Fish and Aquatic Conservation



illustration of a Pallid sturgeon

Pallid sturgeon

Scaphirhynhcus albus (Forbes & Richardson, 1905)

Cool Facts

Proof of the pallid sturgeons’ preference for turbid water is exhibited by their tiny eyes. Pallid find their food in the murky depths of river bottoms by utilizing their barbels, which are “whisker-like” and covered with sensitive chemoreceptors, that are similar to taste buds, to help them detect their food along the river bottom. Upon reaching maturity, pallid sturgeon become top level predators, feeding primarily on other fish. Pallid sturgeon are a long lived species and can live to be 60 years old. Pallid sturgeon are built to thrive in swift flowing water. Their anatomical structure which includes a flat bottom, humped back and hydrodynamic fin position allows them to hold their ground with very little effort. They are also one of the few fish that can also use their fins to pull themselves along the bottom in a crawling motion.

SIZE: Pallid sturgeon can grow to more than 6ft. (1.8 m) long and weigh up to 80 lbs. (36.4 kg)

RANGE: Palllid sturgeon primarily reside in the main channels of the Missouri River and Lower Mississippi River from Montana to Louisiana.

HABITAT: Adult pallid sturgeon inhabit large, deep turbid river channels, usually in strong current over firm sand or gravel.

DIET: Pallid sturgeon feed on immature aquatic insect larvae and small fish.

Natural History

Pallid sturgeon inhabit the main channels of large rivers. They prefer deep, turbid river channels with strong demersal currents. These fish are built to thrive in swift flowing water. Pallid Sturgeon often make long upstream journeys looking for the perfect place to spawn and swim back downstream when they are finished.

Pallid sturgeon do not reach maturity at an early age. Normally, male sturgeon do not mature until the age of 7 and female sturgeon do not mature until the age of 10. Upon reaching maturity pallid sturgeon will usually spawn every two to three years.

After hatching, tiny pallid sturgeon larvae will drift in the river current for ten days or more before settling down to the river bottom to feed and grow. They are very vulnerable during this juvenile life history stage.

Conservation

Just like other species of sturgeon, their populations were significantly overharvested by the commercial fishery in the 1900’s for their eggs or caviar. The pallid sturgeon was listed as Endangered under the Endangered Species Act in 1990 because of habitat degradation, declines in water quality throughout their range and the building of dams that impaired the pallid sturgeon’s ability to migrate to their natural spawning grounds.

The National Fish Hatchery System(NFHS) of the U.S. Fish and Wildlife Service stocks pallid sturgeon in U.S. rivers to help restore this very ancient and long lived species of fish. The Pallid sturgeon has changed little over the past 70 million years.