Like gars, bowfin are bimodal breathers which means they have the capacity to breathe both water and air. Their gills exchange gases in the water allowing them to exploit oxygen for breathing, but they also have a gas bladder that serves to maintain buoyancy, and also allows them to breathe air by means of a small pneumatic duct connected from the foregut to the gas bladder. They can break the surface to gulp air, which allows them to survive conditions of aquatic hypoxia that would be lethal to most other species.