Family: Polyodontidae
Common Family: The Paddlefish Family
Common Name: Paddlefish
Scientific Name: Polyodon spathula
Ecological Description/Identification
The American paddlefish is the largest fish species inhabiting West Virginia’s waters, sometimes reaching 5 feet in length. Paddlefish are native to the Mississippi River Basin, and they were once considered extirpated from West Virginia waters. However, they can now be found in the Ohio and Kanawha rivers and their tributaries, owing to a large-scale restoration effort by WVDNR. Paddlefish are easily distinguished by their long paddle-shaped rostrum and shark-like appearance. They are a large fish without scales, bluish-gray in color with small eyes and an elongated opercle flap over their gills. Paddlefish skeletons are almost entirely compose of cartilage. They can live in excess of thirty years.
Habitat
Paddlefish prefer slower moving, open-water and side channel habitats of large rivers. Their diet consists primarily of zooplankton, but they can consume other small insects and fish. They have a large mouth with no teeth. Paddlefish feed by swimming with their mouths open forcing large quantities of water over their gills that have large comb-like rakers designed to filter out plankton and other appropriate size forage items. The rostrum is an extension of the cranium, and both contain receptors that aid in detecting plankton swarms in the water column.
Conservation Issues
Paddlefish migrate long distances upstream to spawn, and they prefer silt-free gravel bars. Paddlefish spawn in the spring. Females do not begin spawning until they are seven to ten years old, and they will only spawn when ideal water temperature (55-60 degrees), photoperiod and rising river flow conditions all occur at the same time. Should this delicate balance of environmental triggers be disrupted, spawning can remain unsuccessful for many years. Construction of dams in naturally flowing rivers limits migration and frequently alters critical spawning habitats.
In addition to construction of dams and declining water quality impacting Paddlefish populations, they are targeted for the eggs to make caviar.
Facts
Paddlefish are still considered a species of conservation concern in West Virginia, therefore no angling for paddlefish is currently allowed. The West Virginia DNR is conducting a restoration project for this great river species through stocking and population assessments.
Similar Species
Paddlefish are closely related to sturgeon species.