privately owned zoo opened in 1933 in Catskill, New York, U.S. It occupied more than 914 acres (370 hectares), of which 135 acres (55 hectares) were open to the public from May to October. The remainder of the zoo grounds were maintained as a breeding preserve. The Catskill Game Farm provided other zoos throughout the world with many varieties of captive-bred animals. The strength of its collection was what may have been the world's largest breeding stock of rare or threatened ungulates (ungulate), among which were scimitar-horned oryx, mountain zebra, onager, and dozens of other species. The zoo closed in 2006 due to financial difficulties.