Bird nest July to September), it is not in others, and the swiftlets are declining in areas where the harvest reaches unsustainable levels. Some species of birds are also considered nuisances when they nest in the proximity of human habitations. Feral pigeons are often unwelcome and sometimes also considered as a health risk. The Beijing National Stadium, principal venue of the 2008 Summer Olympics, has been nicknamed "The Bird Nest" because of its architectural design, which its designers likened to a bird's woven nest. In the Victorian era, naturalists often collected bird's eggs and their nests. The study of bird nests is
Charentsavan City Stadium turn the venue into an all-seater stadium by the end of 2017. The stadium is currently used by several youth football schools of Kotayk Province. Charentsavan City Stadium Charentsavan City Stadium (), is a multipurpose stadium in Charentsavan, Armenia, mainly used for football games, as well as local events of athletics. It was opened in 1970 and has a capacity of 5,000 spectators. It served as a home ground to FC Moush Charentsavan between 1990 and 1994, when the club was dissolved and retired from professional football. On the occasion of the "2017 Charentsavan youth capital of Armenia", the stadium's