MINNESOTA – Recent findings show bigmouth buffalo fish have perplexingly long lives and appear to get healthier as they age. But scientists are worried their population is about to crash. If you ever find yourself on the shores of Minnesota’s Rice Lake in May time, you may be able to spot swarms of large fish bodies mingling among the wild rice plants in water barely a few feet deep.

These are bigmouth buffalo fish, and they are the world’s longest-lived freshwater fish. Some live for over 100 years.  Every year, these huge fish – which can weigh more than 50lb (23kg) – traverse through Rice River to spawn and reproduce in the lake. But the regularity of this spawning belies a hidden conservation concern: for more than six decades now, no new generations of young fish here have made it to adulthood.  Bigmouth buffalo have remained understudied for decades. In the last few years, however, scientists have begun to realise how unique these huge and incredibly long-lived fish truly are – even as they also uncover how imperilled they may be. (BBC)