Migratory Waterbird Species Research Articles

Identifying ecological and life-history drivers of population dynamics of wetland birds in South Africa

Identifying species most vulnerable to environmental change requires reliable estimates of population trends and identification of traits that tend to be associated with these trends. Using state-space models that explicitly describe how the population size changes over time, we estimated population trends of 25 non-migratory African, 13 intra-African migrants, and 16 Palaearctic migratory waterbird species during 1995–2009 in South Africa. Using the average of the slope of the last five years (2005–2009), we used phylogenetic generalized least squares analyses to identify relationships with life-history (parental care, extent of polygamy, chick development, body size, average brood size) and ecological traits (migratory status, breeding latitude, foraging guild, wintering habitat type). The significant predictors of population trend were migratory status, average brood size, type of chick development (altricial, semiprecocial, precocial), and extent of male polygamy (0%, = <20%, >20%). Long-distance Palaearctic migrants and African non-migratory species on average suffered the greatest magnitude of decline, intra-African migrants showed population increase. There was a negative relationship between population trend and average brood size with an increase in brood size resulting in negative trends. Altricial species and species with some extent of polygamy (=<20%) had the greatest population increase. Our results provide evidence that these recent population trends were non-random with respect to life-history traits.

不同尺度下停歇点湿地对迁徙水鸟的影响研究综述

PDF HTML阅读 XML下载 导出引用 引用提醒 不同尺度下停歇点湿地对迁徙水鸟的影响研究综述 DOI: 10.5846/stxb201510262158 作者: 作者单位: 中国科学院生态环境研究中心,中国科学院生态环境研究中心,中国科学院生态环境研究中心,中国科学院生态环境研究中心 作者简介: 通讯作者: 中图分类号: 基金项目: 国家"十二五"科技支撑计划项目课题（2012BAC07B04） The effect of stopover wetlands on migratory waterbirds at different scales: a review Author: Affiliation: State Key Laboratory of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,State Key Laboratory of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,State Key Laboratory of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,State Key Laboratory of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:停歇点湿地是迁徙水鸟重要的能量补给地，在水鸟每年的往返迁徙过程中具有十分重要的生态意义。近年来随着全球变化和人类活动增加，迁飞路线上的停歇点湿地正发生剧烈变化。各个停歇点湿地的生境变化及周围环境不仅是影响水鸟栖息地适宜性的重要因素，还改变了各路线上迁徙水鸟的种群大小和群落多样性。分析不同尺度下停歇点湿地影响迁徙水鸟种群变化的主要生态因子和环境因素，不仅有助于理解各停歇点景观变化的生态效应，也可为迁徙水鸟种群保护提供理论支持。首先分析了在栖息地斑块尺度上停歇点湿地内的水、食物、栖息地格局和人类干扰等生态要素对水鸟觅食和栖息活动的影响；其次，分析了景观尺度上湿地周围的气候变化、土地利用和外来生物等环境条件在各停歇点对水鸟栖息地质量的改变；最后，基于多尺度条件下湿地影响因素的耦合效应，分析了当前湿地生境与水鸟种群关系研究中存在的主要问题，并总结了对湿地和水鸟保护的启示。 Abstract:Stopover wetlands are important refueling stations for numerous migratory waterbird species, and are ecologically significant in the annual cycle of birds. Recently, stopover wetlands located on flyways were faced with dramatic changes owing to global warming and increasing human activities. Previous studies have suggested that both habitat and environmental factors of these wetlands contributed to the habitat suitability of various species, and the key factors affecting the abundance and diversity of waterbird communities. Therefore, it would be helpful to understand the ecological effects of landscape changes at each stopover by analyzing the diverse habitats and environmental factors that affect various waterbird populations during migration. Furthermore, it would provide theoretical support necessary to formulate effective conservation strategies. In this review, we systematically analyzed how habitat factors such as water body, food resources, habitat configuration, and human disturbance affect the foraging and resting of waterbirds at a local scale. Then, we discussed various environmental contexts, including global warming, land use, and exotic species, that indirectly affect habitat suitability and bird migration at the landscape scale. Finally, on the basis of the coupling effects of various influencing factors that were related to stopover wetlands at different scales, we summarized some shortages based on the research of the present relationships between wetlands and waterbirds, and suggested some priorities for future studies and environmental conservation. 参考文献 相似文献 引证文献

Abundance models improve spatial and temporal prioritization of conservation resources.

Conservation prioritization requires knowledge about organism distribution and density. This information is often inferred from models that estimate the probability of species occurrence rather than from models that estimate species abundance, because abundance data are harder to obtain and model. However, occurrence and abundance may not display similar patterns and therefore development of robust, scalable, abundance models is critical to ensuring that scarce conservation resources are applied where they can have the greatest benefits. Motivated by a dynamic land conservation program, we develop and assess a general method for modeling relative abundance using citizen science monitoring data. Weekly estimates of relative abundance and occurrence were compared for prioritizing times and locations of conservation actions for migratory waterbird species in California, USA. We found that abundance estimates consistently provided better rankings of observed counts than occurrence estimates. Additionally, the relationship between abundance and occurrence was nonlinear and varied by species and season. Across species, locations prioritized by occurrence models had only 10-58% overlap with locations prioritized by abundance models, highlighting that occurrence models will not typically identify the locations of highest abundance that are vital for conservation of populations.

Climate‐driven changes in winter abundance of a migratory waterbird in relation to EU protected areas

AbstractAimSpecies are responding to climate change by changing their distributions, creating debate about the effectiveness of existing networks of protected areas. As a contribution to this debate, we assess whether regional winter abundances and distribution of the SmewMergellus albellus, a migratory waterbird species listed on Annex I (EUBirds Directive) that overwinters exclusively in European wetlands, changed during 1990–2011, the role of global warming in driving distributional changes and the effectiveness of the network of Special Protection Areas (SPAs,EUBirds Directive) in the context of climate change.LocationEurope.MethodsWe used site‐specific counts (6,883 sites) from 16 countries covering the entire flyway to estimate annual abundance indices and trends at country, region (north‐eastern, central and south‐western) and flyway scales, inside and outsideSPAs. We fitted autoregressive models to assess the effect of winter temperature on the annual abundance indices whilst accounting for autocorrelation.ResultsThe Smew wintering distribution shifted north‐eastwards in Europe in accordance with the predictions of global warming, with increasing numbers in the north‐eastern region and declines in the central region. Trends in wintering numbers were more positive inSPAs on the north‐eastern and south‐western part of the flyway. However, a large proportion of the wintering population remains unprotected in north‐eastern areas outside of the existingSPAnetwork.Main conclusionsSPAs accommodated climate‐driven abundance changes in the north‐eastern region of the wintering distribution by supporting increasing numbers of Smew in traditional and newly colonized areas. However, we highlight gaps in the current network, suggesting that urgent policy responses are needed. Given rapid changes in species distributions, we urge regular national and international assessments of the adequacy of theEUNatura 2000 network to ensure coherence in site‐safeguard networks for this and other species.

Selection of ecological indicators for the conservation, management and monitoring of Mediterranean coastal salinas

Salinas systems are artificial wetlands which are interesting from the viewpoint of nature conservation. They play an important role both as habitats for migratory waterbird species and as nodes of biotic connectivity networks. In the Mediterranean basin, where the coastal salinas are highly significant as alternative and complementary habitats for waterbirds, a process of abandonment occurs, and many seminatural systems of this kind are disappearing. This abandonment is having serious consequences for migratory bird populations and for the ecological role these play. In the present paper, this group of waterbird species has been used to evaluate these wetlands for conservation purposes. We have developed a methodological approach for the selection of ecological indicators for the conservation and management of these Mediterranean habitats and waterbird assemblages, the main consumers therein. The stepwise procedure developed constitutes a practical tool for this task. Application thereof enabled us to differentiate the habitats available for the waterbirds and to identify the biotic and abiotic indicators for the maintenance and management of the salina ecosystems. These variables can then be incorporated into monitoring programs.

The African-Eurasian Waterbird Agreement

Sylla, I.S., Boere, G.B. & Lenten, B. 2000. The African-Eurasian Waterbird Agreement. Ostrich 71 (1 & 2): 341. After nearly ten years of drafting and negotiation, the African-Eurasian Waterbird Agreement (AEWA) is now open for signature at the Ministry of Foreign Affairs of the Netherlands from 15 August onwards. This agreement aims to create a legal basis for concerted conservation and management policy by the Range States for migratory waterbird species. The AEWA is the first regional Agreement of vast areas of 80 million square kilometres covering the entire continents of Africa and Europe, as well as parts of Asia and a few Arctic islands of north-eastem Canada. It covers about 170 species of waterfowl. The Agreement has two parts that are both legally binding: Firstly the Agreement text, describing the philosophy, legal framework and provisions. The described General Conservation Measures in this part are based on two hdamental principles: (a) Parties shall take coordinated measures to maintain migratory waterbirds species in a favourable conservation status or to restore them to such a status; (b) In implementing the measures of paragraph 1, Parties should take into account the precautionary principle. The second part, an Action Plan, describing the conservation actions that Parties shall undertake in relation to priority species and issues, under the following headings, consistent with the general conservation measures: a) species Conservation; b) habitat conservation; c) management of human activities; d) research and monitoring; e) education and information; and f) implementation. These actions are based on the above mentioned Fundamental Principles. The Action Plan now is restricted to geese, swans ducks, ibises and storks.