Chinese sturgeons can grow to enormous proportions, with historical accounts of specimens topping 16 feet and an astounding 1,300 pounds. However, no sturgeons close to that size have been seen for decades, and the species is classified as critically endangered.

They’re seasoned travelers, making the longest migration of any sturgeon in the world. Every year, these prehistoric fish journey some 2,000 miles from the East China Sea to their spawning grounds in the Yangtze River.

Or, at least they used to. In recent years, this ancient migration cycle has been blocked by the Gezhouba Dam, built in the 1980s. Subsequent dams have placed new, possibly insurmountable, hurdles in the sturgeons’ upstream path and thrown the future of the