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升金湖是长江中下游地区典型的浅水通江湖泊,是东亚-澳大利西亚候鸟迁徙路线上水鸟重要的越冬地. 2017年11月-2018年3月,以该湖泊越冬鸭属(Anas)鸟类为研究对象,对其在芦苇湿地、芡实塘、退耕还湿和水生植被恢复湿地4种湿地生境中的群落结构、行为特征及其环境影响因素进行了研究. 结果表明,升金湖分布有10种越冬鸭属鸟类,斑嘴鸭(Anas poecilorhyncha)、绿翅鸭(A. crecca)和绿头鸭(A. platyrhynchos)为该属鸟类群落的优势种. 鸭属鸟类群落在越冬前期种类和数量最多,在整个越冬期,鸭属鸟类在芦苇湿地中种数、数量、密度和多样性指数最高. 在水生植物盖度高、人为活动弱的芦苇湿地,鸭类的主要行为是休息;在食物资源丰富、人为活动强的芡实塘和退耕还湿湿地,其主要行为是觅食和警戒. 鸭属鸟类群落种数、数量、密度和多样性指数与湿地的面积、水域面积、水生植物盖度呈正相关,与干扰度和水深呈负相关. 觅食时间与气温和沉水植物的盖度呈正相关,与水深和干扰度呈负相关,警戒时间与干扰度呈正相关,与挺水植物的盖度呈负相关. 各种恢复类型的湿地生境成为越冬鸭属鸟类的重要栖息地,因此恢复多种湿地栖息地对于越冬水鸟的保护具有重要意义. 相似文献
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We describe a large collection of fossil ‘waterfowl’ bones that are referable to the extinct clade Presbyornithidae (Anseriformes). All of these fossils were collected between 1971 and 1994 from Upper Paleocene and Lower Eocene sediments at the Tsagaan Khushuu site in the Gobi Desert of southern Mongolia. The collection includes specimens referred to a new small species within the genus Presbyornis Wetmore, 1926 as well as large numbers of bones that we place in the genus Presbyornis. On this basis of the Tsagaan Khushuu collection we suggest that several species of Presbyornis likely coexisted in this region; indeed, the presence of large numbers of middle‐sized, morphologically consistent but probably ecologically disparate species at the Tsagaan Khushuu site is consistent with the range of variation seen, for example, in taxa of extant dabbling ducks (Anatini). Although the anatomy and phylogenetic position of Presbyornithidae (in particular Presbyornis) are well known, this material from Mongolia further demonstrates the prevalence of these birds in aquatic and semi‐aquatic habitats by the earliest Paleogene. Because presbyornithids are also well documented from the late Cretaceous, their palaeoecology and morphological diversity provides a clue to selective avian survivorship across the Cretaceous‐Paleogene (K‐Pg) boundary. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Joanna Burger J. Richard Trout Wade Wander Glenn S. Ritter 《Estuarine, Coastal and Shelf Science》1984,19(6):673-689
The abundance and distribution of ducks (Anatini, Cairinini, Aythyini, Mergini, Oxyurini) were examined at Jamaica Bay Wildlife Refuge, a coastal estuary on Long Island, New York. The refuge contains a variety of tidal habitats as well two freshwater impoundments. The largest concentrations of diving ducks were present in March and April, and from October through December; while the largest concentrations of dabbling ducks were present from June through December. Thus, diving ducks used the refuge on migration whereas dabbling ducks used the refuge during and following the breeding season. Time of year was thus the most significant factor affecting distribution and abundance. Some species were present all year, including Black Duck Anas rubripes, Mallard A. platyrhynchos, Gadwall A. strepera, and Ruddy Duck Oxyura jamaicensis. Although both dabblers and divers used all areas of the bay, dabblers used both ponds while divers used only the East Pond. Dabbling ducks concentrated in the bay at low tide, and on the ponds at high tide. There were more divers on the bay on a falling tide although tide direction did not influence the abundance or distribution of dabblers. Temperature and wind variables influenced the distribution of all ducks: they used the bay at low temperatures, and rafted in large flocks on the bay in intermediate, Northwest winds. Only the numbers and distribution of dabblers were significantly influenced by cloud cover. We conclude that abiotic factors influence the abundance and distribution of ducks on Jamaica Bay Wildlife Refuge, and that tidal factors should be considered when managing migratory or wintering populations of ducks. 相似文献
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