After conducting an experiment on small freshwater fish calledkillifish, Japanese researchers suggest that germ cells, which are responsible for egg and sperm formation, could explain this phenomenon.

This uniquely American freshwater fish is found in the Mississippi River basin, the Great Lakes, and other small bodies of water east of the Great Lakes. It is a fierce fighter with sharp teeth ...

The Pecos pupfish could get federal protections as a threatened species, which would help protect the rare fish's habitat in southern New Mexico. The U.S. Fish and Wildlife Service is gathering public ...

Six critically endangered Mekong giant catfish — one of the largest and rarest freshwater fish in the world — were caught and ...

The shrinking size of Alaska salmon, a decades-long trend linked in part to warming conditions in the ocean, is hampering the ...

Climate change warms waters near the poles, enabling larger migratory fish like salmon to flourish. Equatorial populations ...

Millions of people rely on freshwater fish for food and as a source of income ... we need to consider both large and small waters, and to protect all our freshwaters: ponds, lakes, streams and ...

Freshwater fish populations that dwell nearer the poles are outperforming their equatorial counterparts, researchers have found.