Most of These Giant Fish Were Alive During WWII

A large fish native to North America has caught the attention of scientists in recent years due to its impressive lifespan of a century or longer. But new research spells bad news for the bigmouth buffalo—according to the BBC, in areas examined by researcher Alec Lackmann of University of Minnesota, Duluth, it's been 60 years since a new generation of the fish lived to adulthood.

• Fascinating longevity: The bigmouth buffalo can reach up to 127 years (and likely even longer), making it the world's longest-living freshwater fish. And even more remarkable, they don't seem to decline biologically as they age. The fish can weigh more than 50 pounds.
• Missing young: The fish's longevity prompted more studies, which raised an alarming observation: despite regular and successful spawning, the vast majority of bigmouth buffalos are adults, with most of the population born before WWII. "This is something that's completely unparalleled in the animal kingdom as far as we know, for a species to be going so long without successfully having another generation," Lackmann told UMD News. Researchers believe the young get picked off by native predators, like pike fish. Habitat destruction via dams may also play a part.
• Uncertain future: Because bigmouth buffalos aren't commercially important, little effort has been dedicated to studying them until recently. Without environmental protections or a swath of data, some fear the window to study the species' longevity—and how to help keep their population from dwindling drastically once the oldest fish begin dying out—is shrinking.

(Another giant fish thought to be extinct has been rediscovered.)