Shovelnose sturgeon are ancestral fishes.  They have survived relatively unchanged for millions of years in large, turbid rivers that were wild and unpredictable.  The rivers rose during the spring and early summer from snow melt and rain creating flood waters that covered the land, and washed rich nutrients back into the rivers.  Flooding also maintained river wetlands and backwater areas which are critical not only to ancestral fishes, but to many different species of terrestrial and aquatic life.  As the seasons progressed, the rivers dropped, exposing sand and gravel bars which created nesting habitat for migratory shorebirds, and other species of birds and wildlife.  The shallow sand and gravel substrate under the water created foraging and spawning habitat for many different species of aquatic life.

Today, the flows are regulated for navigation, irrigation, and flood control.  Dams and channelization have destroyed spawning, rearing, and foraging habitat for sturgeons, and many other fish species.  River wetlands have been drained for commercial development. Sediment is collecting at an accelerated rate because of poor land use practices.  Rivers have become a dumping zone for pollution.

The construction of dams for flood control and hydropower has reduced the river's natural turbity, lowered water temperatures, and restricted the natural flow of the river, thereby altering the conditions sturgeons need for successful spawning.  Dams have also isolated sturgeon populations, and in many instances, have blocked migration to ancestral spawning grounds.

Channelization, and bank stabilization for commercial navigation has eliminated oxbows, and other important backwater areas that sturgeons and other species use for rearing habitat.  Many of the shallow sand and gravel bars that were used for foraging and spawning have also been eliminated.

Pollution from industrial and agricultural run-off has had devastating effects on many species, including humans.  It is important to remember that rivers provide some of the fish we eat, and the water we drink, so when the ancient survivors like sturgeon and paddlefish are struggling to survive, we should all be concerned.

CURRENT DISTRIBUTION

HISTORY

Shovelnose sturgeons are the smallest and most abundant of the three river species. Historically, shovelnose sturgeons were found throughout most of the Mississippi and Missouri River basins, from Montana south to Louisiana, and from Pennsylvania west to New Mexico.  They presently have a more limited range due primarily to man's alteration of the rivers, and are no longer found in Pennsylvania, New Mexico, and large parts of Kansas, Kentucky, and Tennessee where they were once abundant.

BIOLOGY

Shovelnose sturgeon are potamodromous meaning they undertake regular migrations in large freshwater systems.  They can tolerate high turbidities typical of the muddy waters of the Missouri and Mississippi Rivers.  They prefer the strong currents of main river channels, and feed primarily on aquatic insects, mussels, worms, and crustaceans which are commonly found on sand or gravel bottoms. They have a torpedo shaped body, and flattened, shovel-like snout which helps them glide effortlessly along the bottom while searching for food.

The roe of the shovelnose makes an acceptable caviar, and their flesh is considered best when smoked.  Commerical overfishing has not been a major detriment to this species, perhaps because of their small size. The largest recorded shovelnose was approximately 35 inches (900mm) from head to tail, and weighed close to 8 pounds (3 - 4kg). 

In areas where old river habitat remains largely in tact, shovelnose sturgeons are abundant, and regulated fishing still occurs.

There are three North American species of the genera, Scaphirhyncus...

1. Alabama sturgeon, Scaphirhynchus suttkusi, an extremely rare species once clouded in controversy, and nearing extinction;
2. Pallid sturgeon, Scaphirhyncus albus, considered rare and quite vulnerable;
3. Shovelnose sturgeon, Schaphirhyncus platorynchus, the most common and widely distributed of the 8 North American species.

There is reason to believe there has been some hybridization of shovelnose sturgeon with both the pallid sturgeon, and Alabama sturgeon.