The shortnose sturgeon is a bony, ancient-looking fish that lives mostly in the Potomac and Susquehanna rivers. It is an endangered species.
The shortnose sturgeon has a brown, tan or bluish-black body and a whitish belly. It has no scales, but five rows of bony plates, called scutes, cover its head and body: one along the back, one along either side and two along the belly. It grows very slowly, eventually reaching about 4.5 feet in length and weighing 50 pounds. It has a short, broad snout with a rounded tip, with four sensory barbels on the underside of its snout. Its mouth is soft and toothless.
Shortnose sturgeon live at the bottom of low-salinity rivers, moving to deeper waters in winter.
This fish spends most of the year in the lower reaches of its spawning river, occasionally venturing out into the Chesapeake Bay. To spawn, it will move upriver to cool, fast-moving waters. Small spawning populations have been recorded in the Potomac and Susquehanna rivers. The shortnose sturgeon is extremely rare.
Shortnose sturgeon prey upon benthic creatures including clams and other mollusks, crustaceans, worms and insects. As bottom-feeders, they use their snout to root through the mud and find their prey, then suck it into their mouth like a vacuum.
Because of the bony plates covering its body, the shortnose sturgeon has few natural predators. Human activities such as pollution, historic overfishing and damming of rivers threaten sturgeons.
Sturgeons are anadromous, meaning they live in the ocean and spawn in freshwater rivers. Spawning occurs from February to April in the fast-flowing freshwater river the fish was born in. Females lay anywhere from 27,000 to 208,000 eggs over an area with a rocky bottom. Once hatched, the tadpole-like larvae remain in sheltered areas for about two weeks before being slowly carried downstream to merge with adults. By the time they are just an inch long, juveniles begin to resemble and act like adults. Males do not reach sexual maturity until they are 3 to 5 years old. Females take 6 to 7 years to mature. Males can live to 30 years, while females can live more than 60 years.