Sofia Zoo marmoset, and macaques. The predator sector houses big cats, bears and small predators, including lions, tigers, leopards, pumas and brown bears. In January 2011 the zoo received eight Humboldt penguins on loan from Germany. The penguins are on loan for about 18 months, after which they will be returned, with any offspring to stay at the zoo. The zoo has some 1,400 individual birds representing 192 species. Waterbirds are housed in a lake, and Imperial eagles, Griffon vultures, Egyptian vultures and buzzards in a large walk-through aviary. Other species of birds at the zoo include ostriches, Silver pheasants, peacocks, flamingos,
Philadelphia Zoo (two ruffed lemurs, six ring-tailed lemurs, and two mongoose lemurs). All were members of endangered species. The animals died in their sleep from smoke inhalation (carbon monoxide poisoning); none were burned. Ten primates housed in an adjoining building, the Discovery House, survived. At the time of the fire, detection equipment existed in only 20 percent of the zoo buildings; the primates building, which had been constructed in 1985, was not one of them. In the ten months following the fire, the zoo installed fire detection equipment in all animal buildings. On July 1, 1999, the zoo opened a new primate