The National Zoo has two campuses. The first is an 163-acre (66 ha) urban park located in Northwest Washington, D.C. that is 20 minutes from the National Mall by Metro. The other campus is the 3,200-acre (1,300 ha) Smithsonian Conservation Biology Institute (SCBI; formerly known as the Conservation and Research Center) in Front Royal, Virginia. On this land, there are 180 species of trees, 850 species of woody shrubs and herbaceous plants, 40 species of grasses, and 36 different species of bamboo. The SCBI is a non-public facility devoted to training wildlife professionals in conservation biology and to propagating rare species through natural means and assisted reproduction. The National Zoo is accredited by the Association of Zoos and Aquariums (AZA).
Altogether, the two facilities host about 1,800 animals of 300 different species. About one-fifth of them are endangered or threatened. Most species are on exhibit at the Zoo’s Rock Creek Park campus. The best known residents are the giant pandas, but the zoo is also home to birds, great apes, big cats, Asian elephants, insects, amphibians, reptiles, aquatic animals, small mammals and many more. The SCBI facility houses between 30 and 40 endangered species at any given time depending on research needs and recommendations from the zoo and the conservation community. The zoo was one of the first to establish a scientific research program. Because it is a part of the Smithsonian Institution, the National Zoo receives federal appropriations for operating expenses. A new master plan for the park was introduced in 2008 to upgrade the park’s exhibits and layout.
The National Zoo is open every day of the year except for December 25 (Christmas Day).