Bowfin
The bowfin is a unique freshwater fish belonging to the family Amiidae and is the only species in its family, scientifically known as Amia calva. This fish is characterized by its long, stout body, olive skin, and distinctive dorsal fin that gives it its name. Bowfins are resilient creatures, capable of surviving outside water for up to one day due to their specialized air bladder, which functions like a lung, allowing them to thrive in oxygen-poor environments. They inhabit shallow, weedy lakes, slow-moving rivers, and swamps primarily in the eastern United States.
Bowfins exhibit a diverse diet, feeding on various fish, frogs, and aquatic invertebrates, making them effective predators in their ecosystems. Their spawning season occurs from April to June, during which males create and guard nests where females lay up to 30,000 eggs. Despite their ecological significance, bowfins are often viewed unfavorably by sport fishermen due to their taste and predation on popular game fish. With an average lifespan of 10 to 12 years, bowfins continue to play a vital role in their natural habitats.
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Bowfin
Bowfins are the only member in their family and are named for the shape of their dorsal (back) fin. The bowfin is able to survive for one day outside the water because of its special air bladder. It may also be able to survive dry conditions by aestivating, which is similar to hibernating in the summer. In the north the bowfin is called a dogfish, and in the south it is called a grindle. Other names are grinnel and cypress trout.
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Ammiformes
Family: Amiidae
Genus: Amia
Species: Calva
The bowfin lives in shallow, weedy lakes, slow-moving rivers, and swamps across much of the eastern United States. This fish has olive skin on its long, stout body with dark markings. Males have a dark spot surrounded by an orange-yellow ring at the base of their rounded tails. Females do not have this ring or may not have the spot. Along the bottom side of the bowfin are its large anal fin, small pelvic fin, and pectoral fins. An adult bowfin grows to an length between 20 and 28 inches (50 to 70 centimeters) and weigh an average of one to five pounds (1/2 to 2 1/4 kilograms), although there are reports of fish weighing up to 20 pounds (nine kilograms).
The bowfin has a special air bladder which it can use as if it were a lung. This air sac inside the fish allows it to live in stagnant, swampy water where there is less oxygen and where other fish cannot live as well. The air bladder also enables the bowfin to survive up to one day out of water. During dry conditions, the bowfin may aestivate, which is similar to hibernation except that it is done in the summer. The bowfin is able to slow its bodily systems to conserve energy so that it can live longer when there is less water and food.
The bowfin receives its name from the long, undulating, or waving, dorsal fin which runs along the back side of its round body. The waving motion of the fin allows the fish to remain still in one place as it waits for prey to swim in front of its large, blunt head and waiting mouth. The diet of the bowfin consists of a variety of fish, such as sunfish, perch, minnows, bass, pike, and catfish. Because it does not taste good and also eats sport fish, the bowfin is quite unpopular with sport fishermen and conservationists. Other prey that this powerful and fast swimmer catches are frogs, shrimp, crayfish, and aquatic insects.
Spawning is the time when a female fish lays her eggs and the male fertilizes them. For bowfin, this occurs between April and June, the exact time depending on water temperature in various locations. The spawning grounds are in still bays and inlets where there is vegetation. The male clears a nest site one to two feet (30 to 60 centimeters) across by snipping off grass and weeds and letting them float away. At night, the female lays her 30,000 eggs on the soft sand, gravel, and roots of vegetation. More than one female lays her eggs in the nest, which the male guards for 8 to 10 days after he fertilizes them. The young hatch and attach themselves to the plant roots or lie on the bottom until they are 1/2 inches (around one centimeter) long. The male continues to guard them and to lead away intruders. He does this by swimming away noisily, expecting the intruder to follow him. The school of young fish swim after the male and begin feeding nine days after birth. When they are 1 1/2 inches (about four centimeters) long, they are independent of the male, and they leave the school when they are four inches (10 centimeters) long.
The bowfin is the only member in its family. Other names for it are dogfish, grindle, grinnel, and cypress trout.
The bowfin has an average lifespan of 10 to 12 years.
Bibliography
“Bowfin Fish: #1 Best Guide to Bowfin Fish in North America.” Bass Fishing - The Complete Guide, 19 Oct. 2023, bassonline.com/freshwater-species/bowfin/. Accessed 29 Mar. 2024.
“Bowfin.” A-Z Animals, 5 Oct. 2023, a-z-animals.com/animals/bowfin/. Accessed 29 Mar. 2024.