The high rate of wetland degradation, which has reached over 40 percent in the past 30 years, has raised conservation concerns worldwide. The role of local communities in assessing wetland health has not been integrated with scientific approaches, and efforts are needed to harmonise these perspectives. This study examines the health of the Driefontein wetlands, a Ramsar site, by evaluating the distribution and composition of vegetation and bird species as indicators of wetland health during the dry season. Five 10 m x 50 m zones were established around each of five selected pools and subdivided into quadrants for sampling wetland indicator vegetation, in accordance with the Environmental Management Agency's Wetland Species Indicator Guide. Bird counts were conducted twice a day, once a week, over four months during the dry season. Findings revealed variations in vegetation richness and diversity across various zones, with species richness and diversity decreasing as distance from the water source increased. The 10-20 m and 20.1-30 m zones exhibited the highest species richness (R=14) and diversity (Shannon indices of 2.216 and 2.188, respectively), while the 40.1-50 m zone had the lowest (R=10, Shannon = 1.2). Dominant species in the 10-20 m zone included Typha latifolia subsp. capensis (31.5%) and Phragmites australis (17%). Species richness declined with distance, with some species failing to thrive beyond 30 m. Bird counts indicated dominance by egrets (66.9%) and cranes (15.3%), with Bubulcus ibis (49.2%) being the most prevalent indicator of wetland birds. The combined use of vegetation and avian indicators for wetland health assessment offers greater opportunities to inform development and conservation efforts.

Six field surveys were conducted from July 2024 to May 2025 in six sessions (three during dry and three during wet seasons) along 10 fixed transects (five in the core zone and five in the buffer zone) to assess the bird species composition and spatial distribution in the bird sanctuary planning zone of the Can Gio Mangrove Biosphere Reserve, after 47 years of restoration (1978–2025). A total of 57 bird species, representing 11 orders, 32 families, and 45 genera were recorded, including 18 waterbird species. Four species are listed as threatened and prioritized for conservation by the IUCN Red List: Porzana paykullii as Near Threatened, Vietnam Red List Book: Anhinga melanogaster and Mycteria leucocephala as Vulnerable, and Vietnamese law: Milvus migrans and Anhinga melanogaster as prioritized for conservation. The order Passeriformes was the most species-rich (21 species), while Pelecaniformes had the highest number of individual encounters (2,427). Overall, bird diversity in the area was relatively high (Shannon-Wiener index H’ = 2.60 ± 0.34), with a moderate level of dominance (Simpson D = 0.12 ± 0.06). Species abundance was uneven across seasons and transects, with higher diversity and abundance during the wet season, although the differences were not statistically significant. Only the transect L8 in the buffer zone showed statistically significant differences in diversity and abundance, representing a newly recorded breeding area dominated by waterbird species such as Nycticorax nycticorax, Egretta garzetta, Ardea intermedia, and Microcarbo niger. Compared to a 2019 study, the number of breeding species in the core zone declined to seven species with approximately 1,000 individuals, while a new breeding area in the buffer zone was identified with eight breeding species and approximately 1,500 individuals. Continuous monitoring and conservation efforts are necessary to sustain and manage avian biodiversity in this critical wetland ecosystem.

This article analyzes the results of observations of bird migrations in the northern part of the Ukrainian Carpathians in late summer – mid-autumn 2023. The dynamics of the species composition and number of birds in the Polonyna Runa mountain range was determined, and the heights and directions of their flights through the study area were determined. During 67 days of continuous observations, 65 species of birds from 12 orders were recorded – 42 non-target species and 23 target species. The number of non-target species (one species each of Columbiformes, Cuculiformes, Apodiformes, Coraciiformes, three species of Piciformes and thirty-five species of Passeriformes) was low (n = 7596 individuals, or 109.96 individuals./day). The subalpine part of this massif is significantly inferior to the forests along its slopes, settlements and adjacent agricultural lands located along small mountain rivers and streams in terms of the number of species and the number of individuals of non-target birds. Target species (Anseriformes, Gruiformes, Pelecaniformes, Ciconiformes, Charadriiformes, Falconiformes, Strigiformes) also had rather low numbers (n = 2619 individuals, or 9.77 individuals/day), with Grus grus accounting for more than 74.8% (n = 1960 individuals). The vast majority of the target species flew at low altitudes (50.0% of individuals – up to 100 m above the level of the mountain meadow), mostly in the southwestern direction (74.8% of individuals and 28.4% of flights): in August – 8.6% of ind. and 11.2% of flights, in September – 56.8% of ind. and 22.7% of flights, in October – 83.8% of ind. and 46.3% of flights. Given the low altitudes and multidirectional flights (especially in late August and the first half of September), most birds at Polonyna Runa are wandering rather than migrating in the fall. Most of the birds observed there are probably migrating from the Predkarpattya and mountain valleys of Carpathian to Zakarpattia, or staying for rest, feeding and waiting out unfavorable weather conditions during migration. Apparently, the small number of flights and low number of birds in Polonyna Runa is due to the fact that most of them bypass this area through intermountain valleys and low passes. In addition, at the top of Polonyna Runa there are no proper conditions for feeding many species due to the replacement of pastures with almost continuous dense medium-high thickets of grass vegetation.

This study investigates the species composition and distribution of gallinaceous birds (Galliformes) in the south of eastern Europe, specifically within the territory of present‐day Ukraine, during the Late Pleistocene and Holocene. The research is based on the comprehensive revision of skeletal remains found at archaeological sites. The findings reveal that seven galliform species were present in the region during these periods: hazel grouse, willow ptarmigan, rock ptarmigan, capercaillie, black grouse, grey partridge and common quail. The study highlights the crucial role of the Crimean Mountains as a refugium during the last glaciation, where the greatest diversity of gallinaceous birds was observed. The research also addresses the changes in the distribution and abundance of these birds over time, noting the loss of some species and the appearance of others. The findings underscore the importance of understanding past environmental changes and their impact on bird populations, which can inform current conservation efforts. The study concludes that while some species have shown high ecological plasticity and adaptability, others have experienced significant range contractions requiring targeted conservation measures.

The Central Himalaya biodiversity hotspot in India provide critical ecosystem services. The region is also developing at an unprecedented rate, both economically and demographically resulting in extensive forest fragmentation. Such activities are likely to influence avian faunal diversity, which raises the concern over vulnerable species with restricted ranges and specialised requirements. The Black capped Kingfisher Halcyon pileata is vulnerable and identifying the landscape heterogeneity with respect to riverine forest patches and inland riverine forest patches, where the species occurs can influence the temporal dynamics of bird species richness and composition. Here, we report the occurrence of Halcyon pileata in riverine forests of the Shiva Khola of the Darjeeling District of the state of West Bengal, extending the previously known range of the species in the country.

This study was conducted in the Yerevan Botanical Garden from 2022 to 2023. The transect method, widely recognized for its effectiveness in studying bird populations across diverse habitats, was employed to monitor birds in the garden. To assess bird diversity, we utilized two widely accepted diversity indices: the Shannon-Wiener index and the Simpson diversity index. Over the course of the research, 54 bird species were recorded in the Botanical Garden. These included 16 sedentary species, 13 nesting species, 9 wintering species, and 9 migratory species. Additionally, 7 species were observed sporadically as single (random) occurrences. Notably, we documented an unexpected observation of Eurasian Siskin (Spinus spinus) in June, a species traditionally considered a wintering bird according to the available literature. Seasonal variations in species composition and abundance were evident. The highest species richness was recorded in open habitats during spring, while the lowest was observed in forest habitats during autumn. Similarly, the number of individual birds peaked in open habitats during summer and declined in winter. The presence of five threatened species, including four listed in the Red Book of the Republic of Armenia and two on the IUCN Red List, underscores the Yerevan Botanical Garden’s significance as a sanctuary for bird conservation.

Under conditions of increasing urbanization, the problem of studying the impact of synanthropic animal species on the functioning of urban ecosystems is becoming increasingly important. The purpose of this study was to identify and analyze the species composition of synanthropic birds and mammals in the urban area of Osh (Kyrgyzstan), assess the degree of their bio-damaging activity, and develop recommendations to minimize their negative impact on various sectors of the urban environment. Field studies conducted in 2023–2024 revealed 22 species of synanthropic birds and 7 species of synanthropic mammals. Among birds, representatives of Columbiformes (3 species), Apodiformes (2 species), and Passeriformes (18 species) were identified, including families Hirundinidae, Motacillidae, Sturnidae, Corvidae, Turdidae, Paridae, Passeridae, Fringillidae, and Emberizidae. All recorded mammal species belonged to Rodentia, represented by the families Gliridae, Cricetidae, Gerbillidae, and Muridae. Most of these species are closely related to human activities, including obligate and facultative synanthropes (23 species) successfully adapted to anthropogenic landscapes. There are also pseudosynanthropes (6 species) that occur in populated areas but are not directly dependent on humans. The analysis showed that synanthropic species cause considerable damage to urban agriculture, infrastructure, and utilities. Major impacts include crop destruction, deterioration of monuments, damage to networks, and disease transmission. Special attention was paid to Meriones libycus, Ellobius tancrei, and Dryomys nitedula, recently identified as synanthropic species in Kyrgyz cities. Their inclusion provides new insights into urban ecosystem dynamics. The study proposes integrated control measures, including mechanical, chemical, and biological methods for effective management of bio-damaging species.

Birds play vital roles in ecosystems, including pollination, seed dispersal and pest control. Assemblages of bird species can serve as indicators of ecosystem services, making information on bird species composition crucial for developing effective conservation strategies in specific geographical areas. This study investigates the avifaunal diversity in the Purba Medinipur district of West Bengal, India, highlighting the ecological significance of bird species in coastal ecosystems. Conducted across 13 study sites from January to June 2024, the study recorded 102 bird species belonging to 16 orders and 39 families. The species composition included 55 resident and 47 migrant species, with Scolopacidae being the most abundant family. Dietary analysis revealed insectivores (34 species) as the dominant group, followed by omnivores and piscivores (17 species each). The IUCN status of the recorded species showed 94 as Least Concern, one Endangered, four Near Threatened, and three Vulnerable. Alpha diversity analysis using Shannon, Pielou’s Evenness, and Simpson’s Diversity indices showed varying levels of diversity across locations. The study emphasizes the importance of conservation and management of coastal ecosystems to protect the region’s rich avifaunal diversity, addressing specific conservation challenges in the area.

ABSTRACTAgricultural intensification and land reclamation have transformed natural wetlands into farmland across East Asia, which has been a threat to bird diversity, particularly wetland and grassland specialists. Despite extensive research in warm temperate and tropical rice‐growing regions, bird communities in snow‐rich agricultural wetland landscapes remain poorly studied. Here we present a dataset describing bird assemblages in a heterogeneous agricultural landscape surrounding Lake Kahokugata, located in a snow‐rich region on the Sea of Japan side of central Japan. The area represents a land reclamation zone shaped by decades of wetland conversion. We conducted point‐count surveys across 43 plots in winter and summer (2021 and 2023), yielding 129 replicated observations. The plots encompassed diverse cropland types, including rice paddies, lotus root fields, vegetable fields, pastures, and abandoned lands, representing a mosaic of wet and dry farmland. The dataset includes abundance records of 41 bird species, along with land‐use attributes within a 75 m radius and landscape data on open waterbodies within a 500 m radius. Our data is useful in providing insights into how landscape heterogeneity, cropland composition, and seasonal dynamics influence bird diversity in snowy agricultural wetlands.

This article is dedicated to the distinguished Ukrainian scientist Mykola Vasylovych Sharleman (1887–1970), who worked as a research associate at the Zoological Museum of the All-Ukrainian Academy of Sciences from 1921 to 1934 and held managerial positions at this institution in 1934(33)–1937 and 1941–1943. The long-standing scientific contributions of M. V. Sharleman provided the foundation for a collection that covers various regions of Ukraine and offers a valuable resource for analysing changes in the species composition and distribution of birds across Ukraine over the past century. A key milestone in this study was the discovery of the First Inventory Book of the collection from 1919, along with historical journals revised approximately in 1948–1949 that served as the collection’s catalogue. These unique documents proved to be vital in researching the history of acquisitions for the collections of the National Museum of Natural History of the National Academy of Sciences of Ukraine. Between 1907 and 1939, as well as in 1943, M. V. Sharleman donated 538 bird skins to the museum, representing 130 species of 13 orders. The most abundant specimens represented the species Calidris alpina (51 specimens), Phylomachus pugnax (28), Motacilla flava (26), and Dendrocopos major (19). Additionally, rare bird species listed in the Red Book of Ukraine were also present in the collection, such as Asio flammeus (2), Anarhynchus alexandrinus (1), Charadrius hiaticula (8), Columba oenas (1), Dendrocopos leucotos (4), Falco naumanni (2), Glareola nordmanni (2), Haematopus ostralegus (1), Lanius excubitor (2), Limosa limosa (2), Milvus migrans (1), Monticola saxatilis (1), Numenius arquata (2), Recurvirostra avosetta (2), and Sternula albifrons (3). The primary objective of this work is to study and promote the unique ornithological collection of the National Museum of Natural History (NMNH), which is the largest in Ukraine, encompassing over 40 000 specimens of 950 bird species. In addition to the scientific collection, which comprises bird skins (36 528 storage units) and egg clutches (2 998 units), there is also an impressive exhibition consisting of 1449 units. With its broad scale and scientific importance, this assemblage serves as a unique resource for biodiversity research. The ornithological collection holds not only scientific and cultural significance but also stands as a testament of dedication to the scientists whose meticulous work ensured its formation.

Bird diversity and composition is key for environmental assessments and conservation planning. Bird diversity associated with arid ecosystems has received substantial research interest worldwide. However, bird communities in the arid areas of Patagonia have been scarcely examined. In this study, we analyze the richness, abundance, and composition of bird species along a transect from the Andes to the Atlantic coast in northern Patagonia associated with two arid ecoregions—the Monte and the Patagonian steppe. We established 14 sampling stations along Route 23. A total of 14 bird surveys were conducted at each station between 1998 and 2012. We examined variations in bird community composition across 14 stations using distance-based redundancy analysis (dbRDA) including the environmental variables of mean temperature, annual precipitation, the presence of trees (associated with ranch houses), and water availability (categorized as permanent, temporary, or absent). A total of 126 bird species belonging to 20 orders and 38 families were recorded at the sampling points. We found that mean temperature and water availability play a key role in structuring avian communities in arid ecosystems. Given the ongoing challenges posed by global warming in the region, including severe droughts, these findings highlight the importance of establishing a baseline for future studies. Such data are crucial for developing management plans aimed at preserving bird diversity in these vulnerable ecosystems.

Abstract Fires pose an increasing threat to tropical forests worldwide. However, few studies have attempted to evaluate their impacts on bird communities. Consequently, the responses of tropical birds to this disturbance remain unclear. We assessed bird community composition, species richness and functional diversity between unburned and burned forests across 15 landscapes in the Brazilian Atlantic Forest. Additionally, we analysed how these indices were influenced by native forest cover, vegetation productivity, fire severity and fire size. To address these questions, we applied generalised linear mixed models. While unburned and burned forests exhibited similar species richness and functional diversity, they differed significantly in bird species composition. Species richness was positively associated with vegetation productivity. Functional diversity was primarily explained by fire size, with the magnitude and direction of the effects varying according to the functional index used and the forest type. Functional divergence showed a positive correlation with fire size in unburned forests and a negative correlation in burned forests. Functional dispersion, when considering communities across both forest types, was negatively correlated with fire size. Synthesis and applications. This study highlights how bird communities in the Atlantic Forest respond to fires. Our findings show that fire can significantly alter species composition, even when species richness remains unchanged. Bird community responses are further shaped by vegetation productivity and fire size, emphasizing the need to consider multiple ecological factors in post‐fire conservation strategies. We emphasize the need for tailored fire management strategies aimed at reducing forest degradation and fire occurrence. Effective measures, such as forest restoration and the implementation of ‘fire‐smart management’ practices, are essential to safeguard bird diversity. These results underscore the need for proactive governmental policies to prevent and manage fires in the Atlantic Forest, particularly in highly degraded landscapes.

The Brazilian Araucaria Forest (AF) now covers only 1% of its original extent due to significant degradation, making conservation a challenge. The AF occurs in a mosaic alongside grassland and Atlantic Forest ecosystems, influencing bird species’ distribution through ecological processes. We compared the composition and functional diversity of the bird community along a gradient of AF cover in a protected area (Pró-Mata Private Natural Heritage Reserve) in southern Brazil. Bird sampling was conducted using MacKinnon lists along five trails with different histories of vegetation suppression, based on forest cover estimates from landscape imagery. Birds were functionally classified based on morphological and ecological traits. We recorded 191 bird species in total. We found higher bird richness in trails with less forest cover, while functional diversity responded inversely to vegetation cover. Bird species composition shifted from more open-habitat specialists to more forest specialists with the increasing forest cover and vegetation structural complexity. These findings highlight the ecological importance of maintaining vegetation heterogeneity, as vegetation mosaics enhance avian species richness and support a broader range of functional traits and ecosystem processes. We recommend the conservation of Araucaria Forest–grassland mosaics as a strategic approach to support multidimensional biodiversity and sustain key ecological functions in southern Brazil.

Urban vacant land can provide important habitat for birds, especially in cities with high concentrations of residential vacancy. Understanding which vegetation features best support urban biodiversity can inform greening strategies that benefit both wildlife and residents. This study addressed two questions: (1) How does bird species composition reflect the potential conservation value of these neighborhoods? (2) Which vegetation structures predict bird abundance across a fine-grained urban landscape? To answer these questions, we conducted avian and vegetation surveys across 100 one-hectare plots in St. Louis, Missouri, USA. These surveys showed that species richness was positively associated with canopy cover (β = 0.32, p = 0.003). Canopy cover was also the strongest predictor of American Robin (Turdus migratorius) and Northern Cardinal (Cardinalis cardinalis) abundance (β = 1.9 for both species). In contrast, impervious surfaces and abandoned buildings were associated with generalist species. European Starling (Sturnus vulgaris) abundance was strongly and positively correlated with NMS Axis 1 (r = 0.878), while Chimney Swift (Chaetura pelagica) abundance was negatively correlated (r = −0.728). These findings underscore the significance of strategic habitat management in promoting urban biodiversity and addressing ecological challenges within urban landscapes. They also emphasize the importance of integrating biodiversity goals into urban planning policies to ensure sustainable and equitable development.

Abstract. The species composition and activity of birds in urban ecosystems largely depend on the level of anthropogenic impact, vegetation structure, and the availability of nesting sites and vary depending on landscape characteristics. Our analysis of the bird communities revealed that the large areas and diverse natural conditions provided higher species diversity compared with smaller areas with a high level of urbanization. This study analyzed the species composition of birds in garden squares and parks of the city of Dnipro and identified the features of their spatial distribution depending on the biotopes of the area. The research results indicate that the most active species were Columba livia, Sturnus vulgaris, Parus major, Passer montanus, and Turdus pilaris. The analysis of ecological groups of birds in the studied areas was conducted according to the M. Akimov’s system, considering the nesting characteristics of different bird species. The birds recorded in the city parks may indicate the presence of favorable conditions in the studied areas, although not all of them nested directly within park boundaries. The garden squares and parks with diverse biotopes and adjacent natural areas promoted higher bird activity and species richness, creating optimal conditions for the existence of bird species of different nesting types. Among the 13 identified bird groups based on nesting type, the most active were the "anthropogenic-substrate", "hollow-nesting, anthropogenic-substrate", and "tree-canopy" groups. In the parks, the least active groups of birds by nesting type were the "tree-canopy, anthropogenic-substrate" and "riparian". The greatest diversity of groups of birds by nesting type was recorded in the Diivkski Plavni floodplains. The presence of two-layered forest stands with a diverse composition of trees contributed to a higher number of bird species. Landscape diversity, such as the presence of sandy or clay cliffs and water bodies, created favorable conditions even for bird groups of specific nesting types, with low species richness. Urbanized areas located near the garden squares and parks served as important biodiversity hotspots, as they integrated anthropogenic and natural environments, providing nesting sites for various forest, synanthropic, and waterfowl species

ABSTRACTUnderstanding bird diversity and composition is important for assessing survival, adaptability, and extinction risks. This study investigated bird species abundance, richness, seasonal diversity, and composition across habitats, seasons, and physiographic zones of Chitwan Annapurna Landscape (CHAL) from 2020 to 2021 using the point count method. We recorded 458 bird species with higher richness and diversity in winter (n = 365) than in summer (n = 299). This study indicates a high diversity of birds (Shannon = 5.54, Simpson = 0.99) and an even distribution of species Pielou's Evenness Index (0.90). Species richness and abundance showed seasonal and habitat‐specific variations, with wetlands highest in winter (richness: 6.94 ± 0.38, abundance: 23.10 ± 5.65) and croplands in summer (richness: 7.00 ± 0.35, abundance: 13.61 ± 1.10), while forests exhibited stability. Evenness was high across all habitats (0.90 ± 0.01 to 0.95 ± 0.00), with minimal seasonal variation. Diversity indices were highest in cropland during summer (Margalef: 2.33 ± 0.10, Shannon: 1.77 ± 0.06, Simpson: 0.80 ± 0.02) and wetlands during winter (Margalef: 2.19 ± 0.08, Shannon: 1.75 ± 0.05, Simpson: 0.79 ± 0.01); forests had moderate and stable diversity, while grasslands showed low values. We observed 2 globally vulnerable, 5 near‐threatened, 2 endangered, and 3 critically endangered species. Analysis of similarity (ANOSIM) revealed significant community differentiation (p < 0.01) across parameters, with the strongest segregation in physiographic (R = 0.09), followed by seasons (R = 0.06) and habitat types (R = 0.01). Canonical Correspondence Analysis (CCA) showed distinct habitat clusters and a strong influence of physiographic zones, with winter and wetland habitats driving species variance. This study revealed substantial differences in bird species across seasons, and each habitat offers a distinct ecological niche for bird species. This finding highlights CHAL as a hotspot for bird community. This research contributes to the conservation and management of this landscape, aiding in the protection of bird species in Nepal.

Oak–lime–hornbeam forests are among the most biodiverse temperate forests. This study compared older managed stands with a strictly protected old-growth forest in terms of their features. Managed forests at various stages of silvicultural operations were selected: a mature stand where regeneration cuts had not yet begun, as well as stands where such treatments were in the initial or advanced stages. Stand features that may affect the diversity and density of avifauna were analyzed on the basis of 151 sample plots. In four successive breeding seasons, birds in these stands were surveyed. The stands differed significantly in volume, the density of large trees, regeneration, the vertical structure, and the amount of deadwood. The number of bird species was the highest in the initial and advanced gap-cut stands. Group-selection cutting in those stands led to a succession of non-forest bird species and, hence, a greater number of birds building nests on or close to ground as compared to the old-growth forest. The old-growth forest was the most similar to the mature managed stand in terms of bird species composition (Jaccard index = 0.76). The old-growth forest was characterized by the highest bird density (91 pairs per 10 ha), with more than half of the breeding pairs being cavity nesters. In the managed forest, the bird density was from 63 to 72 pairs per 10 ha. Based on the present study, it can be concluded that effective conservation of bird assemblages is possible in managed forests, provided that certain concessions are made. Drawing on the characteristics of old-growth forests, several guidelines can be proposed for forest management. First and foremost, it is essential to maintain a mosaic forest structure. Secondly, it is necessary to retain an adequate number of large, old trees within the stand and to ensure a sufficient volume and diversity of deadwood. Additionally, it is absolutely critical to shift timber harvesting activities outside of the bird breeding season.

The increasing prevalence of anthropized landscapes, often characterized by extensive agricultural practices and artificial infrastructure developments (e.g. wind farms), can lead to complex ecological scenarios where the functional roles of species within their communities are altered. This study aims to compare bird populations at two anthropized sites (Stipa and Sureste, Mexico) over a four-year period. Given their proximity (&lt; 5 km) and the shared characteristic of being located within wind farm areas on agricultural ground, similarities in bird species composition were expected. During the study, 88,765 birds of 178 species were recorded. The results revealed comparable species richness at both sites, with 137 species observed at Stipa and 135 at Sureste. Differences in assemblage composition were significant between sites and seasons (fall vs. summer, fall vs. spring), but not between years. The dissimilarity between the two sites seems to be mainly influenced by the presence of waterbirds associated with an irrigation canal at Stipa and raptors associated with open areas at Sureste, likely a favourable habitat to maximize hunting success. The stable species assemblage structure observed over the study years suggests constant resource availability resulting from habitat homogenization driven by expanded sorghum cultivation displacing other crops. Conversely, variations in bird composition between seasons were influenced by migratory patterns, particularly among raptors, which became more abundant over the study years. This study supports the idea that artificial water supplies can favour the presence of bird species with an affinity for aquatic habitats in anthropized habitats, such as at Stipa. This highlights the importance of designing, regulating and well-managing artificial resources in anthropized landscapes, as these can contribute to habitat restoration, increase taxonomic diversity, and help achieve long-term conservation goals.

ABSTRACT Increasing temporal and spatial coverage of bird inventories is urgent in changing tropical ecosystems. Camera trapping, traditionally focused on surveying mammals, has been pointed out as a potential tool to complement standard bird surveys. However, few standard bird surveys and camera trapping comparisons have been made in tropical biodiversity hotspots. We conducted camera trapping and point count surveys of bird species in eighteen 1 km2 landscape units along a deforestation gradient in the Lacandon forest in México. We compared the two methods based on the estimates they produced of bird species richness, composition, body mass, and conservation status. We recorded 2.6 times more species by point counts than by camera trapping. There was no correlation between the number of species recorded by the two methods, and the similarity in species composition was low. Body mass was higher in species recorded by camera trapping only in medium levels of deforestation. Camera trapping has little potential to replace standard bird survey methods, such as point counts, for documenting bird species diversity. However, in some circumstances, it can be a valuable tool to help document the presence of some bird species by monitoring them throughout the day.

The 2014−2016 Pacific marine heatwave (PMH) was an intense and prolonged environmental disturbance that significantly disrupted the marine food web, leading to widespread ecological impacts. The PMH contributed to major shifts in species distributions, mass mortalities, and reproductive failures among upper-trophic level species, including a massive die-off of common murres (Uria aalge) in the Gulf of Alaska (GOA). To assess the impact of the PMH on the winter marine bird community in Prince William Sound (PWS), a large embayment in the northern GOA, we analyzed changes in winter marine bird abundance and species composition in a series of bays before and after the PMH. The overall density of winter marine birds decreased and species composition significantly changed in PWS following the PMH. Specifically, common murres, cormorants, and loons decreased from pre-PMH survey densities, while marbled murrelet (Brachyramphus marmoratus) densities increased. The post-PMH increase in marbled murrelets, likely due to immigration, coincided with the rapid growth and spatial expansion in the PWS Pacific herring (Clupea pallasii) young-of-the-year population and with a smaller, 8-month marine heatwave across the northern GOA. We suggest the mass mortality and lack of recovery by the common murre population provided a competitive release enabling murrelets to exploit a growing forage fish population, and that murrelets may be more effective at shifting to warmer-water zooplankton during marine heatwave events. These results highlight the persistent upper-trophic level changes associated with the PMH and provide important insights into the ecological consequences of environmental disturbances. This is increasingly relevant given the predicted increase in frequency and intensity of marine heatwaves.