Resident Bird Species Research Articles

Community Structure of Resident and Migratory Bird Species in Talabong Mangrove Forest, Bais City, Negros Oriental, Philippines

Mangrove forests throughout the world are recognized as stopover sites by many migratory birds – including waders – as they contain ample food resources such as invertebrates, fruits, and flowers that are beneficial to most birds. In connection, the Talabong Mangrove Forest located in Bais, Negros Oriental, Philippines is recognized as a wildlife sanctuary, but no recent data on birds could supplement this. Thus, this study aims to assess the distribution patterns of migratory and resident birds in the said site during the southward migration which encompasses both wet and dry seasons. Also, the investigation determines whether Talabong mangrove could function as a stopover site for migratory birds. To examine the community structure, the populations of resident and migratory bird species were assessed for species composition, diversity, density, and abundance in three sampling periods: pre-migration, migration, and post-migration. The line transects and point-count methods were employed with four transect lines laid out on the study site. Each line stretched a kilometer long with a 250-m interval with five points for point-counting and was visited on each sampling period. Points were marked for a consistent sampling. For each sampling period, results showed that the birds’ abundance, diversity, and density remained consistently high throughout each sampling. Specifically, the species composition and the number of resident birds did not seem to alter and remained high as well. On the other hand, migrants had an abrupt increase during migration sampling and decreased towards the end. But similarity analyses suggest species composition remained approximately similar for the migrants. The results showed that Talabong mangrove forest contained some migratory species – making it a decent stopover site, although not as many migrants as in other protected mangroves and wetlands in the Philippines. The resident birds occupying the site may also have served as cues for the migrants.

SPECIES DIVERSITY OF BIRDS OF PREY IN HADEJIA NGURU WETLANDS, NIGERIA

The study aimed to determine the distribution, diversity and abundance of birds of prey in Hadejia Nguru wetlands Nigeria, carried out in March to August, 2021, with a view to providing information in a bid to establish a baseline for conservation for this group of birds. The Hadejia-Nguru Wetlands (HNWs) is a Ramsar site and an Important Bird Area (IBA) being recognized nationally and internationally as an ecological area for resident, inter-African and Palearctic migrant bird species in sub-Sahara region, Nigeria. Transect line method was used for the bird survey. This involved moving slowly along the transect line and recording all birds seen and detected in and around the transect line. The survey was carried out for a period of six (6) months using transect line method and each site was surveyed twice every month during the study period. Bird observation was carried out twice daily; morning between 6:00 to 10:00 a.m. and evening between 4:00 to 6:30p.m by walking slowly along the transect line. Birds were counted as birds seen and birds inflight were also counted. Richness index (RI) and t-test were used for data analysis. The total number of birds was calculated as the number of birds seen plus the number of birds heard. Transect line survey method detected a total of 1,562 individual birds of prey that belong to twenty four (24) species of 2 families. Accipitridae with 20 species is the richest family in species number and Falconidae with

Resident bird species track inter-annual variation in spring phenology better than long-distance migrants in a subalpine habitat

The ability to track variation in climate is important for species to persist in a given environment. Lack of responses to both long-term changes and inter-annual variation in climate parameters can result in reduced fitness and population decline. Furthermore, migration strategy can influence the ability to track climatic variation due to the potential to use reliable environmental cues. Here, we studied the temporal relationship between birch leafing and onset of breeding for three bird species with contrasting migration strategies over a 20-year period in a subalpine habitat in Central Norway. We found no temporal change in birch leafing date or breeding onset for the three bird species over the study period. However, we found a statistically significant difference in the ability to track inter-annual variation in birch leafing date between the resident and two long-distance migratory species. The resident great tit Parus major was more capable of initiating egg laying in closer association to variation in birch leafing in early springs, than the long-distance migratory European pied flycatcher Ficedula hypoleuca and common redstart Phoenicurus phoenicurus. Long-distance migrants seem to have been constrained by arrival date or time from arrival to entering the breeding areas, in contrast to resident birds, which might be better able track early initiation of spring in breeding areas by adjusting egg laying date. Our findings highlight the importance of not solely studying directional long-term climatic change, but also pay attention to inter-annual variation.

Diurnal activity patterns, habitat use and foraging habits of Egyptian goose (Alopochena egyptiacus Linnaeus, 1766) in the Boyo wetland, southern Ethiopia

Egyptian goose (Alopochena egyptiacus) is a resident bird species in Africa South of the Sahara occurring throughout the entire Nile Valley. Despite the wide distribution, the available information on its behavioral ecology is limited in Ethiopia. A study on the activity patterns, habitat use and foraging habits of Egyptian goose was carried out in and around Boyo wetland, Ethiopia, during the dry and wet seasons. Scan sampling method was used to study the activity patterns and habitat use of Egyptian goose in grassland, mudflat and shallow water habitats of the wetland. The feeding behavior of Egyptian goose was also observed in the surrounding farmland habitats using scan sampling method. Generally, Egyptian geese spent most of their time resting (39.81%) followed by foraging (32.64%). They spent 10.43% of their time in comfort movement preening or stretching. The rest of their time was allocated for locomotion (6.63%), vigilance (5.75%), and social behavior (1.59%), and other activities (2.86%). Most of the birds were engaged in foraging activity in the morning (07:00-9:00 h) and afternoon (16:00 - 18:00 h) hours both during the wet and dry seasons. About 39% of Egyptian geese were scanned in mudflat, 31.5% in grassland, and 30.05% in shallow water habitats engaged in different activities. Most individuals used the grassland habitat for foraging during the dry (59.5%) and wet (74%) seasons, while they used shallow water and mudflat habitats for resting both during the wet and dry seasons seasons. The birds were observed foraging mainly grass during the dry (93.62%) and wet (59.52%) seasons. The Egyptian geese show diurnal activity pattern with feeding peaks in early morning and late afternoon hours as is observed in many other avian taxa. The Boyo wetland is also as an important foraging ground for this species and other birds in the area. Further ecological studies on the species and impact of human activities on the Boyo wetland should be conducted for the conservation of the avifauna.

Conservation of avian diet specialization is complex and a challenging task for developing countries

Morelli et al. (2021) have highlighted that avian species with specialized diets are more prone to extinction, as information regarding their ecological requirements and other aspects of species’ biology is generally limited, and thus, these characteristics need to be studied in greater depth. They argue that the availability of such information would potentially encourage policy makers/managers to include aspects of dietary specialization alongside other normally considered metrics when designating more PAs. However, although we are in full agreement with the findings of this study, we have particular doubts as to whether researchers in developing countries are endowed with sufficient funds to even contemplate initiating studies on the ecological requirements of threatened species. In developing countries hosting threatened species, funds are generally allocated to surveys conducted to assess the status (presence/absence) of these species. Furthermore, given the high costs of conducting research, we are of the opinion that researchers in these countries are provided with fewer funding opportunities (Helden, 2012), particularly with respect to the study of those species for which numbers are extremely low, and thus are highly unlikely to be encountered without considerable investments of time and effort. However, Waldron et al. (2013) argue that the issue of inadequate funding to save biodiversity is a problem not only exclusive to developing countries, as even countries with better GDP typically allocate relatively less funding for biodiversity research. Therefore, in developing countries, studies on the ecological requirements of threatened avian species should be undertaken supported by funding provided by government agencies, as this generally makes policy-planning relatively easier for other government-run agencies that deal with policy implementation. We accordingly urge respective governments in the developing world to encourage researchers to engage in ecology-related research on threatened species by increasing the allocation of funds available for such studies. We agree with Morelli et al. (2021) that, worldwide, the most threatened bird species have relatively little protected area coverage. In India, for example, resident breeding bird species, such as Rhinoptilus bitorquatus, Ardeotis nigriceps, Houbaropsis bengalensis, Sypheotides indicus, Athene blewitti, Ophrysia superciliosa, and Perdicula manipurensis, the status of which is currently deemed to be threatened (Critically Endangered or Endangered), are generally distributed outside the confines of PAs and thus may have undergone population declines similar to those suffered by other threatened species elsewhere due to habitat loss (Hoffman et al., 2010). Nevertheless, effort to protect these species by creating more extensive PA networks and gaining more detailed information regarding dietary specialization are being made increasingly more difficult against a backdrop of expanding human populations, which prevents local and federal governments designating more areas as PAs. Moreover, traditional practices of hunting by local tribes, which often have valued cultural significance, make the enforcement of laws within existing PAs even more challenging (Datta et al., 2008). In this regard, although federal government has recently inaugurated an initiative to create Eco-sensitive Zones (ESZs) (MoEFCC, 2011) around PAs, which are designed to serve as “shock absorbers,” these will benefit only those species already inhabiting PAs and do little in the way of protecting threatened species distributed beyond PA boundaries. As such, this initiative is being cautiously implemented, given that NGOs, villagers, and civil society groups argue that ESZs curtail locals’ livelihood opportunities. However, although industrial-scale activities are strictly prohibited within these ESZs, only certain activities of villagers are regulated. We would like to thank the Director, Zoological Survey of India for support and encouragement. All authors declare that they have no conflicts of interest. Gopinathan Maheswaran conceived the idea and wrote the manuscript. Imran Alam and Amitava Majumder revised the manuscript, edited the manuscript, and support its content. Data sharing not applicable––no new data generated.

Factors Affecting Shellfish Quality in Terms of Faecal Contamination at Blakeney Point, East Anglia, UK

Relatively high E. coli and Faecal Streptococci (FS) numbers have been reported in the waters surrounding Blakeney Point, East Anglia, UK, an area containing significant shellfishery industries including mussels and cockles, despite the implementation of development works aimed at reducing residual contamination problems. The aim of this study was to evaluate the potential of using bacterial analyses and sterol profiling to assess the current levels and source of faecal pollution at Blakeney Point. No evidence of significant human faecal contamination of water in and around Blakeney Point could be found using either traditional microbiological analyses or sterol profile analysis. The presence of significant quantities of sitosterol, however, suggests that faecal contamination of water from birds does occur but at the concentration detected would not affect water quality. Analysis of cockles and mussels taken from the area show that negligible levels of coprostanol were present, confirming that faecal pollution was not causing any contamination issues. Apart from cholesterol, brassicasterol, an algal biomarker, as expected was dominant in shellfish flesh. The results confirm that current water treatment processes are successful in ensuring water quality at Blakeney Point and that a combination of microbial testing with sterol profile analysis confirmed that low microbial concentrations of faecal contaminants present in and around Blakeney Point most probably originate from migratory and/or resident bird species.

Impact of heavy metals pollution on the biochemical parameters and the histo-pathological picture of two resident wild birds at EL-Salam Canal area- North Sinai, Egypt

Heavy metals have been recognized as strong biological poisons because of their persistent nature, toxicity, tendency to get accumulated in the tissues of living organisms and their biological magnification that may cause severe health problems to human and wildlife. The aim of this study was to assess the concentrations of some heavy metals (Pb, Cd, Cu, Zn and Mn) in pectoral muscle, liver and kidney of 2 resident wild bird species (Laughing dove and Squacco heron) belonging to 2 different Families; trapped nearby El-Salam Canal from village Baloza; the northwestern part of Sinai, Egypt as a bio-indicator for the heavy metals pollution in the study area. Also to assess the impact of this pollution on the wild birds through biochemical parameters and histo-pathological examination. The current study revealed that, kidney of laughing dove showed the highest concentration of all examined metals with a significant difference (P˂0.05) with other tissues. Regarding to squacco heron, kidney showed the highest concentration of Cd, Cu and Mn with a significant difference (P˂0.05) with other tissues while liver showed the highest concentration of Pb and Zn with a significant difference (P˂0.05) with other tissues. This study showed increasing in the serum level of ALT and AST in the examined birds, however serum level of ALP was elevated only in laughing dove. Serum Creatinine was increased in squacco heron, while exhibits no change in laughing dove. Additionally urea was increased in all examined birds. Histo-pathological alterations were also recorded in the current study.

Population status and distribution of the critically endangered Indian Courser (Cursorius coromandelicus) on Delft Island, Sri Lanka

The critically endangered Indian Courser ( Cursorius coromandelicus) is a rare resident bird species in Sri Lanka. This bird species is restricted to the northern avifaunal region of Sri Lanka, and even there it has been recorded from only a few locations. Thus, it is identified as one of the rarest birds in Sri Lanka. A 1-year study was conducted to investigate Indian Courser population and their distribution within the Delft Island from 5th of January to 20th of December 2020. Ten (10) randomly selected points were investigated in this study. Of the 10 sampling points, the Indian Courser was observed within three (03) sampling points year around while several sightings were recorded in points 8, and 9 during 3 months of the year. Their abundance significantly varied among sampling locations (one-way ANOVA, F = 15.04, p < .05). The maximum number of individuals recorded was 18 ± 4.64 in December and the minimum number was 4 ± 4.64 during the non-migrant season. Although most of the area in the island is covered with dry grasslands, their distribution in Delft is largely confined to a few grassland patches where human activities are minimum. Hunting, egg collection, and trampling of their nest by the Delft ponies (feral horses) can be identified as the main threats of this species. It is of utmost importance to immediately implement holistic conservation measures to save this critically endangered bird as Delft is the only known location where a viable resident population of Indian Courser is found.

The role of urban waterbodies in maintaining bird species diversity within built area of Beijing

This study aims to provide a comprehensive understanding of the role of urban waterbodies in avian ecology, which is instructive for both biodiversity conservation and urban planning. Based on bird surveys conducted in 41 urban parks in Beijing during the breeding and wintering seasons of 2018–2019, and using standardized regression analyses, we identified the specific effects of waterbody attributes on the full avian community and forest bird guilds. We assessed this at multiple spatial scales, first within the focal parks, and then within buffer zones with radius of 200 m and 1000 m. We found that waterbodies can serve as avian diversity “hotspots” in the urban landscape. More specifically, they support avian diversity in the following ways: (1) Parks with waterbodies maintain a higher number of bird species than parks without waterbodies during the breeding season and attract resident forest birds during the wintering season. (2) When not frozen, waterbodies inside and outside parks contribute equally to resident forest bird species richness, while more individuals were attracted by waterbodies within neighborhoods. (3) In parks without waterbodies, the number of forest bird species significantly increases with the number of waterbody patches within neighborhoods, while the corresponding relationship for parks with waterbodies is insignificant. These findings suggest a preference for habitats nearby waterbodies among forest birds residing highly urbanized areas. This study provides new insights into avian ecology in urban landscapes and scientific support for the idea that creating and maintaining urban waterbodies can conserve biodiversity.

Genetic Evidence Documents Extra-Pair Paternity in Breeding Colonies of the Wood Stork Mycteria americana (Ciconiidae) in Cuba

The Wood Stork Mycteria americana is a rare resident bird species in the Caribbean, where it has small population sizes and reduced genetic variability. In the present study, we inferred the mating systems of the only two breeding colonies of Wood Stork known in the Caribbean, which are located in two of its most important wetlands: the Zapata Swamp Wetland and the Sabana-Camagüey Archipelago, both in Cuba. We sampled growing feathers of 27 chicks from 11 nests and analyzed genetic data from the most variable autosomal microsatellite loci described for the species. We estimated the relatedness between chicks by using the Queller-Goodnight coefficient and two maximum likelihood methods of kinship reconstruction. Evidence of monogamy was found in 27% of the nests analyzed, nest parasitism in the 36%, and extra-pair paternity in the 18%, while for the rest, inconsistencies among the methods were detected. Our results constitute the first evidence of extra-pair paternity for the Wood Stork and corroborate the usefulness of a non-invasive approach to perform kinship analysis in a poorly studied species.

LIVE FENCES HAVE GREATER DIVERSITY OF BIRD ASSEMBLAGES THAN GALLERY FORESTS IN HUMAN-MODIFIED ECOSYSTEMS

Anthropogenic activities have led to changes in land use resulting in fragmented areas with a reduction of biodiversity and ecosystem services. Gallery forests and live fences are common elements in Neotropical agricultural landscapes that could contribute to the conservation of bird species and the services they provide. However, we need to better understand how different tree cover types influence bird assemblages in order to conserve biodiversity. I analysed the diversity of bird assemblages in space and time across two cover types in three agricultural-livestock farms in Guanacaste, Costa Rica. Bird assemblages were sampled during 2019 using transects, covering both the dry and rainy season. I estimated richness and relative abundance of bird assemblages at each tree cover type and site. To characterize vegetation structure, I calculated plant richness, diameter at breast height and tree height. Patterns in bird diversity changed at a spatial scale, whereas remained similar in time. Bird assemblages had consistently higher richness and abundance in live fence than in gallery forest in the three study sites. In addition, live fences resulted in a less structural complexity compared to gallery forest, as indicated by decreased plant richness and tree height. My results show that live fences play an important role for birds, allowing for more diverse avian assemblages in human-modified ecosystems. Although live fences are less structurally complex and may offer less suitable habitats for birds than gallery forests, they might provide complementary food resources and act as stepping-stones for both resident and migratory bird species. Thus, live fences may perform as corridors for birds increasing connectivity in rural landscapes, which make them an essential tool for bird conservation.

Why a landscape view is important: nearby urban and agricultural land affects bird abundances in protected areas

Protected areas are one of the primary conservation tools used worldwide. However, they are often embedded in a landscape that is intensely used by people, such as for agriculture or urban development. The proximity of these land-use types to protected areas can potentially affect the ecological effectiveness (or conservation effectiveness) of protected areas. In this article, we examine to what degree adjacent agricultural and urban land uses affect the ecological effectiveness of protected areas over the greater Gauteng region of South Africa. We selected 198 common, resident bird species, and analysed detection/non-detection data for these species collected over regular grid cells (approximately 61 km2 in area). For each species, we estimated abundance per grid cell with the Royle-Nichols model in relation to the proportion of protected area as a covariate. Our study focused on how this relationship between proportion of protected area and abundance (which we term the ‘protection–abundance relationship’) changed as a function of other land-use types in the grid cell. Specifically, we examined the interaction effects between protected area and both urban and agricultural land-use type per grid cell on bird abundance. We assigned each species to one of seven guilds, namely: frugivores, gleaners, granivores, ground-feeders, hawkers, predators and vegivores, and examined how the protection–abundance relationship varied across guilds in relation to agriculture and urban area. As urban area within a grid cell increased, the protection–abundance relationship became more positive for 58% of all species. At the level of guilds, the protection–abundance relationship became more positive for two guilds (granivores and ground-feeders), more negative for frugivores, and remained unchanged for the other four guilds (gleaners, hawkers, predators and vegivores). As agricultural area within a grid cell increased, the protection–abundance relationship became more positive for 49% of all species. At the guild level, the protection–abundance relationship became more positive for six guilds (frugivores, gleaners, ground-feeders, hawkers, predators and vegivores) and remained unchanged for the granivores. Our results show land-use type near protected areas modified the effect protected areas had on bird abundances, and hence the ecological effectiveness of protected areas. Our results suggest that protected areas should be viewed as constituents within the landscape, rather than islands of protection.

Bird diversity, composition and response during COVID-19 in an urban landscape, Jamalpur, Bangladesh

The world has been encountering a COVID-19 pandemic since late 2019. The world’s people have also witnessed the free movement of wildlife, even in many urban areas in some countries during the imposed lockdown. We conducted research on the birds in the urban landscape of Jamalpur Sadar upazila from March 2020 to October 2020 during this pandemic situation. A total of 134 species of birds with 4338 individuals were recorded during the study period. The number of resident bird species was the maximum (115 species, 85.82%) compared to migrants. The highest number of birds was observed (120 species, 89.55%) and counted 2278 individual birds 52.51%) in the summer season. It was observed that the highest diversity of birds (89 species, 65.92%) was in March. The tree was the most (94 species, n = 2502) used microhabitat by birds in the study area. Among all birds, Pycnonotus cafer was the most abundant bird species with the highest relative abundance (6.11%). Some bird species (e.g. Metopidius indicus, Anastomus oscitans, Amaurornis phoenicurus, Streptopelia tranquebarica, Lonchura malacca) were frequently observed in the urban landscape of the study area during the pandemic. Proper management and awareness creation are essential for the conservation of the bird species in this area.
 Dhaka Univ. J. Biol. Sci. 30(2): 261-274, 2021 (July)

Avifauna of the Aiope River basin, Kunua District, north-west Bougainville Island

We present the results of a bird survey undertaken in the Aiope (Sarime) River basin in the Kunua District of north-west Bougainville, Papua New Guinea, during October–November 2019. Birds were surveyed across an elevational gradient of nearly 1,800 m, from the coast at the mouth of the Aiope River to the catchment headwaters in the north-west Emperor Range. Seventy-nine bird species were recorded, including three-quarters of Bougainville's resident land and freshwater avifauna (76/102 species) and a high proportion of its island-endemic and Solomons-endemic taxa (genera, species and subspecies). Resident avifauna include three species listed as threatened on the IUCN Red List—Sanford's Sea Eagle Haliaeetus sanfordi, Fearful Owl Nesasio solomonensis and (provisionally) Yellow-legged Pigeon Columba pallidiceps—nine Near Threatened species and two species that are protected under Papua New Guinean law. Forest supports 84% of the recorded resident bird species, most of which are forest-dependent, including all island-endemic taxa and all species of conservation concern apart from the Near Threatened Woodford's Rail Nesoclopeus woodfordi. Forest extent and condition improved with increasing elevation along the surveyed route; upper hill zone forest provides a narrow band of suitable habitat for a suite of lowland and hill forest species that were locally formerly more common across a broader altitudinal range. Elevational range extensions are reported for six species, and the vocalisations of Solomons Frogmouth Rigidipenna inexpectata are described from Bougainville for the first time.

On the Hunting of the Common Quail (Coturnix coturnix Linnaeus, 1758) Along the Mediterranean Coast of the Gaza Strip – Palestine

Palestine is a major route for migratory birds coming from Europe to Africa and vice versa. Both migratory and resident birds are commonly hunted for different purposes using different means in the Gaza Strip. The current descriptive study, which is the first of its kind, aims at introducing information on the hunting of the Common Quail (Coturnix Coturnix Linnaeus, 1758) in the Gaza Strip, which is a 365 km2 arid to semi-arid coastal zone lying in the southern part of the Palestinian coast along the eastern shore of the Mediterranean Sea. Since 2015, frequent field visits and discussions with bird hunters and other stakeholders have been carried out to get more information on quail hunting. Annually, hundreds of trammel or mist nets with camouflaging colors, having a height of about 2.5 meters and a distance of 100-200 meters off the coastline, are cleverly placed along the beach to hunt Common Quails and other non-target birds. Guns are used in hunting of quails scattering among inland low-growing vegetation types. The Common Quail is a source of livelihood for dozens of Gazan families, though it does not generate large sums throughout its hunting season. For several reasons, quail hunters claimed that the current quantities of Common Quails reaching the Gaza Strip do not exceed 20% of the amount that arrived 30-40 years ago. Along with the Common Quail, 50 migratory and resident bird species, with passerines making their half, were found to be incidentally caught in quail nets. Because of its feeding and healthy values, the demand of Gazans on Quail and its eggs is increasing day by day, and as a result, quail breeding was found to be a successful task in the Gaza Strip. The goodness of wild quail is many times greater than its farmed counterpart. The price of wild quail is USD 6-7 per pair, while the farmed counterpart is about USD 2 per pair. Finally, bird hunting should be regulated in the Gaza Strip in order to conserve wildlife in a sustainable fashion.

Prevalence and Genetic Diversity of Avian Haemosporidian Parasites in Southern Iran.

Avian haemosporidians are widespread and diverse and are classified in the genera Plasmodium, Haemoproteus, Leucocytozoon, and Fallisia. These species are known to cause haemosporidiosis and decreased fitness of their hosts. Despite the high diversity of habitats and animal species in Iran, only few studies have addressed avian haemosporidians in this geographic area. This study was performed in the south and southeast of Iran during the bird breeding seasons in 2017 and 2018, with the aim to partly fill in this gap. Blood samples of 237 passerine birds belonging to 41 species and 20 families were collected. Parasite infections were identified using a nested PCR protocol targeting a 479-base-pair fragment of the mitochondrial cytochrome b (cytb) gene of Haemoproteus, Plasmodium and Leucocytozoon species. The overall prevalence of haemosporidian parasites was 51.1%, and 55 different lineages were identified, of which 15 cytb lineages were new globally. The lineages of Haemoproteus predominated (63.6% of all detected lineages), followed by Leucocytozoon and Plasmodium. Nineteen new host records of haemosporidian cytb lineages were identified, and the majority of them were found in resident bird species, indicating local transmission. Thirteen co-infections (9.8% of infected individuals) of Haemoproteus and Leucocytozoon parasites in seven host species were observed. This study shows the presence of active local transmission of parasites to resident bird species in the southeast of Iran and contributes to the knowledge on haemosporidian parasite biodiversity in this poorly studied region of the world.

Conservation monitoring of a polluted urban river: an occupancy modeling study of birds in the Yamuna of Delhi

Given that ecological knowledge of large urban river systems is extremely sparse due to logistics and accessibility an occupancy modeling study was conducted on the resident birds of Delhi. River Yamuna passing through Delhi is a refuge for several resident and migratory species of birds but its water quality has been deteriorating due to ever growing population, contributing most of its pollution load in the urban center. The objectives of this study were 1) to determine whether the occupancy of common waterbirds varied between differential polluted sections of the river, 2) to better understand the associations between habitat variables and use of the river habitat by common waterbirds and 3) to identify whether any species or groups of species could be useful as indicators for habitat quality. The occupancy parameter Ψ was estimated for 17 common resident species among 68 species, recorded from 176 sampling locations during 2018, on the banks of river. Species occupancy was estimated as a function of habitat variables such as physico-chemical characteristic of water, solid waste, percent area of surface and emergent vegetation and human disturbance at each sampling site. The results suggest that Little Grebe (Tachybaptus ruficollis), Grey Heron (Ardea cinerea), Grey-headed Swamphen (Porphyrio poliocephalus), Eurasian Coot (Fulica atra), Common Moorhen (Gallinuala chloropus), Purple Heron (Ardea purpurea) and Little Cormorant (Microcarbo niger) are negatively associated with the Total Dissolved Solute (TDS). Interestingly, occupancy of Black-winged Stilt (Himantopus himantopus) is negatively associated with pH but positively with solid waste strongly suggesting its preference for the polluted sections of the river, possibly due to the increased availability of food. For river Yamuna, estimates of Ψ for various birds forms a baseline to study future trends. This study also indicates that species like Black-winged Stilt, can serve as an indicator of contaminated water bodies. The challenges posed by increasing urbanization and pollution to riparian bird habitats in urban areas can be effectively dealt with by incorporating such ecological knowledge with habitat restoration and conservation efforts.

Evidence for circadian-based photoperiodic timekeeping in Svalbard ptarmigan, the northernmost resident bird

The high Arctic archipelago of Svalbard (74°-81° north) experiences extended periods of uninterrupted daylight in summer and uninterrupted night in winter, apparently relaxing the major driver for the evolution of circadian rhythmicity. Svalbard ptarmigan (Lagopus muta hyperborea) is the only year-round resident terrestrial bird species endemic to the high Arctic and is remarkably adapted to the extreme annual variation in environmental conditions.1 Here, we demonstrate that, although circadian control of behavior disappears rapidly upon transfer to constant light conditions, consistent with the loss of daily activity patterns observed during the polar summer and polar night, Svalbard ptarmigans nonetheless employ a circadian-based mechanism for photoperiodic timekeeping. First, we show the persistence of rhythmic clock gene expression under constant light within the mediobasal hypothalamus and pars tuberalis, the key tissues in the seasonal neuroendocrine cascade. We then employ a "sliding skeleton photoperiod" protocol, revealing that the driving force behind seasonal biology of the Svalbard ptarmigan is rhythmic sensitivity to light, a feature that depends on a functioning circadian rhythm. Hence, the unusual selective pressures of life in the high Arctic have favored decoupling of the circadian clock from organization of daily activity patterns, while preserving its importance for seasonal synchronization.

Diversity of birds recorded at different altitudes in central Nepal Himalayas

Factors determining the spatial distribution of bird species along altitudinal gradients have been important in their ecological and biogeographical research. Here, have used the data on bird species recorded in Manang, central Nepal Himalayas and attempt to determine the drivers of bird species diversity. We also carried out indicator species analysis to observe if any bird species are associated with different altitudinal ranges and land use gradients. We recorded 1331 individuals belonging to 82 species of both resident and itinerant birds. In our study, altitude was the major factor determining species richness and abundance. Position of study localities is main factor determining bird community composition. Diversity of bird species were mainly found in habitats that were far human settlements, having high annual mean temperature and more roughness. Species diversity was high during July-August compared to September-October and in north-facing slopes, and also in shrub and tree covered areas than grassland and places with mostly snow and grassland. Indicator species analysis showed only 21 species were significantly associated with altitudinal gradients, mostly below 3000 m a.s.l. and only eight bird species were associated with two land use gradients (grassland and snow-glacier). In conclusion, position of sampled localities, altitude, aspect, land use types and different climatic factors were important determinants of bird diversity along altitudinal gradients in Manang. To protect bird diversity in Manang, we need to protect habitats that are located mainly in low altitudes for most of the bird species. However, high altitude habitats with snow and glaciers are also important for few bird species. Thus, a large area with heterogenous habitats is important for bird species management and conservation.

Biological Properties and Genetic Characterization of Novel Low Pathogenic H7N3 Avian Influenza Viruses Isolated from Mallard Ducks in the Caspian Region, Dagestan, Russia.

Avian influenza viruses (AIVs) are maintained in wild bird reservoirs, particularly in mallard ducks and other waterfowl. Novel evolutionary lineages of AIV that arise through genetic drift or reassortment can spread with wild bird migrations to new regions, infect a wide variety of resident bird species, and spillover to domestic poultry. The vast continental reservoir of AIVs in Eurasia harbors a wide diversity of influenza subtypes, including both highly pathogenic (HP) and low pathogenic (LP) H7 AIV. The Caspian Sea region is positioned at the intersection of major migratory flyways connecting Central Asia, Europe, the Black and Mediterranean Sea regions and Africa and holds a rich wetland and avian ecology. To understand genetic reservoirs present in the Caspian Sea region, we collected 559 cloacal swabs from Anseriformes and other species during the annual autumn migration periods in 2017 and 2018. We isolated two novel H7N3 LPAIV from mallard ducks whose H7 hemagglutinin (HA) gene was phylogenetically related to contemporaneous strains from distant Mongolia, and more closely Georgia and Ukraine, and predated the spread of this H7 LPAIV sublineage into East Asia in 2019. The N3 neuraminidase gene and internal genes were prototypical of AIV widely dispersed in wild bird reservoirs sampled along flyways connected to the Caspian region. The polymerase and nucleoprotein segments clustered with contemporaneous H5 HPAI (clade 2.3.4.4b) isolates, suggesting the wide dispersal of H7 LPAIV and the potential of this subtype for reassortment. These findings highlight the need for deeper surveillance of AIV in wild birds to better understand the extent of infection spread and evolution along spatial and temporal flyways in Eurasia.