Millions of people around the world rely upon them for food - but fish are also pretty cool creatures. Literally.
The cold-blooded aquatic vertebrates often play a very important role in ecosystems - whether in rivers, lakes or oceans. Here's an automated compilation of content relating to fish.
Wild salmon, the so-called king of fish, is fighting for survival across much of the Northern Hemisphere. Many salmon populations are in steep decline in the face of dams, fish farming and climate change. And in Scotland, one project is focusing on forests to ensure survival of wild salmon at a crisis point. As it turns out, forests feed salmon just as salmon feed the forests.
Natural landscapes that have suffered from human intervention often need help coming back to life. That’s what the Dutch have discovered with the Markermeer — an enclosed portion of sea that was once a bay, and then, sealed off by a dam, was left to stagnate for half a century. That is, until they had the idea to build islands in the middle of it, inviting the reeds, birds and fish to return.