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
The Burnside Nest the way birds create nests. Objects woven into the nest include a box-spring, part of a chair, rebar, a street sign, and two-by-fours. Wingate has said of the sculpture, "Only humans consider nature as separate from themselves. The bird does not. Therefore, it forages for materials that are usable for the nest and doesn't care if they're 'natural' or not, as long as they work." Despite having a land-use permit from the Portland Development Commission, Wingate was stopped four times by local police officers on the day he began creating the sculpture. It was unveiled on May 10, 2014. During