Tennessee Wildlife Resources Agency

TWRA's Region 4 - East Tennessee

Reservoir Fisheries Management Program

Shortnose Gar - Lepisosteus platostomus

(This page was last updated - 06/28/2007)

Scientific name: Lepisosteus platostomus (Lepid "scale", osteus "bony", platy "flat", stomus "mouth")

Common name: shortnose gar

shortnose gar
A Mississippi River shortnose gar - photo by Jim Negus

Species Overview

The shortnose gar is one of four species of gar found in Tennessee. They are restricted to the Mississippi and Cumberland River drainages of West Tennessee and within the Mississippi River basin of the Central United States.

The Tennessee state angling record taken from Kentucky Reservoir in 2001 weighed 6 pounds and 6 ounces. An 8 pound shortnose gar taken by archery from Chickamauga Reservoir in 1984 holds the non-sportfishing record.

Identification

All gars have torpedo-shaped bodies with the dorsal and anal fins located far back towards the tail. They are covered by thick ganoid scales that create a very hard protective covering.

The snout of a shortnose gar is very similar in shape to that of a spotted gar. A spotted gar's snout will have irregular blotches on the top and sides. These spots are absent from the snouts of shortnose gar.

The snouts of shortnose and spotted gar are not as broad as the snout of an alligator gar, and very dissimilar to the long, thin snouts of longnose gar. The minimum width of an alligator gar's snout will be contained 4.5 or fewer times in the snout length while that of other gars will be 5 or more times.

Alligator gar have two rows of "canine like" teeth on the upper jaw while other gars usually have only one row. Some shortnose gar will have a second row of short, prickly teeth on the upper jaw.

 

shortnose gar snout
The snout characteristic of a shortnose gar - photo by Jim Negus

Habits

Gars have a duct that connects their throat to a highly vascularized swim bladder that acts like a lung. This allows them to withstand very low oxygen levels. They are commonly observed gulping air at the surface on calm days.

Shortnose gar are perhaps a bit more tolerant of turbidity than our other gar species. The young feed on small crustaceans and insects, but quickly switch over to a diet of primarily fish. They are ambush predators and lie still in the water until an unsuspecting fish swims by. They lunge forward and lash their heads from side to side in order to capture prey. All four of Tennessee's gar spend much of the time lying still or swimming slowly near the surface.

Life Cycle

Spawning usually takes place in shallow, slack water during the spring over vegetation and submerged structures. Gar eggs are poisonous to humans.

Newly hatched gars have an adhesive disc on the underside of the snout which they use to attach to objects on the bottom until the yolk sac is absorbed. A dorsal caudal filament at the posterior end of their upturned vertebral column disappears when they mature.

 

shortnose gar
A Mississippi River shortnose gar - photo by Jim Negus

References

Etnier, D. and W. Starnes. 1993. The Fishes of Tennessee. The University of Tennessee Press.

 

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