Showing 28 results for Diversity
Ayan Mondal, Nilanjan Das, Sudipto Mandal,
Volume 4, Issue 1 (3-2022)
Abstract
The domestication of rice (Oryza sativa L.) has a rich history with its diversification from wild progenitors based on genetic differences. For human benefit, natural environments have been agriculturally modified. Concurrently, the biodiversity of natural or wild environments is greatly affected. Here, a comparison has been made between the biodiversity associated with wild-type rice and domesticated rice fields. Species were categorized into broad groups, i.e. Arthropoda (Arth), Other Invertebrate (OInv), Vertebrate (Vert), Algae (Alg), Fungi (Fng), Pteridophyta (Ptrd), and Higher Plant (HPlan). Physico-chemical factors including water depth (WD), water pH (pH), temperature (T), total hardness (TH), dissolved organic carbon (DOC), turbidity (Turb), and dissolved oxygen (DO) were measured directly in the field. Statistical analysis such as Student’s t-test, Kolmogorov-Smirnov test for equal distributions, tests for dominance and multiple indices including Simpson, Shannon, and Evenness were used to assess the biodiversity. Furthermore, Principal Component Analysis (PCA) and Multivariate Analysis of Variance (MANOVA) were used for community comparisons, and SIMPER analysis was used to assess dissimilarity between taxa. The Artificial Neural Network model (ANN) was applied to assess the relative importance of factors governing the system. The present study showed the assemblage of species in the wild along with domestication. The vertebrate species number was well correlated with all the other biotic groups indicating a bottom-up controlling pattern in the rice field ecosystem. The ANN analysis showed that of the environmental factors examined, WD played the most important role followed by pH, T, DOC, and DO as the next most influential factors in distinguishing wild and domesticated rice field ecosystems. SIMPER analysis demonstrated that arthropods were a major contributor to dissimilarity. Collectively our results showed that the domestication of rice led to a decline in biodiversity.
Sagar Adhurya, Debayan Gayen, Suvendu Das, Santanu Ray,
Volume 4, Issue 1 (3-2022)
Abstract
The focus of the present study was (i) to develop a complete checklist, (ii) to find the seasonal variation of waterbird diversity, and (iii) to assess the population trends of different waterbirds at Lake-2 of the Ballavpur Wildlife Sanctuary (BWLS), Birbhum District, West Bengal, India. The study was carried out from January 2018 to November 2019. All waterbirds spanning in the freshwater lake were counted with field binoculars and digital cameras. The bird count data were used to calculate different biodiversity indices (such as Shannon-Weiner diversity index, Simpson’s Diversity Index etc.). Further, we assessed the population trends of different waterbirds with the data available from eBird. A total of 32 waterbird species belonging to 27 genera, 9 families and 8 orders were recorded during the present study. Dendrocygna javanica (Horsfield) was found to be the most dominant species throughout the year. Maximum richness and abundance were recorded during the winter months (December to February), whereas the highest species diversity was recorded during the monsoon months (March to June). The present study further establishes that both the richness and abundance of the waterbirds at BWLS have increased as compared to the past data. However, various species of wading waterbirds that were recorded previously were not observed during the present study. Moreover, the population trend analysis revealed a strong decline in the population of Mareca strepera (Linnaeus) and a moderate increase in the population of Ardeola grayii (Sykes). Thus, the present study concludes that BWLS supports high waterbird diversity irrespective of its small area.
Subhajit Roy, Aniruddha Singhamahapatra, Amar Kumar Nayak,
Volume 4, Issue 2 (6-2022)
Abstract
The diversity and heterogeneity of Odonata was studied at 10 sites located across almost all parts of the Bankura district (except northwestern and northeastern boundary regions), in the state of West Bengal, India from July 2015 to June 2022. Analysis of variance and rarefaction was performed to study the β-diversity and compare the taxa abundance at the sites to understand the heterogeneity of Odonata observations. The seasonality of the species and their site-wise distribution were also studied. A total of 74 odonate species belonging to eight families, represented by 46 genera were recorded. The study adds 17 species to the known Odonata fauna of Bankura district, including the addition of Microgomphus torquatus (Selys) to the fauna of West Bengal. It also confirms the addition of Ictinogomphus kishori to the known Odonata fauna of West Bengal, which has been confused with and misidentified as Ictinogomphus distinctus for long, the latter being described from the state of West Bengal and is also found in the region adjacent to the study area. Most recorded odonates belonged to the family Libellulidae (29 species), followed by Coenagrionidae (19 species), Gomphidae (nine species), Platycnenididae (six species), Aeshnidae (five species), Macromiidae (three species), Lestidae (two species), and Chlorocyphidae (one species). Species diversity and abundance assessments are essential for conserving the habitats of the restricted and endemic (to peninsular India) species.
Rajendra Singh, Garima Singh,
Volume 4, Issue 2 (6-2022)
Abstract
In this review, an updated checklist of spider diversity in Rajasthan, India is presented. A total of 173 spider species from 90 genera belonging to 25 families are listed with records/descriptions originating from only 20 out of 33 districts of Rajasthan. A total of 74 taxa recorded from various districts of Rajasthan were identified only up to generic level. The maximum number of spider species were recorded from Jodhpur district (72 species), followed by Ajmer (69 species), Bharatpur (66 species), Pali (63 species), Jaipur (58 species), Dholpur and Karauli (38 species each), Jhunjhunu and Sikar (31 species each), Sri Ganga Nagar (26 species), Hanumangarh (25 species), and Jaisalmer (26 species). A fewer number of species are known from other districts. Thus far, no faunal surveys of spiders have been conducted in 13 districts of Rajasthan. Most of the national parks and wildlife sanctuaries, forest areas, agricultural fields, human dwellings, etc. within the state still await intensive and extensive surveys to record the spider fauna.
Erica Demilio, Denis V. Tumanov, Colin Lawton, Reinhardt Møbjerg Kristensen, Jesper Guldberg Hansen,
Volume 4, Issue 2 (6-2022)
Abstract
Two new heterotardigrade (Tardigrada) species, Bryodelphax pucapetricolus sp. nov. and Bryodelphax wallacearthuri sp. nov., are described from moss associated with limestone pavement in the Republic of Ireland. The species description process for these two taxa initiated a more detailed exploration of several morphological characters of importance in Bryodelphax Thulin including cuticular sculpture elements and ventral plate morphology. Division of the third dorsal median plate in the context of the genera Bryochoerus Marcus and Bryodelphax is further discussed. We recommend minor emendations to the generic diagnoses of Bryochoerus and Bryodelphax. Also, we emend the species diagnoses of Bryodelphax aaseae Kristensen, Michalczyk and Kaczmarek and Bryodelphax parvuspolaris Kaczmarek, Zawierucha, Smykla and Michalczyk, record the genus Parechiniscus Cuénot from the Republic of Ireland for the first time, and make suggestions relevant to the taxonomy of limnoterrestrial heterotardigrades.
Azadeh Rezaei, Hoda Khaledi, Ahmad Savari, Babak Dostshenas, Hossein Mohammad Asgari, Rezvan Attari,
Volume 4, Issue 3 (9-2022)
Abstract
Macrobenthos play an important role in aquatic ecosystems because they mineralize, promote, and mix the oxygen flux into the sediment, which recycles the organic matter. Sampling of macrobenthos populations for this study was carried out in the supratidal, mid tidal, low tidal, and subtidal regions of the Dayyer, Ouli, and Kangan stations in the Persian Gulf during both cold and warm seasons. Water parameters such as the temperature, salinity, pH, turbidity, and electrical conductivity were assessed, and were indicative of moderate water quality. Representatives of a total of 31 taxonomic families were identified during both seasons, of which 59 were identified to genus and species. The highest average number of species was observed in the low tidal region of Kangan in the warm season at 16.6 ± 1.2 species, and the lowest number was observed in the supratidal regions of Ouli and Kangan in the cold season at 6.6±2 species. The species diversity, as calculated using the Shannon–Wiener Index (H’), showed a significant difference between sampling seasons and sampling stations, as well as pollution level at the beaches. The species diversity index in Ouli, Dayyer, and Kangan stations also differed between the seasons. In both seasons, the Kangan station showed the highest species diversity while the Dayyer station showed the lowest. These results reveal a rich species diversity of macrobenthos and good water quality at the three beaches in the Persian Gulf. Re-assessment of species diversity during an environmental impact assessment prior to urban development should be further conducted to ensure that the
community is not significantly affected and the ecosystem remains intact.
Vasantkumar M. Rabari, Arzoo Malik, Nishith Dharaiya,
Volume 4, Issue 3 (9-2022)
Abstract
Knowledge of the occurrence and distribution of terrestrial mammals is imperative in the design of conservation strategies in protected areas. There is a lack of information available on the occurrence and abundance of wild mammals in the Balaram-Ambaji Wildlife Sanctuary, Gujarat of India. Thus, the present study was carried out to understand the relative abundance of the wild mammalian species in the Balaram-Ambaji Wildlife Sanctuary via camera trapping. We used day/night camera traps to record the presence of diurnal and nocturnal mammals in the Balaram-Ambaji Wildlife Sanctuary. We plotted 11 cameras near water bodies for 20 days from 6 January 2020 to 26 January 2020. A total of 268 photographs of wild animals were captured. Among the photos 13 wild mammalian species were identified, including the Rusty-spotted cat Prionailurus rubiginosus (I. Geoffroy Saint-Hilaire), which is reported for the first time in this area. The Relative Abundance Index (RAI) of each identified species was calculated to understand the species richness, providing baseline data for species occupancy.
Shipra Khanduri, Vedagiri Thirumurugan, Chandravilasam Sreedharan Nair Vishnu, Chinnasamy Ramesh, Abhijit Das, Gautam Talukdar,
Volume 4, Issue 4 (12-2022)
Abstract
A comprehensive record of reptiles found in the Moyar River Valley Landscape (MRVL) is presented in this manuscript. The observations did not adhere to standardized survey methods, and are based on opportunistic encounters during our vegetation survey in different habitats of the MRVL between December 2017 and December 2019. A total of 135 live individuals and 31 road-killed specimens, representing 37 species of reptiles were recorded of which two species are Vulnerable, 13 are Least Concern and 22 species are Not Evaluated in accordance with the criteria of the IUCN Red List of Threatened Species. The recorded species belonged to six families of lizards (Agamidae, Chamaeleonidae, Gekkonidae, Lacertidae, Scincidae, and Varanidae), six families of snakes (Colubridae, Elapidae, Erycidae, Pythonidae, Typhlopidae, and Viperidae), two families of chelonians (Geoemydidae, and Testudinidae), and one family of Crocodylia (Crocodylidae,). The road-killed specimens were recorded between the year 2018 and 2020 and come under Indian Wildlife Protection Act, 1972. Though the present work did not follow a specific survey method, the contribution provides baseline information on the reptile diversity of the MRVL and presents interesting findings from the Sathyamangalam and Mudumalai Tiger Reserves in north-western Tamil Nadu, India.
Brian Sabanal, Marion John Michael Achondo, Pedro Alviola Iv, Lief Erikson Gamalo, Mae Responte,
Volume 4, Issue 4 (12-2022)
Abstract
In addition to protected landscapes, anthropic land covers (ALCs) can also harbor spiders in human-modified landscapes (HMLs). This study determined the diversity of spiders in seven different ALCs within the University of the Philippines Mindanao campus in order to identify ALCs with the highest priority for spider conservation. Direct sampling methods were employed to collect specimens within 2,000 m2 belt transects. A total of 364 spider individuals belonging to 69 morphospecies from 40 genera and 13 families were documented. Highest species richness was observed from the family Araneidae. Nephila pilipes Fabricius (Araneidae) and Heteropoda venatoria Linnaeus (Sparassidae) were found across sampling sites. Among the ALCs, site 5OGSF (old- growth and secondary forest) had the highest species richness (q0 (26)) while site 7AF (agroforest) had the highest species diversity (q1 (17.16); q2 (13.83)). Site 3CTP (cacao tree plantation) was consistently the least species-rich (q0 (10)) and least diverse (q1 (6.92); q2 (5.54)). The different vegetation density and structural complexity of ALCs on the campus support spider communities in which the highest species richness and diversity were observed in the secondary forest and agroforest, respectively. This paper highlights that spider communities have varying levels of diversity in different small-scale ALCs.
Hoda Khaledi,
Volume 4, Issue 4 (12-2022)
Abstract
Benthic macrofauna has a pivotal role in the energy flow and material cycles of marine ecosystems. Abiotic and biotic factors determine the presence and distribution of benthic macrofauna. The present study investigated possible relationships between benthic macrofauna and natural abiotic factors along the coastal region of the Gulf of Oman, including the north of Chabahar Bay, Konarak, and Tis. This was achieved through survey of the supra-littoral and intertidal zones at low tide, during the cold and warm seasons. In each zone, nine transects were sampled at random using quadrats. Then, sediment characteristics and macrofaunal abundance were determined. Mollusks and echinoderms had the highest and the lowest species richness, respectively. The average values for the Shannon–Wiener index of the transects at Tis, north of Chabahar Bay, and Konarak were 3.22, 3.28, and 3.20 in the warm season, respectively, while the index reached 3.29, 3.47, and 3.17 in the winter. Regardless of seasonality, the level of biodiversity was at a maximum in the northern part of Chabahar Bay, and Konarak showed the minimum biodiversity. The results of multi-linear regression analysis proposed that non-biological factors are suitable proxies for predicting the levels of species density in the study regions (R2= 0.72, F(6,71) = 2.25, p< 0.05).
Usha J. Zala, Jatin V. Raval, Romanch S. Nimavat, Namrata K. Hun,
Volume 4, Issue 4 (12-2022)
Abstract
The present study was conducted to study avifaunal diversity of Girnar Wildlife Sanctuary, Junagadh, Gujarat, India. This study was carried out from August 2020 to August 2022. Data collection was done using a point count method and visual encounter method, with opportunistic sighting also included. A total of 276 species of birds belonging to 70 families and 21 orders were recorded from Girnar Wildlife Sanctuary. In the present study out of 70 families, Accipitridae and Muscicapidae were the most dominant families with 24 species each. As per the IUCN status, 261 species are Least Concern, three species are Critically Endangered, one species is Endangered, eight species are Near Threatened and three are Vulnerable. Out of seven foraging guilds, species of birds classified as Insectivores were dominant. The results obtained provide baseline information on the avifaunal diversity of Girnar Wildlife Sanctuary, which will help in further conservation implications.
Adarsha Mukherjee, Arjun Kumar, Supriya Mahato, Supriya Samanta,
Volume 5, Issue 1 (3-2023)
Abstract
To understand and update the account of the butterfly diversity in Ajodhya Hills, Purulia, West Bengal, India a study was carried out in two consecutive years from January 2020 to December 2021 with photographic documentation. A total of 143 butterflies from 6 families, 19 subfamilies and 95 genera were recorded. The highest richness was found in the families Nymphalidae with 45 species and Lycaenidae with 44 species, whereas Riodinidae had the lowest richness with only 1 species recorded. This study also reports the addition of one species, Black Angle Tapena thwaitesi (Moore), to the state butterfly fauna of West Bengal, as well as the addition of one species, Common Orange Awlet Burara jaina (Moore), to the butterfly fauna of southern West Bengal. In addition, three species, Plain Banded Awl Hasora vitta (Butler), Malabar Spotted Flat Celaenorrhinus ambareesa (Moore) and Common Acacia Blue Surendra quercetorum (Moore), were recorded with the first photographic documentation from southern West Bengal representing the rediscovery of Malabar Spotted Flat after 124 years from the Chotanagpur Plateau of West Bengal. The present study updates knowledge of the butterfly diversity of Ajodhya Hills and discusses the threats and conservation of the area, which may help in threat prevention, developing effective conservation strategies and to build awareness among the local people and government authorities to save the wildlife of Ajodhya Hills and its habitats.
Dhanapal Sangavi, Padur Sankaranarayanan Anisha, Govindharaj Vinothini, Parthasarathy Thiruchenthil Nathan,
Volume 5, Issue 1 (3-2023)
Abstract
A detailed investigation of the spider diversity in Salem district, Tamil Nadu was carried out across different habitats for a period of five years. A total of 184 spider species belonging to 97 genera in 29 families were recorded, which represented nearly 10% of Indian and 65% of Tamil Nadu spider diversity. Among them 25 spider species are endemic to India. From the 29 families, the 3 most abundant families based on number of specimens sampled were Lycosidae (21%), Araneidae (18%), and Eresidae (17%), constituting 56% of the spider species. Simpson diversity indices ranged between 0.88 to 0.30 for all the studied habitats. The species richness was highest in bamboo fields (2.78), and the lowest was observed in grasslands (0.76). The highest abundance of spider species was observed in the sugarcane fields (0.83), followed by the grasslands (0.57) and paddy fields (0.53). Further, these spiders were categorized into nine types based on their foraging guilds. Among them, the highest species richness was observed in foliage runners. A maximum of nine spider guilds were observed in the shrub ecosystem. Natural ecosystems such as shrublands, treescapes, and grasslands had higher spider diversity than altered agricultural and domestic ecosystems. This is the first report on spider diversity in Salem District, Tamil Nadu revealing the varying spider diversity along with their guild types across different habitats.
Kalyan Mukherjee, Ayan Mondal,
Volume 5, Issue 2 (6-2023)
Abstract
In this paper, we present a preliminary checklist of butterfly larval host plants from the Bankura and Purulia districts, which are a part of the Chotanagpur Plateau of West Bengal, India. The authors found 223 plant species from 52 plant families, which were used as larval hosts by 124 butterfly species. In terms of the use of plant families and species, we discovered a strong positive association between Nymphalidae and Hesperiidae and between Lycaenidae and Pieridae. According to our two-way ANOVA findings, there are notable variations in plant usage among butterfly families, which were elaborately discussed using hierarchical classical clustering. Most of the plant species utilized were from the Fabaceae and Poaceae families.
Khean Harvey S. Acuevas, Dave P. Buenavista,
Volume 5, Issue 3 (10-2023)
Abstract
The Center for Ecological Development and Recreation (CEDAR) is an ecotourism site comprised of natural and human-modified ecosystems in Bukidnon, Philippines. With very little existing research on the influence of human-modified ecosystems on amphibian assemblages in the Philippines, we designed this study to evaluate amphibian assemblages in CEDAR. Using a combination of transects sampling, active searching, and auditory samplings, amphibian samplings were conducted at three sites: a human-modified area, a dipterocarp forest, and the Dila River System. A total of 425 individuals of 18 species from 13 genera and 7 families were documented. The family Ceratobatrachidae was the most represented group, with four species. Out of 18 species, 14 (78%) were Philippine endemics, indicating a high rate of amphibian endemism at CEDAR. In terms of IUCN conservation status, 14 out of 18 species were classified as Least Concern and two as Near Threatened, while two have undetermined conservation status. The Shannon-Weiner and Gini-Simpsons Diversity values revealed that the Human-modified area had the highest diversity compared to the Dila River System and dipterocarp forest. Surprisingly, the human-modified area in CEDAR was found to be the habitat of many anuran species, in particular, a number of generalist species, whilst some specialist species were restricted to natural habitats like the dipterocarp forest and Dila River System. The high amphibian diversity in the human-modified area requires further field studies; hence, additional amphibian samplings are recommended. Long-term wildlife evaluation and monitoring should be carried-out in CEDAR to facilitate the conservation of amphibian populations and their natural habitats in this area.
Rajesh Lenka,
Volume 5, Issue 3 (10-2023)
Abstract
The present study was undertaken from November 2020 to October 2021 to understand the bird species diversity, and variation in their seasonality, near the National Thermal Power Corporation (NTPC) area of Talcher located in Angul district of Odisha state in India. The identified birds included 668 individuals of 90 species (including three near-threatened species) belonging to 18 orders, 41 families and 75 genera. As per the study, Passeriformes is found to be most dominant with 34 species (38% of total bird species). Considering the feeding guilds of birds, insectivore bird species were found in higher number (32 species) followed by carnivores (16 species), and then omnivores and frugivores (10 species each). It was found that the winter season was the most species rich (70 species, 328 individuals), and the monsoon season the least (43 species, 127 individuals). The Shannon-Wiener index (H'= 3.48) was also found to be high in winter season but the evenness index (E= 0.65) was found to be higher in monsoon season. The cluster analysis showed that the bird composition of the summer season strongly correlates with bird composition of the winter and monsoon seasons, but the bird composition of the monsoon season is not significantly correlated with bird composition of the winter season. The results from the study can act as the baseline for further research on birds in the Angul district of Odisha.
Laxmi Sagar, Dhan Bdr Gurung, Karma Wangchuk, Karma L. Wangmo, Rinchen Dorji, Tshering Zangmo, Rupesh Subedi,
Volume 5, Issue 4 (10-2023)
Abstract
Cyprinidae (Teleostei: Cypriniformes) is the predominate family among Bhutan's freshwater fishes, yet significant gaps exist in the knowledge of their diversity and assemblage. Cyprinids were sampled from 54 plots across four river basins (Aiechhu, Jaldakachhu, Mangdechhu, and Punatsangchhu) using systematic sampling at an interval of 5 km. A total of 850 individuals belonging to 22 species and 13 genera were recorded. Aiechhu had the highest diversity and evenness (H’= 1.66±0.28, J’= 0.95±0.03), followed by Punatsangchhu (H’= 1.58±0.34, J’= 0.94±0.04). Meanwhile, Jaldakachhu and Mangdechhu exhibited the lowest diversity and evenness (H’= 0.90±0.66, J’= 0.84±0.54 and H’= 0.54±0.70, J’= 0.38±0.49, respectively). There was a significant difference in diversity among river basins (χ2 (3)= 20.98, p < 0.001) with specific variation between Mangdechhu and Punatsangchhu (Z= 3.80, p= 0.00), Mangdechhu and Aiechhu (Z= 3.35, p= 0.01), and Jaldakachhu and Punatsangchhu (Z= 2.83, p= 0.03). Canonical correspondence analysis indicated that cyprinid assemblage was significantly correlated with environmental variables (r= 0.94, p= 0.001 in axis 1 and r= 0.82, p= 0.001 in axis 2) explaining 77% of variance. Axis 1 was positively correlated with temperature (r= 0.92), total dissolved solids (r= 0.53), conductivity (r= 0.51), and salinity (r= 0.39) and negatively correlated with elevation (r= −0.69). Axis 2 was negatively correlated with total hardness (r= −0.82) and dissolved oxygen (r= −0.65). Cluster analysis identified three clusters based on dominant species. Further studies exploring other river basins of Bhutan are needed to better understand the ecological dynamics of cyprinids in Bhutan.
Abdullah Atabey, Recep Karakaş,
Volume 6, Issue 1 (3-2024)
Abstract
Birds have a special importance in the exceptionally rich biodiversity of Türkiye; nevertheless, the ornithological importance of some parts of the country is inadequately known. The bird diversity of Mount Zülküf (MZ) was studied together with recommendations for conservation proposals. In total, 26 field surveys were conducted on MZ, which is located 6 km from Ergani district of Diyarbakır province, south-eastern Türkiye. During the field observations, transect line and point count methodologies were used, accompanied by the use of standard ornithological equipment, between April 2017 and April 2018. It was aimed at determining the seasonal status, breeding status, and threatened categories of bird species, together with suggesting conservation proposals. Within the scope of the studies conducted in the limited area over one year, 73 bird species, belonging to 25 families and nine orders were determined. Among the bird species identified, 19 are possible, 16 are probable, and 14 are certainly breeding species for the area; which means that 67% of them have breeding potential in the study area. Among the recorded bird species, there is one globally threatened species, while seven are threatened within Türkiye with many more least concern or data deficient species. Recording the bird diversity of the mountain, together with the existing cultural importance of the area in terms of religious tourism, will help to bring to light the ecotourism potential of the area, and could be used for monitoring the area for conservation plans. Raising awareness of the region's bird diversity, among the local people, will offer nature-based tourism opportunities via ornithology in the region.
Marina Armel À Mmira Akohogni, Evrard Kouopestchop Medjo, Boddis Tsiguia Zebaze, Alexia Kevine Noubissi Chiassa, Pamela Cynthia Mepa Tchiegang, Claudine Tekounegning Tiogué, Dorothy Engwali Fon,
Volume 6, Issue 1 (3-2024)
Abstract
This study was carried out between October 2020 and October 2021 with the aim of determining sustainable management options and nutrition for the domestication of Mormyridae fish species living in the Sanaga River in central Cameroon. For this purpose, 451 specimens collected from local fishermen were identified and grouped into four genera and seven species, constituting 20.84% Campylomormyrus phantasticus (Pellegrin), 5.32% Hippopotamyrus castor (Pappenheim), 24.61% Mormyrops anguilloides (Linnaeus), 18.63% Mormyrops caballus (Pellegrin), 4.66% Mormyrops zanclirostris (Günther, 1867), 15.52% Mormyrus rume (Valenciennes), and 10.42% Mormyrus tapirus (Pappenheim). Fish were measured, and parameters were obtained after dissection using intestinal morphometric characteristics and stomach content analysis methods. The emptiness coefficient varied from 0% (Hippopotamyrus castor and Mormyrops zanclirostris) to 26.66% (Mormyrus rume). The relative mass of the intestine was low in all studied species; the intestinal coefficient and the Zihler index of all these species are within the range of carnivorous species. Analysis of stomach contents revealed a broad food spectrum containing twelve categories of prey. Insects, macrophytes and larval insect shelters were the preferred foods of Mormyrops anguilloides, Mormyrops caballus and Mormyrops zanclirostris, while insect larvae and larval shelters were the preferred prey for other species. Site and season had little effect on the categories of prey consumed by these species.
. Joseliph Abin, Padayatty Davis Samson,
Volume 6, Issue 1 (3-2024)
Abstract
Identification and characterisation of urban habitats and ascertaining their species associations are essential for the conservation and management of biodiversity in urban landscapes. The study attempts to identify, describe and categorise potential urban habitats in Kochi city, Kerala, India, and to explore the association of bird faunal assemblages within each of the habitats. The study was conducted from June 2018 to May 2020. The Urban Habitat Categories were identified, described and categorised as per the Urban Habitats Biodiversity Assessment (UrHBA) procedure and a sample biotope map was prepared. The habitat association of bird species was determined from each of the identified Urban Habitat Category by evaluating the species composition of each habitat. Species sharing between the identified habitats was also examined. Critical habitats of conservation concern were identified, and their specific features were ascertained. A total of 38 Urban Habitat Categories were characterised from the landscape of Kochi City with 162 species of birds to be found associated within the urban habitats. The wide variety of urban habitats provide excellent dwellings for a large number of birds including several threatened and migratory species. Out of the five major urban habitat categories, most of the species utilise Sparsely vegetated - Life form categories. Among the 38 urban habitats, Forest phanerophytes supports greater numbers of bird species. Vegetation structure is an important factor that determines bird diversity of the urban habitats. Together with the well-vegetated habitats, sparsely vegetated, non-vegetated and artificial built habitats also significantly contribute to biodiversity of urban centres. The diverse urban habitats and the associated bird species identified from Kochi city emphasise that modified urban landscapes are equally potent as natural landscapes in upholding diverse life forms. The study highlights the necessity of maintaining habitat complexity in urban landscapes for sustainable conservation of urban biodiversity. The baseline data on urban habitats and their species association will serve as a planning tool for safeguarding the critical habitats.
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