“Right HERE, 11 o’clock, Rollers!” is hissed by a guide on the poling platform of his skiff. An eager angler perches on the bow, waiting for his shot as a string of rolling fish eases closer—80 feet, 70 feet, 60, 50—they’re in range. If you’ve ever stood on the front of a skiff waiting for tarpon, the sight of rolling fish gets your adrenaline pumping. It’s the visual cue we all wait for, you’re in the right spot, and the fish lets you know that with a brief glimpse of silver and a stare down through alien-like eyes.
The image of a rolling tarpon is the pinnacle of saltwater fly fishing. It draws countless anglers to the Florida Keys every year, and saltwater fly fishing in general. But why do tarpon roll?
Why Tarpon Roll
Tarpon are what is known as facultative air breathers. In layman’s terms, this means they can breathe through their gills or breathe air. They are able to do this through a specialized swim bladder. In most fish, the swim bladder is a balloon-like organ used to adjust buoyancy and stay upright. If you’ve ever seen a fish in a tank struggle to stay upright, chances are they have a swim bladder issue. Tarpon, on the other hand, have a specialized swim bladder that acts as a lung. This specialized swim bladder enables tarpon to gulp air and absorb it just as they would get oxygen from their gills.
In low-oxygen areas, rolling for air is how tarpon are able to stay alive. On flat, calm days, this explains why you see more tarpon rolling. The calm water’s surface reduces the amount of oxygen available in the water, resulting in more rolling fish. While this is the main reason tarpon roll, they also gulp air to regulate their buoyancy.
Since their swim bladders rely on gulping air, so does their buoyancy. If you watch a tarpon roll closely, you’ll notice the little air bubbles it leaves behind. These air bubbles are the tarpon releasing extra air to maintain the proper level of buoyancy to swim. These reasons account for the science behind tarpon rolling, but the third reason is out of imitation.
Tarpon are fairly social creatures and are often found in schools, sometimes numbering in the hundreds. When one tarpon rolls, it’s not uncommon for others to follow suit even tho they don’t necessarily have to roll. So if you see a tarpon roll, chances are there are more following behind that will likely join in on the behavior.
As mysterious as they are big, biologists are always learning more about tarpon. Organizations like Bonefish & Tarpon Trust are leading the way in tarpon research, constantly making new discoveries about tarpon. While these reasons for why tarpon roll are widely accepted, you never know what we’ll find out about these prehistoric creatures next.
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