Paddlefish Facts

A family of primitive fishes, paddlefishes (Polyodon spathula) are a group of ray-finned fishes with a characteristic paddle-like snout.

Also known as 'freshwater sharks', the paddlefish is an exclusive extant of North America. Paddlefish are endemic creatures that lived freely in the Mississippi River Basin and some parts of the Gulf Coast drainages before 1900.

The distribution of present paddlefish populations has a range limited to the tributaries of the Mississippi and Missouri rivers and the Mobile Bay Basin. They swim with their close-set gill rakers wide open to be able to catch microscopic plankton. The skeleton of a paddlefish is mostly cartilaginous, with a forked heterocercal caudal fin. The Chinese paddlefish (Psephurus gladius) were reported to have gone extinct in 2020, which was made official in 2022. It is known by many names like paddlefish sturgeon, spoonbill, Mississippi paddlefish, and albino paddlefish. The most distinguishable feature of this species is its long rostrum, an extension of the paddlefish skull or cranium. Cooking a tasty paddlefish dish is difficult because of its strong acidic flavor. Paddlefish caviar is known to have a nutty, balanced, and buttery-rich flavor, making it a popular delicacy.

To know more about aquatic creatures, you can also check out our articles on Frilled Shark facts and Blacktip Shark facts.

What type of animal is a paddlefish?

Paddlefishes, a member of the family Polyodontidae, are a group of fishes endemic to the United States. These fish are exclusively found in freshwater. The American paddlefish is known to have existed since the Paleocene period, around 65 million years ago. Unlike the long snout of other fishes, the rostrum of the paddlefish is not an extension of the upper and lower jaws but the skull. Paddlefish have a caudal fin that gives them an appearance similar to sharks. However, they are more closely related to surgeons and not sharks.

What class of animal does a paddlefish belong to?

American paddlefish (Polyodon spathula) belongs to the class Actinopterygii. This class of vertebrate fish is recognized by the presence of ray fins supported by bony spines, which are directly attached to the proximal and basal regions of the skeleton.

How many paddlefish are there in the world?

No exact data is available on the number of spoonbill paddlefish populations worldwide. The species belongs to the Vulnerable category, indicating that its limited population is moving towards being endangered. The last Chinese paddlefish was observed in the Yangtze River Basin in 2003

Where does a paddlefish live?

Paddlefish are native to the Mississippi River Basin and the neighboring drainage systems in the Gulf slope. Current paddlefish populations have a habitat limited to the tributaries of the Mississippi and Missouri rivers, along with the drainage system in Mobile Bay. After 1991, paddlefish were reintroduced in western Pennsylvania in the freshwater river systems of Ohio, Allegheny, and Monongahela. Paddlefish distribution covers a total of 22 U.S states, including Mississippi, Missouri, Ohio, Oklahoma, Alabama, and North Dakota.

What is a paddlefish's habitat?

Freshwaters are the natural habitat of paddlefish. These fishes commonly prefer deep water bodies with slow-moving currents. Before the 20th century, paddlefishes could be found in oxbow lakes, free-flowing and braided rivers, and backwater lakes of the Mississippi River Basin. They can also be found in bayous and the deep tailwaters below dams.

Who do paddlefish live with?

American paddlefish species can be found along with other fishes as they like to swim in a group.

How long does a paddlefish live?

American paddlefish have a life span of more than 30 years. The average range of their lifespan is 8-18 years, while dentary examination of some paddlefish indicates a possibility of individuals living for nearly 60 years.

How do they reproduce?

The reproductive cycle in American paddlefish is marked by the onset of late sexual maturity, both in the male and female members of the species. The female fishes reach maturity between the ages of 7-10 years, while for male members it is around the age of seven years. Paddlefishes migrate upstream when spring rains raise the water level from March to June. Here, the females release large amounts of eggs, and the males discharge substantial quantities of sperm, a process known as spawning. The spawning period in paddlefishes is noticed mostly around springtime because of an extended photoperiod and appropriate rise and flow in the water body. The spawn combines through external fertilization. Following fertilization, and an average incubation period of about seven days, the paddlefish eggs hatch, and the young ones are whisked downstream. Water temperatures need to be approximately 60°F (16 °C) for proper incubation to occur. Further development takes place in freshwater.

What is their conservation status?

According to the IUCN's (International Union for Conservation of Nature) Red List, the paddlefish species have been categorized under the conservation status of Vulnerable species. Human activities like overfishing increased the construction of dams, polluting their habitat, and poaching, along with zebra mussels infestation, are considered the main causes why American paddlefishes might soon become an endangered species.

What do paddlefish look like?

Spoonbill paddlefishes are a group of large fishes with the characteristic presence of blade-like snouts. The snout of a paddlefish is enveloped with electroreceptors. This feature is particularly beneficial for detecting zooplankton and makes up for the anatomically poor eyes possessed by these fishes. Paddlefishes have scale-less, smooth skin with small, laterally-pointed eyes. They have a large mouth with no teeth, a tapering operculum flap, and a heterocercal caudal fin. Paddlefish appear to be almost black or bluish-gray in color and have a white underbelly.

How cute are they?

This fish is cute enough to make you wonder how anyone had the heart to hunt them to the extent that they would become a Vulnerable species. With their small eyes and smooth skin, they look adorable. Since paddlefish are planktivorous fishes found in shallow waters, they are not dangerous to humans. However, the Chinese paddlefish were piscivorous, primarily feeding on small fish and crustaceans. If a live paddlefish is not handled properly, it will thrash around aggressively, hurting people.

How do they communicate?

The communication channels in paddlefishes mainly involve electrical, tactile, and visual sensations. The sensory receptors on the paddle-like snout of the fish work as an antenna to detect changes in electrical fields and collect impulses from the surrounding environment. The sensory impulses gathered by the paddlefishes benefit in migration, spawning, and tracing prey. Besides electrical reception, paddlefishes utilize their tactile and visual senses for communication while also being aided by the sensory pores covering nearly half of their skin surface.

How big is a paddlefish?

The average length of the members of the family Polyodontidae is known to be in the range of around 5-7 ft (1.52-2.13 m). They are smaller in size when compared to Chinese paddlefish.

How fast can a paddlefish swim?

The fastest a paddlefish can swim was recorded at 2.7 mph (4.3 kph). The speed may vary depending on the water's flow and other factors.

How much does a paddlefish weigh?

The average weight of a paddlefish is in the range of 40-100 lb (18.1-45.4 kg). However, in 1916 an American paddlefish was captured in West Okoboji Lake of Iowa that weighed more than 198 lb (89 kg) and is known to be one of the biggest American paddlefish to date. The largest Chinese paddlefish ever caught was nearly 23 ft (7 m) in length and weighed a few thousand pounds.

What are the male and female names of the species?

No distinct names are given to the members of this group based on their sex. The males are called male paddlefish while the females are referred to as female paddlefish.

What would you call a baby paddlefish?

The infants of the paddlefish are referred to as offspring, baby paddlefish, or juvenile paddlefish.

What do they eat?

The paddlefish diet includes zooplankton, which are tiny animals that can be found in freshwater and saltwater. Their close-set gill rakers are used for filter feeding. They can also feed on small insects, insect larvae, and small fish on rare occasions. They have specialized mouth and gill rakers adapted for filter feeding. They feed with their mouths open to force the water over their gill rakers, filtering out the water and capturing all the plankton.

Are they eaten by humans?

Humans not only eat paddlefish but their eggs are in very high demand as caviar. Humans find this variety of fish rather tasty and good to eat. Paddlefish are typically fired, grilled, or smoked, with some salt and pepper seasoning and a complimentary dressing. Removing the skin and all red meat and adequately rinsing the fish before cooking is essential. Marinating the fish beforehand to neutralize the strong acidic flavor can also help to make a more delicious dish of paddlefish.

Would they make a good pet?

One might get the urge to bring home a paddlefish to keep in their aquarium. However, it is suggested to avoid having a paddlefish as a pet as these fishes grow rather large and need a lot of space and food to grow. Keeping a paddlefish in a home aquarium as a pet fish might also lead to a damaged rostrum, which is rather sensitive. You can instead admire their beauty at a public aquarium.

Did you know...

Paddlefishes are known to possess snouts covered with electroreceptors. Compared to visual receptors, this trait is known to be beneficial in hunting. Paddlefish caviar is extremely popular as a delicacy amongst people all over the world. The oldest fossil of a paddlefish dates back to the Early Cretaceous period, approximately 125 million years ago, whereby the species of American paddlefish diverged nearly 68 million years ago. Some female paddlefishes are known to reach maturity at a far later phase of their life span, sometimes as late as 16-18 years of age. 

Why is the paddlefish special to the state of Missouri?

The paddlefish is a precious fish. It will intrigue you to know that the paddlefish is one of the oldest species of fish that still exists, and this is why they have always been of great interest to biological researchers from around the world. This fish species is valued not only for its flesh and eggs, which are eaten as caviar, a popular gourmet dish but also very popular as sports fish. Paddlefishes were designated as Missouri's official aquatic animal in 1997.

How to catch paddlefish

The paddlefish is not like most other fishes, which can be baited. As such, paddlefish fishing requires significant skill and patience. The paddlefish, which are relatively large, are supposed to be caught by using large three-part hook grappling hooks. The technique is called snagging, where you make a sudden, vigorous pull on the fishing line when any movement is felt. This makes the hooks pierce the flesh of the fish externally, without requiring it to swallow the hook using bait. Nets, pole hooks, and spears can also be used to fish paddlefish.

Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! Learn more about some other fish, including great white shark, or Caribbean reef sharks. You can even occupy yourself home by drawing on one of our swordfish coloring pages.