the highest in winter (H\u0026thinsp;=\u0026thinsp;3.935, D\u0026thinsp;=\u0026thinsp;0.976) and the lowest in rainy (H\u0026thinsp;=\u0026thinsp;3.629, D\u0026thinsp;=\u0026thinsp;0.969) season. However, evenness was maximum in rainy (E\u0026thinsp;=\u0026thinsp;0.711) and minimum in winter (0.528) signifying irregular distribution of species in winter season (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Among three season birds communities shows significant difference in Analysis of similarity (ANOSIM) test \u003cem\u003e(R\u0026thinsp;=\u0026thinsp;0.95, p-value\u0026thinsp;=\u0026thinsp;0.0035)\u003c/em\u003e. This test also illustrate significant difference in winter season over the summer and rainy season in non-metric multidimensional plot (NMDs) with a stress level of 0.061 (\u0026lt;\u0026thinsp;0.2) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e5\u003c/span\u003e) for the presence of different groups of migratory birds in winter season.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSpecies richness, abundance, Simpson\u0026rsquo;s Index (D), Shannon-Weiner Index (H) and evenness (E) in different seasons and habitats.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCategory\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eParameters\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRichness\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAbundance\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eD\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eH\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eE\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eSeason\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRainy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1621\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.969\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3.629\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.711\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSummer\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1884\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.971\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3.769\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.593\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWinter\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e97\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e2426\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.976\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e3.935\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.528\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003eHabitat\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBush\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e214\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.813\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2.109\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.458\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGrassland\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e856\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.837\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.971\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.653\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWater body\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e627\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.814\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.859\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.428\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTree\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e78\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e4234\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.967\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e3.645\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.491\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e42.1% of the total species were found in all three seasons (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003eB). We found 13 species in two seasons and most of them (76.9%) were seen in summer-winter seasons. The highest number of unique species was observed in winter (69.8%), following summer (26.4%) and rainy (3.8%) respectively. Bird species richness per season ranged from 1 to 51 per count period (mean\u0026thinsp;=\u0026thinsp;14.92\u0026thinsp;\u0026plusmn;\u0026thinsp;16.79). The maximum total number of species was observed in tree habitat (mean\u0026thinsp;=\u0026thinsp;43.22\u0026thinsp;\u0026plusmn;\u0026thinsp;5.97) whereas the least was in bush (mean\u0026thinsp;=\u0026thinsp;4.667\u0026thinsp;\u0026plusmn;\u0026thinsp;3.651) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e6\u003c/span\u003eA). Similar result was found for abundance of birds in habitats per season shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e6\u003c/span\u003eB.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eAt present green and blue spaces in urban landscapes with diverse native plant species and natural habitat are playing significant role for holding resident and migratory species (Xiong et al. \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). In urban areas, for the increasing number of human population and anthropogenic stressors a small amount of blue-green spaces remain with natural habitat and in those areas, the assemblage of wildlife species are comparatively higher (Prihandi and Nurvianto \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). For this those spaces containing a higher conservation value for conserving the wild bird species and that\u0026rsquo;s statement also reflected in our study area.\u003c/p\u003e \u003cp\u003eObserved overall 133 species birds are the about One-fifth portion (20%) of total bird species of Bangladesh (Khan \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), 82% bird species of Megacity Dhaka (Jaman et al. \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2021\u003c/span\u003e) and the previous works on avifauna in different parts of Dhaka Megacity enlisted fewer birds compared to this long term study (Jaman et al. \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2021\u003c/span\u003e, Shome et al. \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2021b\u003c/span\u003e). This study area is situated at the central area of Bangladesh inside a highly polluted and overpopulated city and during the migration period many forest-dwelling migratory bird as well as some aquatic migratory birds use this area as their resting place. Additionally, once this area was the part of a deciduous forest. So for all these reasons it can be said that National Botanical Garden, Mirpur, Dhaka provides an ideal habitat and feeding resources and for this, this area has become a sweet home of different groups of birds including resident and migratory ones because of diverse number of plant species and lakes. Besides others areas of Dhaka City are not protected but our study area is protected by national laws and strictly maintained under the Bangladesh forest department. For this, birds are facing less disturbances and threats than any other areas of Dhaka city (Shome et al. \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2021b\u003c/span\u003e). Previously a study was done in this study area but it was a short-term (6 months) study which reported only 65 species of bird and this study shows more species then previous (Islam et al. \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). So it is clear that, in the urbanization process, large-sized protected areas with natural habitats can conserve resident and migratory bird species. The structure of habitat has a great influence in the community structure of the avifauna in the study area. The more diverse plants species could attract more bird species richness and diversity (Paker et al. \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2014\u003c/span\u003e) is also reflected in this study also. The forest habitat of the study area is enriched with diverse plant species thus the number of avian species are higher in the study area. A similar study was conducted in a protected area (Bhawal National Park) near to the study site which holds 138 species of birds but the area of that study location was more than 5000ha and which is a renowned deciduous forest (Jaman et al. \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). So the present study site is highly potential for holding diverse avian species and as an urban green space has higher conservation value.\u003c/p\u003e \u003cp\u003eThe most abundant bird species \u003cem\u003ePycnonotus cafer\u003c/em\u003e mainly feeds on fruits, grain, nectar, insects (Chishty et al., \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2021\u003c/span\u003e) and get more opportunity for its livelihood in this study area because of the presence of diverse number of plant species providing enough food, shelter and nesting facilities for them. Study area is also an ideal habitat for insect\u0026rsquo;s thus highest number of observed birds species are insectivore (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e2\u003c/span\u003e). This area is also important as the nesting side of different species of birds in Dhaka because there is a little place in Megacity Dhaka where birds can breed but breeding records of 46 species of birds in this study indicates that disturbance of this area is lower and the environment of this area is favorable for breeding of those resident birds species (Appendix 1). Though in urban area number of generalist bird species is higher because of anthropogenic food sources, but in the study area the number of specialist bird species is higher because of presence of diverse habitat and good account of natural food sources as well as opportunities (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003eA)(Keten et al. \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eDue to the presence of winter migratory bird we found highest number of species richness in winter season with highest diversity index (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003eB) (Tzortzakaki et al., \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Karjee et al., 2020). Besides in the late winter some resident birds starts their breeding activities (eg. \u003cem\u003ePsittacula krameri, Accipiter badius, Caprimulgus macrurus, Chalcophaps indica, Dendrocopos macei, Dinopium benghalense\u003c/em\u003e). For this they are more visible at that time in a result the number of birds species are higher at that time and all of them a significant difference observed among the avian communities among the three season (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e5\u003c/span\u003e). Yearly the richness, abundance and diversity were gradually declined during the study period. From 2018 we observed anthropogenic activities in this area; this could be one of the major causes of the bird species declining gradually in our study area. Because of a forest based area, different types of natural and planted tree species are present, and for this tree was the most used microhabitat by birds besides. Birds get shelter, food, roosting, resting and nesting site from trees. Besides there are some ponds and lake but these are not suitable for aquatic bird species; so, diversity is low here. We found some constructional activities around the lake and pond for decorating the area and probably it is one of the regions with low diversity in aquatic habitats (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eNow-a-days people in urban areas of Dhaka are fond of visiting this area and this number is gradually increasing. But people are not aware about the disturbances of wild animal, sound pollution especially in holidays and plastic pollution has become major threats of this garden. In our observation we have found some photographer destroyed the nest and habitat of birds only for getting good qualities of photos. National Botanical Garden is not only a place with diverse plant species but also different group of wildlife species specially birds. Authorities need to give proper concentration to conserve them and need to take proper planning system. In Megacity Dhaka it is becoming very difficult to survive for different groups of wildlife in polluted habitat where National Botanical garden shelters 133 species of birds. It\u0026rsquo;s time to take proper action to protect those urban birds.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis three-year long term study provides the scenario of the avian community, seasonality and habitat preference in National Botanical Garden Mirpur. Dhaka. The diversity of avifauna is higher and in winter season a number of winter migratory bird species is present in the study area. Recently human activities and disturbance has become a great problem to the avifauna of this area. As an area for recreation on holidays, a huge number of people come to this garden for refreshment, picnic, shooting but unfortunately maximum of them are not aware about the biodiversity of this area and disturbances created by them. Disposal of waste materials such as plastics, polythenes, styrofoam food boxes, chips packets and other garbage in aquatic and terrestrial habitats, sound pollution, plastic pollution is becoming a great concern for the bird species in the study area. Re-construction of water body, construction work and development activities in 2018 and 2019 is probably one of the major cause of low diversity of birds in respected years. Proper planning and management for the bird species is emergence beside plants with strict maintenance.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eConflict of interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no relevant financial or nonfinancial interests to disclose.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe express our gratitude to the authority of National Botanical Garden and forest department for helping and giving us permission for field work in the study area. We are also grateful to Md.Tanvir Mia, Shofiul Alam and number of volunteers for their participation during field visit.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eThis study was totally self-funded.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical Approval:\u0026nbsp;\u003c/strong\u003eNot applicable for this research, because not any individual was collected for the clinical test or trial.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u0026nbsp;\u003c/strong\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials:\u0026nbsp;\u003c/strong\u003eData will be available upon the request of the respective person.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eBanglapedia (2021) National Botanical Garden, Mirpur, Dhaka, Bangladesh. Banglapedia, National encyclopedia of Bangladesh https://en.banglapedia.org/index.php/Botanical_ Garden\u003c/li\u003e\n\u003cli\u003eBibby CJ, Burgess ND, Hill DA, Hillis DM, Mustoe S (2000) \u003cem\u003eBird census techniques\u003c/em\u003e. Elsevier.\u003c/li\u003e\n\u003cli\u003eBray JR and JT Curtis (1957) An ordination of the upland forest communities of southern Wisconsin. Ecol Monogr 27: 325\u0026ndash;349.\u003c/li\u003e\n\u003cli\u003eChishty N, Parveen R, Choudhary N L, Patel P, Kumawat P (2021) Food and Feeding Behavior of Red Vented Bulbul (Pycnonotus cafer) and Role in Seed Dispersal at Urban Area, Udaipur, Rajasthan, India. Asian J Biol Life Sci 10: 41\u0026ndash;46.\u003c/li\u003e\n\u003cli\u003eChowdhury S, Shahriar SA, B\u0026ouml;hm M, Jain A et al., (2021) Urban green spaces in Dhaka, Bangladesh, harbour nearly half the country\u0026rsquo;s butterfly diversity. J Urban Ecol 7: 1\u0026ndash;11.\u003c/li\u003e\n\u003cli\u003eEgwumah FA, Egwumah PO, Edet DI (2017) Paramount roles of wild birds as bioindicators of contamination. Int J Avian \u0026amp; Wildlife Biol 2: 1\u0026ndash;7.\u003c/li\u003e\n\u003cli\u003eEmrose A, Shome AR, Alam MM, Rabbe MF, Hawladar N Jaman, MF (2024) Northwestern transboundary area of Bangladesh: a key to sustaining a quarter of the country\u0026rsquo;s avian species. \u003cem\u003eOrnithol Res\u003c/em\u003e 32: 23\u0026ndash;32.\u003c/li\u003e\n\u003cli\u003eFils EMB, Anong AGBA, Tsala B, Guiek\u0026eacute; BB, Tsala DE, Fotso AK (2014) Diversity of bats of the Far North Region of Cameroon\u0026ndash;with two frst records for the country. Biodiv 15: 16\u0026ndash;22.\u003c/li\u003e\n\u003cli\u003eGrimmett R, Thompson P, Inskipp T (2021) \u003cem\u003eField Guide to the Birds of Bangladesh\u003c/em\u003e. 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Urban Green 77: 127756. \u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Bird, Urban, Community, Ecology, Habitat heterogeneity, Season, Conservation and Protected area","lastPublishedDoi":"10.21203/rs.3.rs-4733401/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4733401/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eNatural habitats were converted to human-modified landscape as a result of urbanizations in metropolitan areas which resulting in alteration of avian species composition. Analyzing bird habitat preferences and seasonal dynamics can help us better understand how they adapt to changing environments. We used the point count approach at Bangladesh's National Botanical Garden to gain a thorough picture of how a protected landscape playing role in avian biodiversity conservation in a mega-populated, highly polluted city with experienced with extremely modified natural habitat. Along with impacts of habitat heterogeneity and temporal changes on avian community composition was also detected for this three years long survey. Observations based on habitat and seasonal trends revealed a diverse avifauna with 133 bird species (about 20 percent of the country's avifauna) and 5931 individuals belonging to 16 orders and 46 families. Richness and abundance of birds varied significantly among the habitats and season types. The highest richness, abundance and diversity indices was calculated for tree (H\u0026thinsp;=\u0026thinsp;3.645, D\u0026thinsp;=\u0026thinsp;0.966) and the pair-wise ANOVA test for habitats was significant only for tree. Red-vented Bulbul \u003cem\u003ePycnonotus cafer\u003c/em\u003e ranked as the most abundant species and we found seven generalist species based on their habitat preferences. Bird assemblages were richer in winter showed significant variation in pair-wise ANOVA test. Although bird diversity was found maximum in winter (H\u0026thinsp;=\u0026thinsp;3.935, D\u0026thinsp;=\u0026thinsp;0.976), evenness was calculated the highest for rainy season (E\u0026thinsp;=\u0026thinsp;0.711\u003cb\u003e)\u003c/b\u003e. The findings of this study demonstrated that bird variety is strongly linked to their various habitats and seasons. Avifaunal persistence was aided by habitat heterogeneity, which provided optimal foraging, roosting, and breeding options for birds. Diverse type of native plantations habitat and wetlands with natural habitat could aid in conservation of avian communities in urban area. The diversity of bird species revealed the ecosystems' intactness and ecological soundness. This finding provides the foundation for a long-term study of the bird-habitat connection and seasonal fluctuations.\u003c/p\u003e","manuscriptTitle":"Protected Landscape with Natural Habitat inside Urban Area Could Conserve Avifauna Biodiversity: A Long-term Study from an Overpopulated Subtropical Megacity","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-08-21 10:07:05","doi":"10.21203/rs.3.rs-4733401/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"a5023533-0094-4d1b-82e1-037ccea54374","owner":[],"postedDate":"August 21st, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-05-06T02:08:35+00:00","versionOfRecord":[],"versionCreatedAt":"2024-08-21 10:07:05","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4733401","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4733401","identity":"rs-4733401","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}