三十多种、上万只鸟儿齐聚于此，来密云观鸟

Core Viewpoint - The article highlights the increasing popularity of Miyun as a natural habitat for migratory birds, attracting numerous birdwatchers and photography enthusiasts due to its rich biodiversity and successful ecological conservation efforts [1][9]. Group 1: Birdwatching Experience - Over thirty species and thousands of birds have gathered in Miyun, creating a spectacular "bird sea" phenomenon that draws many visitors [1]. - Birdwatchers report seeing large numbers of swans and other birds, with one enthusiast noting the presence of fifty to sixty swans during a visit [5]. - Local residents express a sense of anticipation and joy as migratory birds return annually, likening it to meeting old friends [7]. Group 2: Ecological Significance - The attraction of birds to Miyun is attributed to the area's commitment to ecological preservation, aligning with the principle that "lucid waters and lush mountains are invaluable assets" [9]. - Miyun Reservoir maintains a stable water quality that meets the Class II surface water standard, contributing to a healthy ecosystem [9]. - The region supports a complete biological chain, providing an ideal habitat for migratory birds [10]. Group 3: Bird Species Diversity - A total of 419 wild bird species have been recorded in Miyun, including 22 species under national first-class protection and 73 species under second-class protection [12]. - The area is recognized for its diverse bird population, which includes 99 species protected at the municipal level [12]. Group 4: Birdwatching Locations - Recommended birdwatching spots include Yunmeng Bridge, Miyun Reservoir regulation pool, and Taishitun Xiaocao Village, creating a network of locations for observing birds [14]. - Specific locations are suggested for viewing different bird species, such as swans and cranes, with tips for minimizing disturbance to the birds [19][20].