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
Stadium Authority of the City of Pittsburgh Stadium Authority of the City of Pittsburgh The Stadium Authority of the City of Pittsburgh (also known as the Stadium Authority) is a municipal authority that was charged with the construction of Three Rivers Stadium and the management of the land on which it stood following its 2001 demolition. It currently owns the West General Robinson Street Garage and surface parking lots near PNC Park and Heinz Field. The Stadium Authority also leases parking facilities north of PNC Park. It was formed on March 9, 1964 by the City of Pittsburgh under its authority under the "Public Auditorium Authorities Law