A thousand years ago it would have been common to see (or catch) this striking species in the Thames or other UK waters, with healthy populations existing throughout Europe. Now sturgeon are one of the most critically endangered groups on the planet (IUCN) and they are practically non-existent in UK rivers where they were once widespread. Conservation efforts have helped some sturgeon species (also known for their desirable caviar!) and strategies are in place to help re-establish a breeding population in UK waters .