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Gulf sturgeon are large fish that weigh up to 200 pounds (91 kilograms). They live in Florida rivers during the summer months, after spending the winter in the seawater in the Gulf of Mexico. In Florida, they attract a lot of attention by their habit of jumping several feet out of the water and returning with a loud splash. Three different explanations for why sturgeon jump are often proposed.

Feeding

Some fish species jump out of the water to catch flying insects. There are certainly plenty of insects in the subtropical air of summertime Florida. Moreover the sturgeon jump most frequently in the early morning and evening when most freshwater fish feed. For these reasons, many people believe that the sturgeon are jumping to catch food in the same way that a trout jumps from the water to catch a fly.

Parasite removal

All animals have parasites, and many have evolved behaviors for getting rid of them. Fish have parasites that attach to their scales, so it seems reasonable to suppose that sturgeon jump to remove parasites. Indeed, not only do the sturgeon vigorously shake themselves in the air, they almost always hit the water with great force on their sides. This way of striking the water reinforces the idea that the sturgeon are trying to shake or knock off parasites.

Aggression

Every year a number of tourists riding in boats are injured when they are hit by jumping sturgeon. To the tourists this does not seem accidental. After all they are invading the sturgeon’s territory, and that is a circumstance that often provokes an animal to attack. Indeed the sturgeon jumping is most intense at the height of the tourist season, which to the tourists seems to confirm that they are the object of the sturgeon’s anger.

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