lake sturgeon

lake sturgeon (Acipenser fulvescens) [state endangered]
Photo © Konrad P. Schmidt, University of Minnesota

The lake sturgeon has a cone-shaped snout with the mouth underneath and set far back. Four large barbels are present in front of the mouth. A small opening (spiracle) is located behind the eye. The upper lobe of the tail fin is longer than the lower lobe. The slate-colored, light-brown or yellow-green body is covered with bony plates. The belly is white. The lake sturgeon may reach eight feet in length and over 300 pounds in weight, but growth is very slow.

The lake sturgeon lives in lakes and rivers in areas with firm, silt-free bottoms of gravel, rock and sand. Maturity is reached at about age 20 years. Lake sturgeons commonly live 40 years and have been known to live more than 150 years. This fish spawns in late spring, swimming up small streams to do so. Over 500,000 eggs may be deposited by the female on shallow, gravel riffles or rocky shoals. The female does not reproduce every year. The lake sturgeon feeds on the bottom using its extendible mouth to suck up small invertebrates like snails, insect larvae and crayfish.

​Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Acipenseriformes
Family: Acipenseridae

The lake sturgeon is endangered in Illinois mainly due to the inability of the fish to reach upstream spawning areas because of the construction of dams and the destruction of spawning areas through channelization, siltation, impoundment and pollution. Excessive fishing in the late 1800s and early 1900s contributed to the problem, too.