Avifaunal diversity and conservation status of waterbirds in Pillaimadam Lagoon, Palk Bay, India

Biodiversity-rich areas tied to heritage, religious tourism, and ecotourism, often face changes to their landscapes due to infrastructure development. Such activities may threaten the species survival and disrupt the delicate ecosystems in these regions. Hence it becomes imperative to build up baseline species data from such areas for biodiversity conservation and management interventions. Towards achieving this objective, avifaunal inventories were documented from Kothandaramar Lagoon, Dhanushkodi Lagoon, and the Arichalmunai beach in Rameswaram Island, Ramanathapuram District, Tamil Nadu, which is an important site for winter migrants. A total of 147 avian species belonging to 17 orders and 45 families from August 2021 to July 2023 were recorded. Order-wise, Charadriiformes (52 species) dominated the area, followed by Passeriformes (27 species) and Pelecaniformes (21 species). According to the IUCN Red List of Threatened Species, 11 ‘Near Threatened’, three ‘Vulnerable’, two ‘Endangered’ (Great Knot Calidris tenuirostris and Siberian Sandplover Anarhynchus mongolus), and one unassessed species (Hanuman Plover Charadrius seebohmi) were recorded. The relative abundance based on the frequency of observations indicated that 61% (90 species) were common, 22% (32 species) were uncommon, and 17% (25 species) were rare. Winter visitors constituted 42% (62 species) and one was a passage migrant (Rosy Starling Pastor roseus). Coastal lagoons of this region comprise diverse habitats that play a vital role for birds, which provide places for nesting, roosting, and foraging. This baseline data emphasizes the importance of Dhanushkodi Lagoon along with adjacent areas as an important wintering site on the southeastern coast of India for migratory shorebirds as well as highlights the importance of adjoining small forested patches thus required to be declared as a protected area.

Pakistan is recognized for its diverse avifauna, particularly as a wintering ground for numerous migratory species that arrive via the Central Asian Flyway (CAF) and neighboring regions. In 2025, Pakistan documented a significant record of the Blue-and-White Flycatcher (Cyanoptila cyanomelana), a migratory songbird belonging to the family Muscicapidae, observed on January 11 at the Mehrano Wildlife Sanctuary in Sindh (GPS coordinates: 27°18'16"N 68°41'09"E). Four individuals were photographed to provide evidence-based documentation, and their characteristics were meticulously analyzed using sonograms and taxonomical attributes. The Blue-and-White flycatcher is a winter visitor to Southeast Asia including India, where sightings are infrequent. This observation represents the first documented occurrence of the species in Pakistan, supported by direct field observations and photographic evidence. This remarkable discovery constitutes a significant enhancement to the region’s avifaunal diversity and underscore the conservation initiatives undertaken by the Sindh Wildlife Department. This rare and elusive record of the Blue-and-White Flycatcher offers valuable insights into the migration patterns of avian species in South Asia, highlighting the necessity for monitoring and conserving critical habitats within protected areas.

Simple SummaryThe Hengduan Mountain area in southwest China is an important migratory channel for migratory birds in the Central Asian flyway. The lakes along the way have different ecological functions for the life histories of waterbirds. In order to determine the ecological functions of high-altitude lakes, we selected Mangcuo Lake in Markam County to investigate the waterbird community in four seasons. The results show that Mangcuo Lake provides a breeding habitat for nine species of birds and also supports excellent numbers of birds migrating in the spring and autumn. In view of the role of Mangcuo Lake in the migration route, we propose upgrading the protection level of the Mangcuo Lake.The stopovers provide food and habitat for migratory birds and therefore play an important role in facilitating the birds’ completion of their migration. The Hengduan Mountains, which have a complex topography, are located in a large corridor of the Central Asian migratory flyway, so the lakes along the Hengduan Mountains are important for waterbird migration. The existing research on lakes in the Hengduan Mountain area is mostly concentrated in the central and southern parts of the mountains, which proves that many lakes are wintering grounds for migrating birds. We wonder whether the ecological functions of lakes will change more with further elevation. With this question, we conducted four surveys for the seasonal bird survey in Mangcuo Lake, which is located in the northwest of the Hengduan Mountains, in Markam County of Qamdo City, between October 2019 and July 2020. We recorded a total of 6109 birds from 20 species of waterbirds, including 20 species of migratory waterbirds, accounting for 100% of all bird species. The diversity and richness of waterbirds in Mangtso Lake is shown as spring > autumn ≥, summer > winter, with no waterbirds in winter. The black-necked grebe (Podiceps nigricollis), great crested grebe (Podiceps cristatus), bar-headed goose (Anser indicus), and ruddy shelduck (Tadorna ferruginea) were the dominant species in the waterbird community. The highest number of waterbird species and total individuals were found in the transition zone between the marsh wetlands and lakes, and the number of waterbird species differed significantly among habitats (X2 = 14.405, p = 0.000), with habitat complexity being an important factor influencing waterfowl abundance and distribution. The IUCN Red-listed species recorded include the black-necked crane (Grus nigricollis), painted stork (Mycteria leucocephala), and common pochard (Aythya ferina). By comparing with other lakes in Hengduan Mountain, we found that the ecological functions of the plateau lakes in the Hengduan Mountains, to support the life histories of migrating waterbirds, are gradually transforming as the altitude rises, and can be divided into approximately three levels, with the first level of Qionghai, Chenghai, Erhai, and Jianhu at altitudes of 1500–2200 m being the most important ecological function in terms of providing wintering grounds for migrating birds. The second layer, at an altitude of 2400–3300 m, includes Lashihai, Lugu Lake, and Napahai, which are not only wintering wetlands for migratory birds but also important stopover sites. The third layer of Mangcuo Lake, which is above 4000 m above sea level, provides a breeding ground for some migratory waterbirds in summer and a migratory resting place for migratory waterbirds in spring and autumn. We advocate for the importance of Mangcuo Lake in the alpine region along the central Asian flyway, as well as emerging nature conservation action that was previously neglected.

The present study was carried out in the Kachchh district, Gujarat. Kachchh falls under Central Asian Flyway (CAF). Virtually information is scanty on the waterbirds of Kachchh. Hence the present study was undertaken to assess the factors influencing the wetland bird populations in six different wetlands in Kachchh district. Standard methods (Direct and block count) were followed for enumerating the waterbird populations. The analysis of the water quality parameters was carried out as per the standard methods prescribed in APHA (1998). A total of 83 species of waterbirds were observed. Pearson correlation and Stepwise multiple regression analysis were carried out to find out the relationship between the waterbirds and physico-chemical parameters and factors influencing the density, diversity and richness of waterbirds, respectively. The density of waterbirds is influenced by water depth and sediment pH. The diversity of waterbirds is predicted by water conductivity and the richness of waterbirds is influenced by salinity and water temperature.

Any new economic activity in a virgin area brings landscape changes, making it essential to document baseline biodiversity areas to understand the impacts on habitats. Avifaunal inventories are critical for previously undocumented areas, especially in a wintering site for shorebirds in the Central Asian Flyway, to formulate site- and species-specific conservation management tools. We present an annotated checklist of avifauna from the Valinokkam Lagoon in the Ramanathapuram district of Tamil Nadu. We recorded the first baseline avifaunal data for 154 species belonging to 16 orders and 46 families from August 2016 to February 2023. Order-wise, Charadriiformes dominated the study site with 47 species; followed by Passeriformes with 39 species and Pelecaniformes with 20 species. Winter visitors constituted 37.6 % (58 species) and one Passage Migrant Rosy Starling Pastor roseus. The relative abundance indicated that 94 species were C (common), 41 species were UC (uncommon), and 19 species were Ra (rare). Eleven Near Threatened (NT) species: Oriental Darter Anhinga melanogaster, Painted Stork Mycteria leucocephala, Black-headed Ibis Threskiornis melanocephalus, Spot-billed Pelican Pelecanus philippensis, Black-tailed Godwit Limosa limosa, Bar-tailed Godwit Limosa lapponica, Great Stone-curlew Esacus recurvirostris, Eurasian Curlew Numenius arquata, Curlew Sandpiper Calidris ferruginea, Red-necked Stint Calidris ruficollis and Red Knot Calidris canutus, one Endangered (EN) species Great Knot Calidris tenuirostris, and one unassessed Hanuman Plover Charadrius seebohmi according to the IUCN Red List category. This baseline data highlights the importance of Valinokkam Lagoon as an important wintering site in the Central Asian Flyway on the southeast coast of India for migratory shorebirds and the need for more conservation priorities for regional endemic birds like Hanuman Plover.
 

Seaweed production in India is primarily confined to the Gulf of Mannar and Palk Bay in Tamil Nadu, South India. Around 5,000 fishers in this region are involved in wild seaweed collection. Gathering the gender-disaggregated data, perhaps more qualitatively, explains gender differences and helps redress inequalities. With this rationale, a study was undertaken in the the Ramanathapuram District, Tamil Nadu, with a sample of 60 households to assess the gender dimensions in wild seaweed harvesting. The social participation, extension participation, extent of usage of information sources, daily activity profile, drudgery, technology adoption, attitude towards seaweed harvesting/fishing as a livelihood, gender empowerment dimensions, gender needs and constraints were analysed. The study revealed that women have a prominent role in most activities in seaweed harvesting. There is a significant difference between men and women seaweed harvesters with regard to above aspects except for their attitude towards seaweed harvesting as a livelihood. Furthermore, a significant difference exists between women seaweed harvesters, men seaweed harvesters and fishermen regarding various dimensions. Gender disparities exist in asset ownership, access to resources and services, usage of information sources and being overwhelmed with productive and reproductive roles. Strategies may include promoting joint ownership, gender-sensitive extension activities, gender-specific skill development, gender-friendly technological interventions and gender sensitisation. Keywords: Gender analysis, Gender empowerment dimensions, Seaweed harvesters, Wild seaweed harvesting

Cultivated Kappaphycus alvarezii Doty (Doty) was analyzed for its dryweed quality (moisture and clean anhydrous weed (CAW) contents), carrageenan (semi-refined carrageenan (SRC)) yield, and gel strength with respect to environmental parameters (seawater temperature, salinity, nitrate, and phosphate) for 1 year from April 2012 to March 2013 from three different localities, viz., Mangadu, Munaikadu, and Vedalai, located in Palk Bay, Ramanathapuram District, Tamil Nadu, Southeast coast of India. Dryweed quality, viz., moisture content (35.00 ± 0.00 to 38.39 ± 0.19 %), clean anhydrous weed (39.26 ± 1.37 to 45.22 ± 0.57 %), and carrageenan (SRC) yield (33.30 ± 1.23 to 38.50 ± 0.20 to 0.30 %) with gel strength (379.05 ± 6.07 to 486.44 ± 5.57 g cm−2), was found to vary differently at all the sites during the study period. Two-way ANOVA showed that seawater temperature, salinity, and nitrate were significant spatially, while carrageenan (SRC) yield and gel strength were found to be significant (p = 0.05 level) both spatially and temporally. The carrageenan (SRC) obtained in this study met international specifications with respect to dryweed quality, carrageenan yield, and gel strength, suggesting its production indigenously for internal consumption as well as for export using the cultivated raw material and thus providing employment to the coastal rural people in India and earning foreign exchange.

Avifaunal inventories are crucial to the formulation of conservation and management strategies for habitats and species. An annotated checklist of the birds of the Karangadu eco-tourism area located in the Palk Bay in Ramanathapuram district of Tamil Nadu, was prepared. We listed a total of 107 species belonging to 18 orders and 40 families. Orders Charadriiformes, Suliformes, and Pelecaniformes dominated the habitat. Among the families, Scolopacidae (10 species) was dominant, followed by Ardeidae (9), and Laridae (8). In addition, the study also documented three globally ‘Near Threatened’ species: Painted Stork Mycteria leucocephala, Black-tailed Godwit Limosa limosa, and Black-headed Ibis Threskiornis melanocephalus. The observed frequency of the species was: 57% (61 spp.) common, 32.7% (35 spp.) uncommon, and 10.3% (11 spp.) rare. Categorization based on the residential status of birds revealed that 31% (33 spp.) were winter visitors, and one was a passage migrant (Rosy Starling Pastor roseus). These baseline data highlight the importance of Karangadu as an important site on the southeastern coast of India for migratory shorebird conservation priorities.

The present study aims to survey the avifaunal diversity in some selected localities in and around Madurai City, Tamil Nadu during June 2021 to April 2022. Birds were surveyed using short-strip transects counts (SSCT) method. A total of 99 species of birds belonging to 44 families and 86 genera have been recorded in Madurai city, of which 78 species are resident, 14 species are migrant and 7 species are local migrants. The Ardeidae were the most prominent family with 11 species, and their relative diversity index was the highest (RDi = 11.11). Carnivores’ bird community was found to be dominant among foraging pattern. According to their frequency of occurrence, 57 species (57.57%) were very common, 30 (30.30%) common and 12 (12.12%) rare. IUCN threat categories classify four species as “Near Threatened” and 95 species as “Least Concern”. The present study reveals the highest birds species diversity (Shannon’s), richness (Margalef’s), and evenness (Pielou’s) indices were found in the Madakulam area when compared to that of other study areas. Based on the occurrence of bird species in ten different areas, we can conclude that the diversity and richness of bird species increases with increased vegetation areas and decrease with greater human disturbances. Additionally, researchers have reported that anthropogenic disruptions will reduce the diversity of bird species, as well as other issues such as habitat loss, overhunting, structural collisions, pollution, climate change etc.

A comprehensive inventory of faunal and floral species in a specific region holds significant value for scientific investigation. This study was conducted between 2015 and 2021, especially during the winter season, in Pakhibitan Bird & Wildlife Sanctuary (also known as Gajoldoba wetland) in West Bengal, which was established in 2016. This wetland surrounded by forests is located on the upper section of the Teesta Barrage in the Dooars region of Jalpaiguri District, and it attracts birds from the Central Asian Flyway. Around 124 bird species belonging to 14 orders and 37 families were documented. Passeriformes with 32 species, and Anatidae with 23 species, are the most abundant groups. Based on the IUCN Red Data Book (2022–23), six species are Near Threatened, four are Vulnerable, and one Endangered. About 50% of birds were resident, 44% migratory, and 6% local migrants.

The Majalgaon Reservoir, located in Beed district, Maharashtra, serves as a significant wetland ecosystem, providing habitat to a diverse range of avifaunal species. This study aims to document the diversity and ecological significance of the avifauna in and around the reservoir. The survey of avifauna was carried out for one year (January 2024 to december 2024). A total of 36 bird species were identified during the study. There are 23 families represented among the recorded bird species. The species belong to 1o different orders. The dominant family is Ardeidae with 5 species, including Little Egret, Cattle Egret, Large Egret, Grey Heron and Indian Pond Heron. This dominance indicates the importance of wetlands and aquatic habitats in supporting a diverse range of water birds in the reservoir area. Out of the 36 species, 34 are classified as Least Concern (LC), indicating that they are not currently facing significant threats. However, two species—the Oriental Darter and the Black-winged Pratincole are classified as Near Threatened (NT), meaning they are at risk of becoming vulnerable if existing threats persist. Additionally, several species, including the Black-winged Pratincole and the Rosy Starling, are migratory, emphasizing the importance of conserving their breeding and wintering habitats. The study underscores the importance of the Majalgaon Reservoir as a biodiversity hotspot and calls for the implementation of conservation measures to mitigate threats such as habitat degradation, water pollution, and human disturbances. This research provides baseline data for future studies and contributes to the understanding of wetland ecosystems in semi-arid regions, emphasizing the need for integrated management strategies to ensure the long-term sustainability of avifaunal diversity in the region.

Seasonal observation on trace elements of shallow inner shelf sediments and their correlation with the population of recent benthic ostracoda off Rameswaram, Ramanathapuram District, Tamil Nadu, Southeast coast of India is the aim of this study. The sediments were analysed for trace elements Al, Fe, Mn, Zn, Cu, Pb, Cd, Ni, Co and Cr and being correlated with the population of benthic ostracoda for four different seasons. Cu has a positive correlation, and Fe, Mn, Zn, Pb, Cd, Ni, Co and Cr have negative correlation with the total population of ostracoda. Al has no considerable correlation with the total population of ostracoda. In the middle segment plenty of corals were found in the study area and their effect being discussed.

Since 2016, the highly pathogenic avian influenza H5N8 virus has emerged in the Central Asian flyway and Europe, causing massive deaths in poultry and wild birds. In this study, we isolated and identified three H5N8 viruses from swan goose and black swans in Hubei province during the 2016/2017 winter season. Whole-genome sequencing and phylogenetic analysis revealed that the three viruses clustered into a group of H5N8 viruses from Qinghai Lake and Europe. A novel reassortment virus from swan goose was distinguished from that of black swans, in that its PA and NP genes were distinct from those of Qinghai Lake viruses. Molecular dating revealed that the ancestral strain of these H5N8 viruses emerged around July 2015. From sequence comparison, we discovered eight amino acid substitutions in HA and NA during the adaption process from poultry to wild birds. The three viruses were isolated from wild birds in the East Asian-Australasian flyway; however, the viral genomes were similar to H5N8 viruses circulating along the Central Asian flyway. From these data, we conclude that wetlands and lakes in Central China may play a key role in disseminating H5N8 viruses between the East Asian-Australasian and Central Asian flyways.

Urban growth is a major threat to biodiversity conservation at the global scale. Its impacts are expected to be especially detrimental when it sprawls into the landscape and reaches sites of high conservation value due to the species and ecosystems they host, such as protected areas. I analyzed the degree of urbanization (i.e., urban cover and growth rate) from 2006 to 2015 in protected sites in the Natura 2000 network, which, according to the Habitats and Birds Directives, harbor species and habitats of high conservation concern in Europe. I used data on the degree of land imperviousness from COPERNICUS to calculate and compare urban covers and growth rates inside and outside Natura 2000. I also analyzed the relationships of urban cover and growth rates with a set of characteristics of Natura sites. Urban cover inside Natura 2000 was 10 times lower than outside (0.4% vs. 4%) throughout the European Union. However, the rates of urban growth were slightly higher inside than outside Natura 2000 (4.8% vs. 3.9%), which indicates an incipient urban sprawl inside the network. In general, Natura sites affected most by urbanization were those surrounded by densely populated areas (i.e., urban clusters) that had a low number of species or habitats of conservation concern, albeit some member states had high urban cover or growth rate or both in protected sites with a large number of species or habitats of high conservation value. Small Natura sites had more urban cover than large sites, but urban growth rates were highest in large Natura sites. Natura 2000 is protected against urbanization to some extent, but there is room for improvement. Member states must enact stricter legal protection and control law enforcement to halt urban sprawl into protected areas under the greatest pressure from urban sprawl (i.e., close to urban clusters). Such actions are particularly needed in Natura sites with high urban cover and growth rates and areas where urbanization is affecting small Natura sites of high conservation value, which are especially vulnerable and concentrated in the Mediterranean region.

Humans benefit from a variety of ecosystem services provided by seagrass meadows. However, seagrass conservation efforts appear to be insufficient, as evidenced by its low representation in marine protected areas around the world. Protecting seagrasses benefits not just the seagrass itself, but also the macro‐benthic invertebrate assemblages that dwell beside it and contribute indirectly to the various environmental services through their functions. Studies comparing seagrass‐associated invertebrate assemblages and functional trait composition within and outside marine protected areas are uncommon, so the current study compares invertebrate assemblages and functional trait composition from a marine protected area (Gulf of Mannar Marine National Park) and an adjacent non‐marine protected area (Palk Bay) along the southeast coast of India. The species richness (meanS = 83.3) and density (meanD = 6276.6) of seagrass‐associated macro‐molluscs were higher in marine protected areas than in non‐marine protected areas (meanS = 54.6, meanD = 5264.0), but not the species diversity (meanH′ = 2.1 for marine protected areas; meanH′ = 2.0 for non‐marine protected areas). Protected seagrass ecosystems, on the contrary, exhibited much higher species richness within functional groups (i.e., deposit feeders [meanS = 5.5], micro‐/macro‐grazers [21.7], predators [34.8], ectoparasites [2.1], and suspension feeders [19.3]), suggesting that the protection status supports functional redundancy. The study's findings reveal the importance of protection status in enhancing macro‐mollusc assemblages in seagrass ecosystems, which improves the ecosystem's resilience and function.