<P> The baiji population declined drastically in decades as China industrialized and made heavy use of the river for fishing , transportation , and hydroelectricity . It has been credibly claimed , after surveys in the Yangtze River during the 1980s , that baiji could be the first dolphin species in history that humans have driven to extinction . A Conservation Action Plan for Cetaceans of the Yangtze River was approved by the Chinese Government in 2001 . Efforts were made to conserve the species , but a late 2006 expedition failed to find any baiji in the river . Organizers declared the baiji functionally extinct . The baiji represents the first documented global extinction of a `` megafaunal '' vertebrate for over 50 years since the demise of the Japanese sea lion and the Caribbean monk seal in the 1950s . It also signified the disappearance of an entire mammal family of river dolphins ( Lipotidae ) . The baiji 's extinction would be the first recorded extinction of a well - studied cetacean species ( it is unclear if some previously extinct varieties were species or subspecies ) to be directly attributable to human influence . </P>
<P> The baiji population declined drastically in decades as China industrialized and made heavy use of the river for fishing , transportation , and hydroelectricity . It has been credibly claimed , after surveys in the Yangtze River during the 1980s , that baiji could be the first dolphin species in history that humans have driven to extinction . A Conservation Action Plan for Cetaceans of the Yangtze River was approved by the Chinese Government in 2001 . Efforts were made to conserve the species , but a late 2006 expedition failed to find any baiji in the river . Organizers declared the baiji functionally extinct . The baiji represents the first documented global extinction of a `` megafaunal '' vertebrate for over 50 years since the demise of the Japanese sea lion and the Caribbean monk seal in the 1950s . It also signified the disappearance of an entire mammal family of river dolphins ( Lipotidae ) . The baiji 's extinction would be the first recorded extinction of a well - studied cetacean species ( it is unclear if some previously extinct varieties were species or subspecies ) to be directly attributable to human influence . </P>
when did the baiji river dolphin become extinct
when did the baiji river dolphin become extinct
late 2006
late 2006