Contact Info
Missouri River Institute
The University of
South Dakota
414 E. Clark Street
Science Center
Vermillion, SD 57069

Financial support for website development provided by the
Living River Group
of the
Sierra Club




Channel Catfish (Ictalurus punctatus)

Channel catfish are very abundant in the Missouri River, and are highly prized by recreational anglers.  They can grow to weights of nearly 50 pounds, however most channel catfish on the Missouri River today are between 1-10 pounds.  They typically prefer well oxygenated moving water, and can be found in all sizes of lakes, rivers, and streams.  Channel catfish are omnivorous, and utilize a wide range of food items within their diet.  Primary diet items including small fish, crustaceans, snails and mussels, and secondary food items including aquatic insects, clams, and small mammals.  Channel catfish are easily identifiable, as they are usually bluish olive, gray or black on the upper part of the body, and becoming white below.  They typically have dark spots scattered along their sides, and older males are typically darker in color.  The head is proportionally wider than the rest of the body when seen from the top, with long barbells surrounding the mouth.  Another distinguishing feature of the channel catfish is the deeply forked tail.  On Tuesday, July 24, 1804 Clark wrote in his journals that "one of the men cought a white Catfish, the eyes Small & Tale reseumbing that of a Dolfin."  It is believed that was probably referring to the channel catfish and his observations provided the first written description of the new species to western science.   At the end of July, 1804, the journals noted that "Cat fish is very Common and easy taken in any part of this river."      

Paddlefish (Polyodon spathula)

The American paddlefish is one of the largest freshwater fish in North America, and is uniquely adapted to living in large rivers.  In the Missouri River, paddlefish commonly reach over 5 feet, and can weigh more than 60 pounds.  The largest paddlefish ever recorded was caught below Fort Randall dam in 1979 and weighed just over 120 pounds!  Paddlefish typically prefer slow moving waters of large rivers, and spend most of their time feeding within the water column.  Their diet is composed solely of tiny zooplankton, which is filtered out of the water by using filaments on their gill arches called gill rakers.  Paddlefish are easily identified by their unique "paddle" shaped snout (called a rostrum).  The rostrum is believed to serve two important functions.  First, it aids in stabilizing the large fish while swimming in the water column.  Secondly, it contains specialized receptors which can detect weak electrical fields within the water.  It is thought that these receptors aid the fish in detecting zooplankton.  Paddlefish populations are relatively stable within the Missouri River, and their harvest is closely regulated.  Despite their relatively healthy populations in the Missouri River, paddlefish still face several threats from sedimentation, river modification, poaching (for caviar), habitat loss, and an inability to migrate upstream due to dam construction.

Pallid Sturgeon (Scaphirhynchus albus)

Pallid sturgeon are listed by the U.S. Fish and Wildlife Service as a federally endangered species, and are native to the waters of the Missouri and lower Mississippi river systems.  They are one of the largest freshwater fish species in North America, and are uniquely adapted for living in large river systems.  Pallid sturgeon require large, turbid, free-flowing riverine habitat with rocky or sandy substrate to carry out their life functions.  They are well adapted to life on the bottom of the river and inhabit areas of swifter water than does the related (but smaller) shovelnose sturgeon.  The principle features distinguishing the pallid sturgeon from the darker shovelnose sturgeon is the absence of bony places on the belly.  Pallid sturgeon may reach lengths of over 5 feet, and weigh more than 80 pounds.  Pallid sturgeon require 15 years to reach sexual maturity, and may live to be 100 years old.  Although the exact dietary composition of pallid sturgeon is poorly understood, it is known that they are highly opportunistic bottom-feeders, and utilize a wide range of seasonal food items such as small baitfish, aquatic insects.  Habitat loss, river modification, and dam construction are all primarily blamed for the severe decline of the pallid sturgeon population.  Restoration efforts and scientific studies are currently underway in an attempt to better understand this prehistoric river fish.

Sauger (Sander canadensis)

The sauger is a close relative to the walleye, and both species are found in the Missouri River and are a highly prized game fish by recreational anglers.  Saugers are usually smaller than walleye, and will better tolerate more turbid water than will walleye.  For this reason, Sauger are often found in rivers where walleye are absent.  Sauger are easily distinguished from walleye by their distinctly spotted dorsal fin, patchy coloration, and absent white patch on the caudal fin (present on walleye).  Both walleye and sauger are found in the Missouri River, and it is not uncommon to catch a hybrid walleye/sauger cross, or "saugeye". 

Silver Carp (Hypophthalmichthys molitrix)

Silver carp (or Asian carp) are considered a highly invasive species that were imported to North America in the 1970's to control algae blooms in aquaculture and municipal wastewater treatment facilities.  Shortly after their importation, they escaped from captivity, and began to expand their range into many North American waterways.  Silver carp are filter feeders, and like the paddlefish, use gill rakers to filter phytoplankton, zooplankton, and detritus out of the water column.  Silver carp prefer standing or slow-flowing conditions such as impoundments or backwaters.   They have no stomach, and are believed to continually filter feed.  As a result, silver carp can grow very quickly, and reach weights of over 40 lbs.  Silver carp are commonly referred to as "flying carp" for their tendency to jump out of the water as high as ten feet when startled.  These "flying" carp may pose a severe risk to recreational boaters traveling at high speeds in an uncovered boat. 

Longnose Gar (Lepisosteus osseus)

Longnose gar are very prevalent in the Missouri River, and are easily identified by their long, narrow snouts filled with numerous rows of sharp teeth.  They have long, cylindrical-shaped bodies, and may grow to exceed 5 feet in length.  The largest longnose gar caught in the Missouri River was just over 16 lbs, and was caught in 1996.  Longnose gar live in a variety of lowland habitats, but prefer sluggish areas of large rivers, lakes, backwaters.  A unique adaptation of the longnose gar is its ability to survive in warm, low-oxygenated water.  During times of low oxygen, longnose gar can often be observed swimming just beneath the surface of the water, and "gulping" down air.  Longnose gar can survive indefinitely on aerial respiration alone, which makes them uniquely adapted to living in warm shallow backwater areas.  Long-nosed gar feed primarily on small baitfish, but have also been known to target aquatic invertebrates and small crustaceans.