During August 2001, a syndrome characterized by acute lethargy and dyspnea was observed in a population of 45 lorikeets and lories in an open-air zoologic exhibit. The first death occurred on August 10, and within the next 12 days, nine more birds died (22% mortality rate). Hepatomegaly, reddening and congestion of the lungs, and injection of the serosal surface of the intestines were the common gross findings. Histologic changes, including fibrinonecrotic hepatitis and splenitis, bacterial emboli (liver, spleen, lung, kidney, proventriculus), pulmonary congestion and hemorrhage, and enteritis, were indicative of an acute, overwhelming bacterial septicemia. Salmonella typhimurium, with the same antibiogram, was isolated from four birds. Several birds had attacked and killed a snake on July 24, and Salmonella serogroup B (untypeable) was isolated from intestine and kidney samples of a garter snake caught in the open-air exhibit on August 28. Salmonella was also isolated from environmental samples of the exhibit but not from food preparation areas. After antimicrobial therapy, Salmonella spp. was not isolated from the surviving birds. The source of Salmonella in this outbreak remains unknown, but infection either directly or indirectly from snakes in the exhibit is possible. Contact between captive psittacine populations and reptiles should be avoided to prevent the risk of salmonellosis.