The Chinese River Dolphin, or Baiji (Lipotes vexillifer), found only in the Yangtze River, was declared "functionally extinct" after a 6-week expedition failed to find even one dolphin still living in the river. The Three Gorges Dam project, pollution and over hunting were cited as causes for extinction, giving the Baiji the unwelcome designation as the first large aquatic mammal driven to extinction by human activity since the 1950s.
Learn more about the Baiji's biology and conservation attempts in Conservation Biology, vol. 20, no. 3 June 2006, on the OhioLINK Electronic Journal Center.
image from the BBC.