Cougar Mountain Zoo 2009, Peter Rittler continued in the zoo's management. The zoo collection features 32 exhibits of animal habitats concentrating on endangered species such as tigers, lemurs, wolves, reindeer, cranes, wallabies, macaws, and cougars, among others. On June 16, 2007, the zoo acquired two male Bengal tiger cubs, a royal white and a golden, who were born eight weeks apart in a Florida tiger preserve. The zoo added an additional two cubs in 2009. A glass-walled tunnel called the "Tiger Tunnel" enables visitors to view tigers in close proximity. In 2011, a 370-pound (168 km) tiger was photographed holding his paw up
Beijing Zoo collection. Leading Chinese universities also established a research presence in the zoo to study animal behavior and to breed endangered species. The zoo's development came to an abrupt halt during the Cultural Revolution as zoo staff were purged, research work stopped, and contacts with foreign zoos were severed. In the 1970s, as China forged diplomatic relations with the Western bloc, the zoo received animal gifts from the Australia, France, Mexico, Nepal, Spain, Sri Lanka, the United Kingdom, and the United States. The zoo also organized a four-year mission to Ethiopia, Kenya, and Tanzania, which brought back 157 species and 1,000