摘要
This paper reviews the population trends and threats for the 15 species of cranes, and comments on conservation priorities for the family as a whole. Cranes occur on ifve continents, with greatest diversity in East Asia (nine species) and Sub-Saharan Africa (six species). Eleven crane species are threatened with extinction according to the IUCN Red List, including one species Critically En-dangered, three species Endangered, and seven species Vulnerable. Of the four species of Least Con-cern, population sizes for the Demoiselle (Anthropoides virgo) and Brolga (Grus rubicunda) are not well known but these species are declining in some areas. The Sandhill (G. canadensis) and Eurasian Cranes (G. grus) are the most abundant cranes and have rapidly increased in part due to their lfexible selection of foraging habitats and use of agriculture lands and waste grain as a food source. Status for six species-Grey Crowned (Balearica regulorum), Blue (Anthropoides paradise), Black-necked (G. nigricollis), Red-crowned (G. japonensis), Sandhill, and Siberian (G. leucogeranus)-are summarized in more detail to illustrate the diversity of population shifts and threats within the crane family. A crane threat matrix lists the major threats, rates each threat for each species, and scores each threat for the crane family as a whole. Four of the ifve greatest threats are to the ecosystems that cranes depend upon, while only one of the top threats (human disturbance) relates to human action directly impact-ing on cranes. Four major threats are discussed:dams and water diversions, agriculture development, crane trade, and climate change. Conservation efforts should be strongly science-based, reduce direct threats to the birds, safeguard or restore habitat, and strengthen awareness among decision makers and local communities for how to safeguard cranes and wetlands. Especially for the most severely threatened species, signiifcantly stronger efforts will be needed to incorporate our understanding of the needs of cranes and the ecosystems they inhabit into decisions about agriculture, water manage-ment, energy development and other human activities.
本文综述了全球范围内15种鹤类的种群动态趋势及受胁状况,并对鹤类的优先保护行动作了总体评价。全球五大洲均有鹤类生存,其中东亚种类最多(9种),其次是撒哈拉以南非洲地区(6种)。IUCN红色名录中11种鹤类为受胁而濒临灭绝物种,其中1种为极危物种(CR),3种为濒危物种(EN),7种为易危物种(VU)。在目前无危的4个鹤类中,蓑羽鹤(Anthropoides virgo)和澳洲鹤(Grus rubicunda)种群现状不是十分明确;但在某些地区,这两种的种群数量也在不断下降。沙丘鹤(Grus canadensis)和灰鹤(Grus grus)的数量最为丰富,种群数量也在快速增长,部分原因是它们能够灵活选择觅食地,并利用农田中废弃谷物作为食物来源。本文更为详细地总结了灰冠鹤(Balearica regulorum)、蓝蓑羽鹤(Anthropoides paradise)、黑颈鹤(G.nigricollis)、丹顶鹤(G.japonensis)、沙丘鹤及白鹤(G.leucogeranus)的现状,以说明鹤类家族内种群多样性的变化以及受胁情况。列出了鹤类面临的主要威胁,对各种鹤的威胁进行了逐一评价,并对鹤类家族所受的各种威胁计分。5种主要威胁中的4种均对鹤类赖以生存的生态系统产生直接影响,而另外一种则来自于人类活动的直接干扰。特别讨论了4种主要的威胁,即:水坝及河流改道、农业开发、鹤类贸易、气候变化。对鹤类的保护措施应切实具备科学依据,减少对鹤类的直接威胁,保护或修复栖息地环境,增强决策者及群众关于保护鹤类及湿地的意识。对受胁极其严重的鹤类,需要付出更多的努力来综合理解鹤类的需求及其所栖息的生态系统,并与农业、水资源管理及能源发展的决策结合起来。
