Biotropica最新文献

{"title":"120 Years of “Lemurology”: What has Changed?","authors":"Veronarindra Ramananjato,&nbsp;Finaritra Randimbiarison,&nbsp;Seheno Andriantsaralaza,&nbsp;Anja R. S. Rafaharetana,&nbsp;Tanjoniaina H. N. P. Rabarijaonina,&nbsp;Hasinavalona Rakotoarisoa,&nbsp;N. Nancia Raoelinjanakolona,&nbsp;Diary N. Razafimandimby,&nbsp;Rindra H. Nantenaina,&nbsp;Njaratiana A. Raharinoro,&nbsp;Tsinjo S. A. Andriatiavina,&nbsp;Sandra M. Rasoarimalala,&nbsp;Harielle F. Ratianarinambinina,&nbsp;Mirana J. E. Rahariniaina,&nbsp;Onja H. Razafindratsima","doi":"10.1111/btp.70026","DOIUrl":"https://doi.org/10.1111/btp.70026","url":null,"abstract":"<p>Lemurs, a highly diverse primate group endemic to Madagascar, have captivated the attention of researchers for nearly 120 years. Here, we conducted a literature review and a bibliometric analysis to provide an overview of how various aspects of “Lemurology” or the scientific studies of lemurs, have changed over time. Focusing only on original scientific articles, we described the trends in the topics and taxa studied, the publication languages, the authorship, and study sites. We used two datasets: one from the Web of Science (WoS; 2223 articles) and another from three Madagascar-focused journals (MFJ; 329 articles). The observation of lemurs in the wild is the oldest form of Lemurology, starting under the French colonization, and remains the main data source for articles in both datasets. <i>Microcebus</i> and <i>Eulemur</i> are the most studied genera in WoS and <i>Propithecus</i> and <i>Eulemur</i> in MFJ. At this time, no articles are written in Malagasy, but English and French are the main languages used in Lemurology. Although Malagasy scientists are still underrepresented at the international level, there is a recent shift toward an increased number of Malagasy scientists as first and last authors. We found no gender bias in WoS, but MFJ exhibited noticeable male author dominance. Most Lemurology has been conducted at the Duke Lemur Center (USA), followed by Kirindy and Ranomafana forests in Madagascar. Lemurology thus shows different portraits at international and local levels, suggesting that unequal access to resources and opportunities may hinder the effective investigation and conservation of lemurs.</p>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/btp.70026","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143689416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Differences in Plant–Pollinator Network Structure and Pollinator Importance Between a Continental and an Oceanic Island Community","authors":"Xiang-Ping Wang,&nbsp;Ma-Yin Tong,&nbsp;Yu Zhang,&nbsp;Zhong-Tao Zhao,&nbsp;Shi-Jin Li,&nbsp;Miao-Miao Shi,&nbsp;Tie-Yao Tu","doi":"10.1111/btp.70027","DOIUrl":"https://doi.org/10.1111/btp.70027","url":null,"abstract":"<div>\u0000 \u0000 <p>Pollination is an important ecological process for plant reproduction. Understanding the differences in plant–pollinator interactions and pollinator importance across spatial scales is vital to determine the responses of these interactions to global changes. Continental and oceanic island systems provide us with an ideal model to examine the variation in plant–pollinator interactions. Here, we compared the differences in species composition, plant–pollinator network structure, and pollinator importance in communities between a continental island (Wanshan Island) and an oceanic island (Yongxing Island) in China. The results reveal highly dissimilar species composition between continental and oceanic islands that caused highly different plant–pollinator network structures. In particular, the oceanic island networks had higher network connectance, nestedness, and specialization than the continental island networks. For plants cooccurring on both islands, pollinator species richness and flower visitation rate were higher on the continental island than on the oceanic island. Plant niche overlap was higher on the oceanic island than on the continental island, while pollinator niche overlap was higher on the continental island than on the oceanic island in both the entire network and cooccurring plant species subnetwork. Hymenoptera was the most important pollinator group in the continental island community, while Apidae was the most important in the oceanic island community. The results imply that oceanic island communities may be less vulnerable to disturbance, such as habitat alteration or destruction, than continental island communities and provide implication insights into biodiversity conservation for pollinators on islands.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143689415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combining Climber Cutting and Tree Seedling Planting Improves Structural Attributes of a Seasonal Semideciduous Forest in Southeastern Brazil","authors":"Guilherme Aparecido Melo dos Santos,&nbsp;Valéria Forni Martins,&nbsp;Ana Carolina Cardoso de Oliveira,&nbsp;Marina Pérola Zerbinato José,&nbsp;Ricardo Augusto Gorne Viani","doi":"10.1111/btp.70023","DOIUrl":"https://doi.org/10.1111/btp.70023","url":null,"abstract":"<div>\u0000 \u0000 <p>Management of degraded tropical forest fragments is usually done by cutting climbers (cutting). However, it is still necessary to understand the outcomes of cutting in combination with planting native tree species' seedlings (cutting + planting), especially on the edges of fragments, which are subject to higher disturbance than the forest interior. We tested whether cutting + planting is the restoration strategy that most improves structural attributes of a degraded edge of a tropical seasonal semideciduous forest fragment in southeastern Brazil, relative to cutting and the absence of management (control). Linear mixed models revealed that, after an eight-year period, cutting + planting resulted in the highest decrease in the density and basal area of climbers longer than 1 m, and in the highest increase in the density of large living trees (diameter at breast height, DBH, ≥ 4.8 cm). Although cutting + planting decreased the percentage of large dead trees and increased tree sapling (DBH &lt; 4.8 cm and total height ≥ 50 cm) richness, these variables were more affected by cutting. Management had no effect on the basal area of large living trees and tree sapling density. Because most structural attributes of the degraded edge studied were improved by cutting + planting, we advocate that it is the best strategy tested here for restoring tropical seasonal forests. We hypothesize that seedling planting improves forest conditions and stimulates recruitment, facilitating the regeneration of tree species. Thus, an interesting future avenue is to elucidate the mechanisms by which seedling planting affects regeneration and its long-lasting effects on forest structural attributes.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143689326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of the Alternative Stable States Concept in Tropical Terrestrial Ecosystem Research—A Systematic Literature Review","authors":"Stella Mata,&nbsp;João Marcelo Alvarenga Braga,&nbsp;Bernardo M. Flores,&nbsp;Jerônimo Boelsums Barreto Sansevero","doi":"10.1111/btp.70025","DOIUrl":"https://doi.org/10.1111/btp.70025","url":null,"abstract":"<div>\u0000 \u0000 <p>Global changes can impact ecosystem resilience, leading to abrupt and irreversible shifts in structure and function. In the face of increasing anthropogenic disturbances, understanding mechanisms that destabilize ecosystems and push them into alternative stable states is crucial. We conducted a systematic review of the application of concepts from dynamic systems theory—alternative stable states, tipping points, hysteresis, and alternative pathways—in tropical terrestrial ecosystem research. We identified 135 articles (71 observational, 59 theoretical/modeling, four experimental, one meta-analysis) using these concepts, addressing ecosystem changes due to anthropogenic and natural disturbances. Most articles focused on conservation biology (46%), followed by climate change (31%), successional ecology (28%), ecological restoration (16%), physiology (15%), novel ecosystems (3%), and biological invasion (3%). Fire was the primary disturbance driving shifts into alternative stable states (54%). Disturbance roles varied across biomes. Numerous articles on tropical and subtropical broadleaf forests highlighted biodiversity and ecosystem service losses due to disturbances. Conversely, studies on tropical and subtropical grasslands, savannas, and shrublands emphasized fires and herbivory as key factors in the maintenance of the structure and composition of savannas. The high number of articles on these biomes underscores their importance. The review highlights that considering alternative stable states in the responses of ecosystems to global changes can enhance disturbance mitigation and ecological restoration, potentially averting future biodiversity and ecosystem service losses. Addressing ecosystem responses to global changes from this perspective can enable more effective disturbance mitigation and ecological restoration actions.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143689331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Linking Landscape Features, Anthropogenic Stressors, and Mammal Abundance to Unveil Seed Removal Patterns in Tropical Deforested Landscapes","authors":"Elaine Rios,&nbsp;José Carlos Morante-Filho,&nbsp;Maíra Benchimol,&nbsp;Kristel De Vleeschouwer,&nbsp;Marcelo Magioli,&nbsp;Ronaldo Gonçalves Morato,&nbsp;Eliana Cazetta","doi":"10.1111/btp.70024","DOIUrl":"https://doi.org/10.1111/btp.70024","url":null,"abstract":"<div>\u0000 \u0000 <p>Land-use changes and related anthropogenic pressures are responsible for biodiversity declines and threaten the provision of ecosystem services, especially in tropical forests. Seed dispersal and predation, for example, are especially important ecological processes for shaping plant diversity and composition; however, they can be strongly affected by such changes. Understanding factors that limit seed removal and, consequently, the final seed fate in human-modified landscapes is vital to enhancing our knowledge of ecosystem functioning. By using structural equation models, we evaluated the direct and indirect effects of landscape structure, anthropogenic stressors, and the abundance of terrestrial mammals on seed removal patterns of <i>Eschweilera ovata</i> (Lecythidaceae), a common large-seeded species, in 18 Atlantic Forest fragments in southern Bahia, Brazil. We used camera traps to record potential seed-removing mammals and spool line experiments to assess the ultimate fate of the seeds. We reveal a direct effect of patch size on the percentage of seeds removed, with seed removal decreasing in larger forest fragments. Our results also demonstrated a negative effect of human population density on mammal abundance; although a direct effect of mammals on seed removal was not detected. We, therefore, recommend that anthropogenic pressures should be mitigated to enhance the recovery of mammals in fragmented forest landscapes and that further research incorporate other potential predictors to better elucidate the complex patterns of seed removal in tropical forests.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143689487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inga and Lianas Are Key Players in the Tropical Nitrogen Cycle of Brazilian Atlantic Forest: Insights From Linking Rates of Nitrogen Fixation With DNA Barcoding Root Identification","authors":"J. B. Winbourne,&nbsp;K. E. Hasenstab-Lehman,&nbsp;A. N. Egan,&nbsp;D. Piotto,&nbsp;W. J. Kress,&nbsp;S. Porder","doi":"10.1111/btp.70021","DOIUrl":"https://doi.org/10.1111/btp.70021","url":null,"abstract":"<div>\u0000 \u0000 <p>Legumes are abundant and diverse in neotropical forests, and many have the potential to fix atmospheric di-nitrogen, playing a unique role in tropical forest nutrient cycling. Despite their recognized importance, it remains difficult to link rates of nitrogen fixation occurring in root nodules belowground to the responsible host plant. To overcome this challenge, we use DNA barcodes of root nodules, upon which rates of nitrogen fixation have been quantified, to determine which legumes are fixing nitrogen, and how much, during forest succession in the Atlantic Forest of Bahia, Brazil. We developed a three-locus DNA barcode (<i>rbcL, trnH-psbA,</i> and <i>matK</i>) library for the legume tree canopy species. We then excavated root nodules, measured rates of nitrogen fixation, and compared DNA barcode sequences of root nodules to this library and published sequences using a community-curated <i>matK</i> phylogenetic framework. We identified a diversity of legume taxa actively fixing nitrogen. The majority of fixation (&gt; 50%) however, was found to be due to the genus <i>Inga</i> in secondary forest stands, and in mature forests, two genera of lianas (woody vines) (<i>Macropsycanthus</i> &amp; <i>Dioclea</i>) represented 70% of the observed nitrogen fixation. <i>Inga</i> had the greatest range of nitrogenase efficiency (nitrogen fixation per unit of nodule biomass). This study illustrates the key role of <i>Inga</i> in the recovery of the nitrogen cycle in secondary regrowth in this region, the sustained inputs of nitrogen in mature forests by lianas, and the utility and challenges of DNA barcoding for linking rates of nitrogen fixation to the responsible host plant.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143689322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Large Trees Are Most Influential for Long-Term Persistence of Caribbean Pine (Pinus caribaea var. hondurensis) Populations in Lowland Belize Savannas","authors":"Jennifer M. Fill,&nbsp;Mario Muschamp,&nbsp;Fanny Tricone,&nbsp;Raelene M. Crandall,&nbsp;Rick Anderson","doi":"10.1111/btp.70019","DOIUrl":"https://doi.org/10.1111/btp.70019","url":null,"abstract":"<div>\u0000 \u0000 <p>Caribbean pine (<i>Pinus caribaea</i> var. <i>hondurensis</i>) is the dominant canopy tree in lowland savannas of Central America and naturally experiences frequent fire. Previous research showed differential survival of juvenile pines between open, grass-dominated environments and shrub-dominated savanna environments. To date, however, no studies have modeled the population dynamics of natural stands. We studied Caribbean pine population dynamics in coastal Belize to establish a baseline and determine the relative importance of size-based stages and vital rates to population growth. We collected field data on pines from 2017 to 2021 in open and shrubby environments and grouped individuals into three size-based stage classes. We calculated transition probabilities among stages for two 2-year time intervals (2017–2019, 2019–2021) based on growth and survival and on reproduction, adding them to yield a single matrix for each environment and time interval. These transition matrices were then averaged for each environment, and mean matrices were used to calculate the population growth rates (lambda). We compared these population growth rates with those estimated from simulations using mixed modeling of vital rates, where the time interval was modeled as a random effect. We explored elasticity values for each transition in the mean matrices. Lambda was lower in open than in shrubby savanna environments in both analyses. Population growth rates were most sensitive to the growth and survival of pole and large trees in both savanna environments. Although the elasticity of seedling and juvenile trees was relatively low, these stages are naturally important in both environments, especially after major disturbances such as hurricanes.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143639183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Low Requirement on the Nest Site Selection Influencing the Invasion Success of House Geckos","authors":"Romana Aguiar Andrade,&nbsp;Daniel Cunha Passos","doi":"10.1111/btp.70018","DOIUrl":"https://doi.org/10.1111/btp.70018","url":null,"abstract":"<div>\u0000 \u0000 <p>The selection of nesting sites is fundamental for the reproductive success of oviparous species. However, there are gaps regarding how animals select their reproductive sites, especially among species that do not build their nests; that is, they use natural cavities for oviposition, as is the case with many lizards. Herein, we evaluated how the physical structure and microclimatic conditions of tree hollows influence the selection of oviposition sites in a widely distributed exotic lizard, <i>Hemidactylus mabouia</i> (Squamata, Gekkonidae). We hypothesized that the choice of oviposition sites by females would consider: (a) structural properties of the sites related to the vulnerability of eggs to predation; and/or (b) microclimatic conditions of the sites associated with the stability of the egg incubation process. Over the course of a year, we monitored the use of 53 tree cavities on a weekly basis, recording a total of 69 <i>H. mabouia</i> nests. The width of the opening of the sites, their height in relation to the ground level, and the temperature variation in the hollows did not influence the choice of oviposition sites. However, cavities with less variation in humidity were used more frequently. Our findings contribute to the understanding of selection criteria for oviposition sites in species that use tree cavities as nests in general. Furthermore, we discuss the implications of the generalist habits of <i>H. mabouia</i> in the context of biological invasion, suggesting that the low requirements for the selection of reproductive sites may constitute a determining factor for the successful invasion of exotic lizards.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial: Biotropica Announces a New Paper Category: Synthesis","authors":"Jennifer S. Powers,&nbsp;Francis Q. Brearley,&nbsp;Jayashree Ratnam,&nbsp;Eleanor M. Slade","doi":"10.1111/btp.70020","DOIUrl":"https://doi.org/10.1111/btp.70020","url":null,"abstract":"&lt;p&gt;What does it take to tackle big questions in ecology, evolution, and conservation that do not have quick answers? Several important tools have emerged in recent years including literature synthesis and meta-analysis (Halpern et al. &lt;span&gt;2023&lt;/span&gt;; Lortie &lt;span&gt;2014&lt;/span&gt;), complemented by distributed network experiments (Powers et al. &lt;span&gt;2009&lt;/span&gt;; Roslin et al. &lt;span&gt;2017&lt;/span&gt;). Synthesis often consists of meta-analyses and data integration, wherein researchers compile and analyze data from multiple sources in the literature. Often, these studies integrate information from multiple spatial sources and yield inferences at continental or global scales. The success of this approach is underscored by the creation of centers for ecological synthesis, such as the National Center for Ecological Analysis and Synthesis (NCEAS) in the United States or the Synthesis Centre for Biodiversity Sciences in Germany (sDiv). In parallel, other research groups have developed distributed ecological networks of experiments and/or observations, for example, NutNet or DarkDivNet (Borer et al. &lt;span&gt;2014&lt;/span&gt;; Pärtel et al. &lt;span&gt;2025&lt;/span&gt;). In these projects, researchers focus on different locations, but they all implement standardized methods to yield geographically comparative data. These approaches have undoubtedly contributed to our understanding of ecological patterns and processes at broad spatial scales, and yet they are not the only method of synthesis. The nature of tropical ecological research often means that some researchers and research groups return to the same study location year after year, building programs of investigation over decades that may integrate the role of fluctuating environmental conditions in their study system. This approach chips away at big questions one paper at a time and yields major results when synthesized (e.g., Melin et al. &lt;span&gt;2020&lt;/span&gt;).&lt;/p&gt;&lt;p&gt;Meta-analyses or literature reviews typically begin with database searches, such as Google Scholar or Web of Science, and discourage “excessive” self-citation, as the objective is to derive generalizable patterns across many published studies. While global syntheses have provided broad ecological insights, this may have cost us the types of ecological insights that come from “slow ecology” focused on a deeper understanding of a single study system at one location (Billick and Price &lt;span&gt;2010&lt;/span&gt;). Such studies, with the deep glimpses they provide into the natural history of an ecosystem, are often the source of novel observations and mechanistic understanding in ecology. They are also critical for conservation and management that require local action. We contend that we lack a platform that encourages groups of investigators to synthesize and integrate their findings from a concerted and coordinated program of study conducted in a single place over decades, that is, papers where the goal is to trace the arc of a research program over many years through “self-cit","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/btp.70020","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143629868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Population Variability and Apparent Recent Decline of River Birds in the Indian Himalaya","authors":"Ankita Sinha,&nbsp;Nilanjan Chatterjee,&nbsp;Steve J. Ormerod,&nbsp;Ramesh Krishnamurthy","doi":"10.1111/btp.70017","DOIUrl":"https://doi.org/10.1111/btp.70017","url":null,"abstract":"<p>Abundance estimates are critical to animal conservation in the tropics and sub-tropics, but assessments for some species and ecosystems in these regions are poorly developed. Estimates are particularly scarce for subtropical mountain rivers where some river organisms reach their greatest global diversity while being at risk from global change. We addressed these issues along rivers in the western Indian Himalaya, focusing on 12 bird species with varying dependence on river production, distribution, abundance, and detectability. We estimated river bird abundance through repeat field counts across 5 years using N-mixture models to correct for imperfect detection from sparse data over an altitudinal range of 330–3100 m. Estimated abundances were modeled against elevation, flow, and river width as covariates. Detection probabilities overall were greatest in flycatching insectivores connected closely to the river channel and lowest in two piscivorous kingfishers. Patterns of abundance also varied among groups particularly in relation to elevation, with river passerines mostly recorded at mid and higher elevations and piscivorous taxa recorded mostly below 1600 m a.s.l. Five species apparently declined in overall population size by 5%–10% across the 5-year study, in three cases matching national scale trends recorded by citizen science platforms. Our results reveal the utility of open <i>N</i>-mixture models in assessing population trends of specialized river organisms in subtropical mountain environments where high-resolution data are difficult to collect. The data also hint at possible threats to Himalayan rivers that could affect this globally unique community of river birds.</p>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/btp.70017","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143530440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}