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A swimming fossil, the shortnose sturgeon is a primitive fish predating dinosaurs, characterized by rows of armor-like plates along its sides and a mostly cartilaginous body. Its name refers to its short shovel-shaped snout. Rarely exceeding 3-4 feet in length, the shortnose is a small sturgeon. Its body is usually olive-yellow to bluish gray with a white to yellow belly. Only occasionally entering the open sea, the shortnose lives in rivers, lakes, estuaries, and bays along the Atlantic coast from New Brunswick, Canada to Florida.
Shortnose sturgeon migrate upstream to spawn in freshwater areas, laying 40,000-200,000 eggs on rocky river bottoms or gravel. Eggs hatch after about 13 days, and the young slowly drift downstream, feeding as they go, eventually joining the adult population as juveniles. Bottom feeders, the sturgeon eats crayfish, shrimp, mussels, snails, insect larvae, sludge worms, and plants. Maturation depends on region. In the southern part of its range, males mature after 2-3 years, females after 4-6 years. Northern fish mature more slowly, taking as long as 10-15 years. They are relatively long-lived fish, females living as long as 67 years.
Though populations were once overexploited for eggs and smoked-flesh, shortnose caviar is now unlikely to grace affluent tables. It is Endangered in the United States, and the IUCN lists it as Vulnerable. The main threat to the species is loss and degradation of habitat. Damming of its native rivers prevents it from reaching spawning areas.
Nature picture credits (left to right): Photo © Christopher Holbrook (in hand); Photo © Christopher Holbrook (in tank).
