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In human-dominated landscapes, roads are known to negatively influence birds causing decline in species richness, as well as reduction in the number of avian species. However, linear stretches of green spaces formed by roadside plantations in urban streetscapes can support diverse avian communities. In spite of being an integral habitat feature of urban areas, there is a clear paucity of studies on avian diversity in urban streetscapes. The present study was carried out in Kolkata, where data on avian species richness and abundance was collected from 16 randomly placed belt transects (replicates), each of 500 m length and 20 m width, on different major roads throughout the study area keeping a minimum gap of 200 m between adjacent transects to avoid data overlapping. Each of these transects were traversed on foot twice in a month from January to March 2017 during days with calm weather conditions. We recorded 31 species of birds belonging to 8 orders and 19 families, of which maximum species belonged to the order Passeriformes (13 species). We found that both abundance and species richness of birds in transects with higher number of trees (78±4.1 individuals and 19.55±1.703 species of birds) were significantly higher than transects with fewer trees (53.74±2.5 individuals and 9.5±0.789 species of birds). Amongst various habitat features along these streetscapes, the total number of trees positively influenced both species richness (GLMM: F1, 90=14.485, P1, 90=8.081, P

The fishing cat (Prionailurus viverrinus) is a medium-sized felid, which uses various habitats including areas adjoining wetlands. This species is listed as ‘vulnerable’ in the IUCN Red List 2016, ...

Indian flying fox Pteropus giganteus (Brunnich, 1782) is one of the largest fruit bats (Pteropodidae) in the world. However, studies on seasonal variations and influence of weather parameters on diurnal roosting of this species in urban areas are almost non-existent. We carried out this study in a major urban landscape of India to determine which weather parameters influence diurnal roosting behaviours of Indian flying fox. Behavioural data was assessed through scan sampling method. Sleeping, thermoregulatory, locomotion and communicative behaviour, all of which varied significantly, showing highest incidences of sleeping followed by thermoregulatory, locomotion and communicative behaviours. Sleeping was negatively related with thermoregulatory, locomotion and communicative behaviours; thermoregulatory behaviour was positively related with locomotion and locomotion with communicative behaviour. Except sleeping, all other behaviours were positively related to temperature and were higher in summer than winter. Cloud cover negatively influenced sleeping and positively influenced thermoregulatory and locomotion behaviour; humidity negatively influenced thermoregulatory behaviour and rainfall negatively influenced locomotion behaviour of Indian flying foxes. Our findings might be useful for conservation of diurnal roosting sites of fruit bats in many urban landscapes in the recent scenario of changing climate and rapid urbanization throughout the globe.

Documentation of avian assemblages in different ecosystems is very important from environmental monitoring perspective. We assessed the species richness and foraging guilds of birds in different habitats of a suburban area in lower Gangetic plains (Bongaon, West Bengal, India) where no such studies have been done so far. Overall, 119 species of birds were recorded during the study period (June 2015 – May 2016) for the entire study area. Maximum species belonged to order Passeriformes (52 species). Based on species richness of birds, the dendrogram revealed two distinct clusters of habitats, one containing perennial wetland, riverine mixed vegetation and seasonal wetland, and the other with residential area and plantation forest. Generalized linear model (GLM) with negative binomial distribution and log-link revealed that species richness of birds significantly varied between different habitats and seasons. Agglomerative Hierarchical Clustering using avian species richness revealed that the habitats associated with water bodies fall under separate cluster and had higher species richness than the cluster containing habitats without water bodies. Maximum bird species was noticed in perennial wetland followed by riverine mixed vegetation, seasonal wetland, residential area and plantation forest. Richness of insectivores was highest in perennial wetland and riverine mixed vegetation, number of carnivorous species was maximum in seasonal wetlands, while omnivores showed the highest richness in residential area and plantation forests. This area supports two near threatened (NT) species namely black-headed ibis (Threskiornis melanocephalus) and Alexandrine parakeet (Psittacula eupatria). Our study is the first effort towards assessment of habitat-wise species richness of birds in this suburban area which supports good number of avifauna. Findings of the present study could serve as an important baseline to assess the impact of urbanization and habitat change on avian species richness in this suburban landscape, and might also be useful in adopting sustainable and bird-friendly management plan for this area.

Avian communities are very good indicators of any ecosystem. Despite the alarming consequences of rapid urbanization, studies of avian diversity in the human-dominated landscapes of India are very few. Therefore, we studied the avian assemblage of Bongaon in southern West Bengal, India, a suburban area whose avifauna has thus far remained undocumented. Bird surveys were carried out from June 2015 to May 2016, following the fixed-radius (25 m) point count method together with opportunistic observations. We recorded 119 avian species belonging to 53 families. Ardeidae was the most diverse avian family in the study area (RDi value = 5.882). Among the recorded avifauna, 89 species were resident, 26 species were winter visitors, three species were summer visitors, and one species was a passage migrant. Species richness of the resident and passage migrant species did not vary seasonally, while the winter and summer visitors displayed significant seasonal variation. In this suburban area, the species richness of feeding guilds varied significantly. Most birds were insectivorous (41.2%), followed by carnivorous (24.4%), omnivorous (18.5%), granivorous (7.6%), frugivorous (3.4%), nectarivorous (3.4%) and herbivorous species (1.7%). Maximum species richness was recorded in November and minimum species richness in July. Black-headed Ibis Threskiornis melanocephalus and Alexandrine Parakeet Psittacula eupatria are two near-threatened species found in this region. Interestingly, six species having a globally declining trend are still very common in the study area. Long-term studies are required to monitor any change in the avian communities of this suburban landscape resulting from urbanization.

Monitoring of avian community composition in different landscapes are being emphasized from environmental monitoring perspective. Okhla bird sanctuary is an important bird area and has widest flood plains along the stretch of river Yamuna flowing through National Capital Region, India. At the same time, this sanctuary is under tremendous pressure particularly due to encroachment, unsustainable harvesting and pollution. Present study was carried out in Okhla bird sanctuary from July 2004 to June 2005 to assess the species composition and richness of the avifaunal community along with their seasonal variation. A total of 126 species belonging to 18 orders and 44 families were recorded. The avian species richness was highest for the order Passeriformes followed by Charadriformes, Anseriformes, Pelicaniformes and others. Anatidae was the most diverse avian family in the study area. Species richness of avifauna was highest in January (83 species) and least during July (37 species). This wetland supports good number of resident (86 species) and migratory birds (40 species). Most avian species (41.27%) were found to be wetland-dependent followed by wetland-associated (34.13%) and terrestrial (24.6%) birds. Kruskal–Wallis test revealed significant variation in the number of migratory and wetland-dependent species in different seasons. This study emphasize the importance of Okhla bird sanctuary for resident and migratory, as well as, terrestrial, wetland-associated and wetland dependent birds and thus contribute towards the existing knowledge of the seasonal pattern avifaunal composition of this wetland. Long-term monitoring of avifaunal composition over the years is an excellent means to assess the health of this waterbody and thus might be useful to foster its sustainable improvement.

Research on raptors in general in India is scanty, and it is practically non-existent on black kites (Milvus migrans govinda) which are the major scavenging raptor in many urban areas. The aim of this study was to analyse the seasonal abundance and roosting behaviour of black kites in an urban metropolis. Data on the abundance and behaviour of roosting black kites in this setting were collected using evening roost counts and ad-libitum sampling, respectively. Analysis was performed using separate generalized linear models considering roosting kite abundance, number of black kites arriving to roost and number of black kites showing pre-roosting display as response variables, respectively. We found that black kites roosted communally and that their number varied in different years and seasons, with the abundance highest in the summer and lowest during the winter. Pre-roosting displays also varied seasonally, being highest during the monsoon and at a minimum in the winter. In our urban setting, black kites arrived at the roosting sites mostly after sunset, and their arrival was influenced by sunset time, temperature, relative humidity and season. Some behavioural aspects of black kites within the roosts were also documented. This is the first quantitative assessment of roosting black kite abundance in Kolkata, India, and our data provide insight on the roosting behaviour of these birds relative to various environmental parameters.

Large numbers of black kites (Milvus migrans govinda) forage with house crows (Corvus splendens) at garbage dumps in many Indian cities. Such aggregation of many individuals results in aggressiveness where adoption of a suitable behavioral approach is crucial. We studied foraging behavior of black kites in dumping sites adjoining two major corporation markets of Kolkata, India. Black kites used four different foraging tactics which varied and significantly influenced foraging attempts and their success rates. Kleptoparasitism was significantly higher than autonomous foraging events; interspecific kleptoparasitism was highest in occurrence with a low success rate, while ‘autonomous-ground’ was least adopted but had the highest success rate.