Bowfin (Amia Calva) - Introduced

Male and female bowfins.

16-inch male (top) with tail eye-spot and female (bottom) bowfin from the Connecticut River. Note also the greenish fins on the male.

Identification. Long streamlined body. Tail asymmetrical. Bony plate on bottom of lower jaw. Large mouth with strong jaws and many sharp teeth. Long single dorsal fin with more than 42 soft rays. No spines. Tubelike nostrils. A dark spot at the upper base of the tail in juveniles and adult males. Dark olive to brown on back fading to cream color on belly. Young fish have dark reticulated patterns on sides. 

Bowfin gular plate.

Close-up of the bony plate on a bowfin lower jaw.

Size. Commonly 8 to 24 inches. State survey max. size 27 inches. Max. reported size 3.5 feet. World Record 21.5 pounds.

Distribution. Northeastern North America west to the Mississippi drainage. The only known populations in Connecticut are in Scoville Reservoir (Wolcott) and the Connecticut River, where they can be locally common in abundance.

Bowfin distribution map.

All maps created in 2009. See CT DEEP Fish Community Data for updated distributions.

Habits. Prefer slow-flowing, vegetated areas of lakes and rivers. A specially adapted air bladder allows them to breathe by gulping air at the surface, enabling them to live in stagnant swamps and backwaters.

Comments. Bowfin have occasionally been reported from the Connecticut River for many years, but they recently (2003) experienced a population expansion and are now common north of Hartford (recent captures indicated by red triangles on map). Wherever they are introduced, there is concern that this species may affect resident fish populations through competition or predation.

26 cm bowfin in a tank.

An 11-inch subadult bowfin has bold markings that will fade with adulthood.


Text and images adapted from Jacobs, R. P., O'Donnell, E. B., and Connecticut DEEP. (2009). A Pictorial Guide to Freshwater Fishes of Connecticut. Hartford, CT. Available for purchase at the DEEP Store.