Sturgeon

Sturgeons have rows of bony plates covering the head and along the body. The upper lobe of its tail fin is longer than the lower. Some species are long-distance travellers, capable of making round-trip journeys of up to 3,500 kilometres a year. Sturgeons can grow to be very large, up to 4.2 metres. All sturgeon species have been extensively exploited by humans for their meat and roe. As a result, sturgeons are among the most threatened animals in the world.

Sturgeons have a toothless mouth on the underside of the snout, preceded by four sensitive whisker-like barbels. These bottom-dwellers have bad eyesight and depend on their tactile barbels to locate food. To increase the coverage area of their food search, sturgeons sometimes wag their head from side to side. Scientists believe that sturgeons may carry taste buds outside their mouths to assist them in detecting prey.

Once located, prey is sucked up with its mouth, like a vacuum cleaner. Usually, the prey is swallowed whole, straight into the fish’s stomach. Due to its size in comparison with that of its prey, sturgeons spend much time scouring the mud for their meals. Besides invertebrate prey, they may also feed on dead fish. They may also take live fish such as smelt, shad and sculpin in the middle of their spawning process. Some species of sturgeon thrive off clams and crayfish.