The American paddlefish, polychaete, or paddlefish (Polyodon spathula) is a species of freshwater sturgeon in the paddlefish family. It is found in the Mississippi River basin and Lake Huron. 1)
The snout — a rostrum shaped like a horizontally arranged paddle — is sometimes half the length of its entire body and functions as a sensory organ. 2)
It characteristically grabs its food, which consists mainly of pelagic crustaceans, swimming with its mouth wide open in a zone devoid of vegetation, filtering out planktonic organisms with long and dense filtering appendages (juveniles initially have teeth that become resorbed over time), staggering in circles and often in eights. 3)
It spawns in early spring in rivers and lakes in turbid water with sandy gravel or rocky bottom. The female lays 80-250 thousand grains of eggs. She then forms large flocks that swim into larger tributaries or lakes. In its habitat, it stays away from the shore at considerable depths. 4)
Because paddlefish is considered to be an ancient species, it is illegal to harvest for caviar. Harvesting paddlefish is considered poaching. 5)