Pallid sturgeon are similar to shovelnose sturgeon, but with a longer and more pointed snout. The bases of the inner barbels are weakly fringed, and the base of an inner barbel is less than half the width of the base of an outer barbel. The bases of barbels form a crescent. The belly has only scattered embedded plates or is bare. The overall color is grayish white. It may exceed 30 inches and 10 pounds.
Endangered. If caught, return unharmed to water immediately.
Total length: 30–72 inches; weight: up to 100 pounds.
Rarely found but widely distributed. Confined principally to the Missouri and lower Mississippi rivers.
Habitat and Conservation
Pallid sturgeon are bottom dwellers in the Missouri and Mississippi rivers in Missouri. They live in areas of strong current that have firm sand substrates in the main river channels, such as along sand bars and behind wing dikes with deeply scoured trenches. Compared to the shovelnose sturgeon, the pallid sturgeon is restricted to areas of strong current.
Once a commercially fished species, overharvest, dam construction, and habitat loss have reduced their numbers to dangerously low levels. Another threat to their survival is hybridization with the more common shovelnose sturgeon.
Small fishes and immature aquatic insects that are sucked from the bottom sediments.
This species has been listed as Endangered by both the state of Missouri and the U.S. government. Thus it is not a game species and if caught must be released unharmed.
Restoration efforts include captive breeding and restocking of juveniles. Other efforts include habitat preservation: not altering channel island tips; avoiding channel alterations that limit or eliminate shallow, sloping bank habitat; and prohibiting new dams and impoundments, which further reduce habitat. Additionally, stream work should be avoided that disturbs the substrate in areas where juvenile or larval fish are found, from April through mid-June.
Known to live at least 40 years. Males mature at around 7 years of age, while females may not spawn until 15–20 years old.
Human-caused changes in our big rivers have brought the pallid sturgeon and shovelnose sturgeon in more direct contact than they were historically, and the two species now compete directly and also breed and hybridize with each other. Hybridization could result in genetic swamping and eventually threaten the survival of the much less numerous pallid sturgeon species.
The pallid sturgeon is beautifully adapted for its big-river environment. Its streamlined shape enables it to withstand and navigate the strongest river currents; like a catfish, it relies more on scent than on sight to sense its environment. The whitish color is a response to the murky, turbid, low-light conditions, similar to the unpigmented condition of cave fish.