Introduction: Birds (Class Aves) are one of the most varied categories of vertebrates with over 9,000 species found on the planet and able to inhabit vastly different environments. They are important ecologically, as they are involved in seed dispersal, pollination and scavenging, and as biological control of harmful insects, small vertebrates as well as having economic value as providers of animal protein to humans in many areas. Birds due to their mobility and various habitats act as hosts to a wide range of parasites and especially the ectoparasites which can have a major impact on the health, survival and reproductive success. Methods: In this study, chewing lice infestation was studied in Dunlin birds (Calidris alpina) found in various locations in the Al-Diwaniyah Province of Iraq where 54 birds were collected between September 2023 and April 2024. Results: Five species of chewing lice were isolated and identified after careful examination, they include: Actornithophilus umbrinus (35.18%), Austromenopon alpinum (29.62%), Carduiceps sp. (24.07%), Lunaceps actophilus (24.07%), and Lunaceps drosti (16.66%). One hundred and forty infested birds were identified totaling 62.96 infestation rate. There was a statistically significant difference between male and female birds (P≤0.05), with the male having a higher infestation rate (72.41%) than females (52%). Infestation pattern analysis showed that there was a significant difference (P 0.05) in patterns of infestation with single infestation being the most common (76.47%), then followed by double (50) and triple infestations (20.58). Conclusion: The results of the current paper are the initial record of chewing lice species infesting Calidris alpina in Iraq. These findings add a useful contribution to the literature on the avian ectoparasite in migratory birds and underscore the role of gender of the host and ecological conditions on dynamics of infestation. Surveillance of migratory birds is also advisable to get a clearer insight into host-parasite interactions and patterns of chewing-lice species distribution in the area.

Forests play a crucial role in maintaining terrestrial ecological diversity. In this study, two distinct forest types—built environments (Forest Reserve 27) and regenerated forests (Lusaka National Park)—in Lusaka, Zambia, are compared with respect to their bird species diversity and concentration. Predicting the bird species' preferred sub-habitat structure is another objective of this study. To evaluate species richness and species diversity, two ecological indicator indices were employed: The Simpson's Diversity Index (D) and the Shannon-Weiner Diversity Index (H'). Eight days in all, four days at each site, were dedicated to gathering data. To acquire data, an analytical experimental strategy utilizing transect formulation, geo-referencing, and mapping in a naturalistic observational study. In addition, the International Union for Conservation of Nature red list categories were examined, order categorization, diet, habitat type, and migration status. Forest 27 and Lusaka National Park yielded a total of 241 individual bird sightings. These totaled 79 observations, of which 35 (at 95% confidence interval 33.6-45.6%) came from Forest 27 and 44 (55.7%) from Lusaka National Park (95% confidence interval 44.4 – 66.4%). The species richness and species diversity of Lusaka National Park were measured at H' = 3.5 and D = 28.5, respectively, whereas Forest 27 saw H' = 3.2 and D = 23.1 for species richness and diversity, respectively. Although they highlight different facets, Simpson's and Shannon-Wiener diversity indices both quantify biodiversity. While Shannon-Wiener takes into account both richness and evenness, with higher values suggesting higher diversity, Simpson's concentrates on dominance, with higher values indicating lower diversity. It was concluded that a variety of variables, including climate, fragmentation, noise pollution, affecting Forest 27 are probably responsible for Lusaka National Park's greater species richness and diversity. This covers government policies on the forest reserve: 1. Sustainable use – Utilization of forest resources in a sustainable manner must be the focus as well as balancing wood extraction with the preservation of ecosystem services such as biodiversity conservation and carbon sequestration. 2. Biodiversity Protection- forest reserves are designed for the safeguard of threatened species and important ecosystems. In regards to forest reserves and protected areas, policy re-evaluation would be advised. Conservation strategies should focus on a variety of ground-nesting, canopy nesting and insectivorous bird species that are negatively impacted by logging. Conducting another assessment a few years from now would be recommended to further conclude whether Lusaka National Park would still compete or hold a higher amount of diversity and abundance compared to forest 27or other forest reserves in the Lusaka area.

Abstract Modern birds inhabit a remarkable breadth of ecological niches, a diversity that is in part attributable to the range of forms and functions that have evolved in the avian foot. Variation in the lengths, orientations, and internal proportions of their toes have enabled specialised grasping, climbing, and walking morphologies to evolve from a shared ancestral form. However, many individual elements of the foot are developmentally moderated in tandem. This integration of phenotypic traits can benefit the evolutionary process by coordinating traits to better maintain complex functions across generations, but may also inhibit adaptation in individual traits. Hence, trait integration has the capacity to constrain or enable evolution in certain directions. Here, we examine how adaptation for grasping (i.e., perching, climbing, and object manipulation) affects strength of integration in four common avian foot morphologies. Using measures of trait covariation and correlation, we conclude that grasping ability alone is likely an insufficient predictor of morphological integration. Overall, whole-foot integration strength and evolutionary potential are surprisingly consistent across the sampled morphologies, however, there exist differences in fine-scale integration patterns across species that merit further investigation. We find anisodactyl foot morphologies (e.g., fowl and songbirds) appear less integrated and more evolutionarily flexible than zygodactyl morphologies (e.g., parrots and woodpeckers), but that zygodactyl morphologies may be capable of a greater response to selection in certain directions. Such research helps to inform our understanding of both the evolutionary history of these taxa as well as how they may adapt to changing ecosystems in the future.

Machine learning holds great promise for classifying and identifying fossils, and has recently been marshaled to identify trackmakers of dinosaur footprints and address long-standing debates over whether some dinosaur tracks are the oldest birds or ornithopods (duck-billed herbivores and kin) in the fossil record, or alternatively were made by nonavian theropods. Existing methods in paleontology, however, require supervision and a priori labeling of training data by researchers, which can lead to bias. We employ an unsupervised machine learning technique for recognizing inherent patterns in shape data, using a disentangled variational autoencoder network, to a database of 1,974 footprints, spanning a diversity of dinosaurs across their evolutionary history, including modern birds. Our neural network identified eight features of shape variation that most differentiate these tracks: overall load and shape (amount of ground contact area), digit spread, digit attachment, heel load, digit and heel emphasis, loading position, heel position, and left-right load. With the unsupervised process finished, we a posteriori labeled each track based on published expert judgments, plotted them into morphospace, and applied distance metrics to group means and nearest neighbors, which showed 80 to 93% agreement with expert identifications. Controversial Late Triassic-Early Jurassic bird-like tracks group with fossil and modern birds and some Middle Jurassic three-toed tracks with ornithopods, supporting an older origin for these groups than recorded by body fossils. We provide an app, DinoTracker, to make this process accessible, and source code that can be adapted to other cases where paleontologists or biologists are studying patterns of shape variation.

When modern birds engage in powered flight by flapping their wings, the upstroke movement is produced mainly by a ventrally located muscle called the musculus (m.) supracoracoideus. To achieve this unique mechanism for elevating the humerus, birds have evolved the triosseal canal, a tunnel-like structure which deflects the tendon of the m. supracoracoideus. This canal comprises bony projections of three different skeletal elements of the pectoral girdle (i.e., scapula, coracoid, and clavicle). Importantly, the acrocoracoid process of the coracoid structurally constitutes an essential component for the realization of the triosseal canal's function. Consequently, it has been identified as a key morphological feature for flapping in modern birds. Although limb and girdle development has been extensively studied using avian embryos, the morphogenesis of the avian coracoid itself remains poorly described. To address this knowledge gap, we performed morphological and histological analyses of the shoulder musculoskeletal system of the avian embryo, focusing on the development of the acrocoracoid process. We found that the acrocoracoid process emerges during embryonic development as a lateral protrusion of the dorsal coracoid. Meanwhile, the tendon of the m. supracoracoideus elongates laterally. Using histological analysis, we demonstrate that several shoulder and limb muscles, including the mm. biceps brachii, coracobrachialis, and deltoideus minor, attach to the acrocoracoid process during its development. Our results provide the first detailed description of the ontogenic development of the acrocoracoid process.

Purpose : The aim of the study was to determine the efficiency of the freezing protocol for day-old chick ovaries depending on the composition of the cryoprotective medium. Materials and Methods . Russian Snow White chickens (n=30) were used to obtain the ovaries of day-old chicks. Freezing was performed using a simple two-stage vitrification method, using DPBS-based cryoprotective media containing dimethyl sulfoxide, ethylene glycol, and sucrose as cryoprotectants in the control (medium A) and the addition of inositol (0.5 M) (medium B) in an experimental modification of the cryoprotective medium. The effectiveness was assessed after in vitro storage at -196°C for 30 days, based on the condition of primary follicles in histological samples. Results . Data were obtained based on the results of evaluating histological samples for the integrity of oogonia in the cortex of thawed ovaries: when using cryoprotective medium A, the number of morphologically intact oogonia was 1,4 pcs. per field of view (magnification x400), which was 5,4 % of the indicator for native samples; when using medium B — 9,0 pcs. oogonia (34,5 % of native). Conclusion. The creation of a long-term cryobank for the storage of female gametes of the avian class (Aves) is a relevant strategic solution to the problem of preserving the genetic diversity of breeds and species. The efficiency of gonadal tissue freezing depends on the chosen donor age and the cryopreservation protocol, taking into account the composition of the cryoprotective media. The presented data prove the effectiveness of the protocol for freezing the ovaries of day-old chicks using a cryoprotective medium containing inositol (medium B) allows preserving a significant percentage of morphologically intact ovarian tissue structures and, directly, the oogonia in it.

ABSTRACT Motivation The role of each animal species in an ecosystem is largely determined both by the resources it uses and the behaviours through which these resources are obtained. Even in well‐studied vertebrate groups, like birds, quantitative data on the relative use of different food resources in the context of foraging strategies are generally lacking. Most analyses in macroecology, macroevolution and conservation biology are therefore limited to simplified dietary categories, ignoring the specific foraging behaviours and substrates used to access resources. Here we present AVONICHE, a dataset quantifying proportional membership in 32 foraging niches, representing a combination of dietary categories and associated foraging strategies used by all bird species. Main Types of Variables Contained Species‐level information on the proportional use of foraging niches, each of which is defined as a particular foraging strategy within a specific dietary category (e.g., invertebrate feeding is subdivided into 7 foraging niches based on different foraging behaviors). Spatial Location and Grain Global. Time Period and Grain Present. Major Taxa and Level of Measurement All bird species (Class Aves). To allow integration with global phylogenies and other data resources published in future, we align species‐level niche data with four different taxonomic treatments: BirdTree (9993 species), Clements/eBird (10,661 species), BirdLife International (10,999 species) and the new AviList taxonomy (10,981 species). Software Format Spreadsheet (.csv).

The Red-legged Partridge (Alectoris rufa, Phasianidae) is a non-migrant gamebird endemic to southwestern Europe that was introduced into Mediterranean and Atlantic islands in historical times. This is the case for Madeira, Portugal, where a population morphologically assigned to A. r. hispanica has been present since the XV century. We assessed its genetic identity using 2248 (Cytochrome-b, Cyt-b + Control Region, CR) and 297 bp-long (CR) mitochondrial DNA sequences obtained from modern and archival (1900–1964, including Caccabis rufa maderensis syntypes) partridges, respectively. These sequences were compared against an already published dataset covering the entire Iberian A. rufa range. We found that all the haplotypes of modern birds from Madeira were private to this island. The putative subspecies was confirmed, and northern Portugal with northwestern Spain turned out to host the closest mainland populations. This result was in line with the origin of the first human settlers of Madeira from, among other historical provinces, Douro Litoral and Minho, the latter neighboring Galicia. Despite relatively recent A. rufa importations from continental Europe, we did not find any significant change over time in the haplotypic pattern of Madeiran partridges as well as any evidence for maternal introgression from species such as the congeneric Chukar Partridge (A. chukar). Studies relying on genome-wide markers and including the only captive-bred population of Madeira are needed to gain more comprehensive information for the management of the local A. rufa.

Mistletoes occur worldwide, with most relying on birds to disperse their sticky seeds to suitable hosts. There has been considerable ecological research on these interactions, emphasizing those birds dependent on mistletoe fruit as their principal food source, but the origins and evolutionary trajectories of these dietary specialists have rarely been considered. Of the ten lineages of mistletoe fruit specialists, five are from the Tyrannida infraorder of South American songbirds comprising mannakins, cotingas, tyrant flycatchers and allies. Integrating current understanding of early songbird evolution with available dietary information, two sets of findings emerged. First; dependence on mistletoe fruit is conserved over time, with strong evidence that the 137 mistletoe‐dependent species in ten groups scattered among Neotropical suboscines arose from a rapid radiation in the late Oligocene and early Miocene. Although interpreted as a single origin of mistletoe fruit dependency, the degree of dependence was dynamic, mistletoe fruit specialists evolving from more generalised mistletoe‐dependent lineages on five separate occasions as they radiated into the Americas from Gondwanan connections. Second, variation in diversity of modern mistletoe specialist frugivores can be explained by lineage age, older lineages consistently less diverse. Considering both representatives from the Neotropical groups evaluated here and the other five families across modern birds, mistletoe fruit specialists initially spread rapidly, colonising new areas and speciating, then eventually becoming restricted to single regions represented by relictual lineages with divergent morphologies. After exploring the historic basis, evolutionary implications and ecological relevance of these findings, I consider alternative explanations and articulate testable predictions to test these inferences and guide future work.

ABSTRACT The application of artificial intelligence is gaining traction in the study of cultural ecosystem services (CESs). In response to this trend, we have developed an approach based on photo categorisation and semantic segmentation to assess CESs, including aesthetic values in riverscapes and river elements (large wood, erosion banks and river bars). Semantic segmentation allows the precise identification of photos, including quantification of features coverage. To validate our approach, we chose the riverscape of the Odra River in the Czech Republic, a smaller but significant site protected under the Ramsar Convention and Natura 2000. Our goal was to understand the content of the photographs and to delineate the categories of CESs present in this region. We demonstrated the efficacy of our approach and found that our manual categorisation of publicly available photos from Google Maps and Flickr revealed a consistent trend: visitors predominantly took photos from the river and pond and urban categories. CESs presented in the area include outdoor recreation, bird watching, education and hiking. Semantic segmentation analysis revealed that the photographs primarily depicted water, vegetation types and sky, while the river elements in the photographs were of minimal size. Our results highlight the need for improved visitor education about riverscapes, including river elements defined as important hydromorphological parts of the river. Our method does not require extensive programming knowledge, making it suitable for river managers. This approach allows for better monitoring of important riverscape features, which may contribute to more effective river protection.

Birds play an important role in ecosystem as pollinators and seed dispersers, so avian diversity can serve as an indicator of environmental quality. This study was at Muaro Jambi Temple, a National Cultural Heritage Area (KCBN), and began with a presentation on observation techniques, field identification, and understanding of ecological characteristics. The survey was conducted in two observation zones, namely the core zone and the buffer zone, using the point count method. Observers stood at specific points within the habitat and recorded bird sightings during defined time periods. Observations were conducted for one week in August 2025, from 6:00 a.m. to 9:00 a.m. and 3:00 p.m. to 6:00 p.m. The study recorded 79 species comprising a total of 327 individual birds. The Shannon-Wiener diversity index (H’) of 3.75 indicates a very high level of diversity in the area. Several species found are protected, including frugivorous and pollinating birds. Based on the IUCN Red List, identified species include the Java Sparrow (Vulnerable), the Ciblek/Perenjak (Near Threatened), and a numerous other species categorized as Least Concern. These findings emphasize the importance of conservation efforts at KCBN Muaro Jambi to preserve habitats and maintain the ecological function of birds.

Origin and diversification of Dicrocoeliidae (Neodermata, Trematoda) with the description of a new species of Euparadistomum, a parasite of Tropidurus torquatus (Squamata, Tropiduridae) in South America.

Abstract This contribution identifies biogenic structures created by modern birds foraging in marginal aquatic settings and provides descriptions to facilitate their identification in the rock record. Biogenic structures related to foraging can be separated into those created by bills, such as peck marks, probe marks, gape marks, dabble marks, sweep marks, and bill-stir marks. Biogenic structures created by feet include stir tracks and paddle pits. Peck marks are created during visual foraging and result in shallow, solitary or paired, random or clustered, circular to subcircular pits and grooves. Probe marks are created during tactile foraging but are similar to peck marks, differing solely in their greater depth of penetration. Gape marks are formed when birds open their bill in the sediment resulting in elongated grooves. Dabble marks are larger ovoid divots emplaced by broad-billed waterbirds in subaqueous settings. Bill stirring occurs when a bird swishes its bill in a narrow trend on the sediment surface. Sweep marks are arcuate grooves emplaced in the sediment when long-billed birds forage by sweeping their bill side-to-side across the sediment–water interface.Birds shuffling their feet in soft sediment is termed ‘foot-stirring’ and results in overprinted, side-by-side trackways. Foot-paddling dewaters the sediment and produces various pit morphologies with massive fill. Trackways emplaced during foraging are commonly characterized by variable stride length, stutter steps, and sudden changes in direction. ‘Trample grounds’ are produced by gregarious foraging flocks of birds. It is anticipated that illustrating and describing the structures produced by these behaviors will facilitate recognition of these commonly overlooked traces.

BackgroundAccurate assessments of changes in breeding bird populations require regular, structured surveys or, alternatively, carefully documented benchmarks that can be precisely repeated. We re-surveyed a historic benchmark of forest bird communities in Western Oregon, USA, originally conducted by Stanley Anderson between 1968-1970. Anderson’s thesis uniquely preserves detailed plot locations, species density estimates, vegetation structure summaries and methodological descriptions — an uncommon level of documentation for the time. To facilitate accurate comparisons and future re-surveys, we explain how we aligned our methods with Anderson’s and incorporated modern bird counting techniques. We also provide our raw data, metadata and methodological details to ensure transparency and reproducibility.New informationAnderson’s work presents unusually old and detailed datasets of forest bird communities preserved from the Pacific Northwest, USA. It provides a unique opportunity to examine long-term changes in breeding bird communities within these forested landscapes affected by anthropogenic influence. The data and methods presented here are well-documented, ensuring that this benchmark can be effectively used for precisely repeatable re-surveys and comparative studies.

Avian features of Archaeopteryx feeding apparatus reflect elevated demands of flight.

An enlarged sternum with a prominent keel is a central feature of the flight apparatus of modern birds. However, sterna of near-bird dinosaurs (Pennaraptora) and early avialans are either substantially different from those of living birds or absent altogether, raising questions about how specialized sternal structures evolved in birds and how they are related to function. This remains poorly understood because of the fragmentary nature of the fossil record, and the challenges in inferring form and function from crushed fossils. We use ancestral character estimations to trace sternal trait acquisition through the bird stem group, and multivariate phylogenetic regressions to analyse relationships between sternum morphology, body mass and flight capabilities. We find that sternum evolution was episodic: basal members of Pennaraptora had proportionally small sterna, which became larger and more craniocaudally elongated in Avialae. This enlargement precedes the appearance of a midline ridge, a possible precursor of the sternal keel, in Pygostylia. Sternum size increased again in crownward Ornithuromorpha, alongside a fully formed sternal keel and enlarged caudal projections, both critical areas of flight muscle attachment. Sternal experimentation in relation to flight characteristics occurs several times throughout Pennaraptora, including within Paraves and Enantiornithes, indicating that powered flight may have evolved several times before proliferating in crown-group birds.

Recent advances have deepened our understanding of the evolutionary and developmental origins of feather branching architectures. However, the internal tissue differentiation within these branches has received limited attention. This study examined eight fossilized feathers preserved in early Late Cretaceous Burmese amber, characterized by barb rami composed entirely of cortical tissue with no internal medulla. Based on barb rami morphology, the feathers were categorized into three distinct morphotypes. Comparative analysis with feather development in extant chickens suggested minimal tissue differentiation in these early feathers. Functional simulations further revealed that modern barb rami configurations provide greater aerodynamic stability than medulla-free early feathers under most conditions, highlighting flexural stiffness as a key factor in the evolution of feather branches. The presence of medulla-free barb rami suggests that although the three-level hierarchical branching pattern characteristic of modern feathers had emerged by the Jurassic, tissue differentiation within feather branches remained developmentally unstable during the Late Cretaceous. This instability likely contributed to the structural variability of early feathers, enabling morphologies that no longer persist in modern birds.

BackgroundMicroraptor is an essential animal for understanding the evolution of flight in birds and their closest relatives. Recent studies have uncovered evidence of its powered flight potential and details of its diet and ecology. However, we are still missing a thorough description of the anatomy of Microraptor connecting feathers, soft tissues, and osteology together. Here we focus on the forelimbs of ten new Microraptor specimens from the Shandong Tianyu Museum of Nature studied under Laser-Stimulated Fluorescence. We compared our results with extensively studied existing specimens (e.g., IVPP V13352 and BMNHC PH881), other key early paravians (e.g., Anchiornis, Archaeopteryx and Confuciusornis), as well as modern birds to expand what we know about flight origins, and early diverging paravian theropods more generally.ResultsPlumage was previously only minimally known. Reconstruction of the forewings relied on brief descriptions of the primary and secondary feathers. With the new specimens studied here, we uncovered the whole shape of the wing from the tip of the digits to the proximal end of the ulna, the different layers of feathers, and the number as well as characteristics of each feather type. Skeletal features of the forelimb remain mostly unchanged from previous descriptions, but we bring new information regarding wrist bones and functional implications of humerus and radius features. The most significant advances have been recovered in preserved soft tissues including those of the shoulder, propatagium and postpatagium. In particular, the new specimens of Microraptor help us to understand the impact of the soft tissues on lift generation and cohesiveness of the forewing.ConclusionsThis study permitted us to recreate the most accurate forewing of Microraptor to date. Taken together, new information on the forelimb anatomy shows that Microraptor shares many of the forewing characteristics of early avialans and modern birds, and helps us to better understand the flight behaviour and ecology of this iconic and unique ‘four-winged’ animal along with its role in flight evolution. These results serve as a starting point to conduct more precise and integrative analyses (e.g., including hindwings and/or tail) on the locomotor behaviours of Microraptor.

Monitoring of birds (Class Aves) through their vocalizations that potentially change over time has always been a challenging problem in bioacoustics. Machine learning methods have provided researchers in bioacoustics with many non-invasive ways to study vocalizations. For powerful methods like Hidden Markov Models (HMMs), the models have been deployed to study bird vocalizations but over a limited time period. Through the application of HMMs to Chiffchaff (Phylloscopus Collybita), Little Owl (Athene Noctua), and Tree Pipit (Anthus Trivialis), the three species of birds with varying degrees of complexity in their vocalizations and migration patterns are investigated during the same year and subsequent year. The models were able to successfully discriminate between the species of birds with recognition accuracies of 95.96% (Within-Year) and 96.74% (Across-Year) and demonstrate the feasibility of the long-term bioacoustics monitoring of migratory and non-migratory species using HMMs.

Summary Latin America boasts a distinct and rich natural and cultural heritage. The region, along with its individual countries and localities, features a mosaic of iconic destinations that cater to a wide range of travel experiences, ranging from generalized (e.g., sun, sand, and sea) to specialized (e.g., bird watching) interests. By drawing in specialized travelers – who often have higher purchasing power and tend to be more culturally and environmentally conscious – Latin America has gained recognition for its ecotourism, culinary tourism, experiential tourism, and other niche travel experiences, all of which highlight its diverse landscapes and heritage. However, agritourism in Latin America remains largely unacknowledged as a distinct travel segment despite its rich agricultural heritage, both tangible and intangible. This oversight is noteworthy given that the region is the cradle of many agricultural products that have become staple ingredients worldwide, such as potatoes, corn, and tomatoes. Alongside this agricultural wealth, Latin America offers a diverse repertoire of travel experiences that highlight unique practices, products, and lifestyles tied with its agricultural traditions. However, these experiences are seldom recognized or promoted as agritourism, missing an opportunity to leverage the region’s deep agricultural roots. The limited recognition of agritourism as a distinct brand in Latin America may stem from the region’s prevailing indigenous cosmovision, which views agriculture as an integral part of their livelihoods, thus often framed as experiential or heritage tourism. Alternatively, the region’s pride in local foods and beverages often leads to categorizing these activities under culinary tourism. Regardless of the reason, the absence of a clear and standalone identity for agritourism is limiting policy development, outreach, and advocacy efforts, thereby restricting the potential of a travel segment that brings substantial benefits to local producers, their communities, and overall society. Information © The Author 2025