Today, while watching a seemingly endless school of mullet swim past, one swam to the surface and jumped right out of the water. Once back under the surface, it fell in line with the others and continued swimming.
Often, when kayaking or canoeing among the mangroves, we turn our heads to the sound of something hitting the water to watch a mullet jump three more consecutive times, like a stone skipping across the water.
Along the coastal waters of the Gulf of Mexico jumping mullet (also called striped mullet, gray mullet, and flathead mullet) are a common sight. However, there is not consensus on why it happens.
Some studies (Hoese 1985, Shingles et al. 2005) suggest that mullet come to the surface to gulp atmospheric oxygen to supplement what they obtain from the water. Mullet are often found in conditions with low dissolved oxygen levels, and holding air in an organ at the back of their throat could help them stay active under these conditions.
However, in southwest Florida, Ospreys and Pelicans are both predators of mullet, and jumping would likely alert them to the presence of a meal. Often, mullet will roll in the water, flashing their silvery, white ventral surface, which also gives away their whereabouts to predators searching from above. And indeed, Domenici et al. 2007 found that mullet surface less often in the presence of aerial predators.
Some sources suggest that mullet jump out of the water to avoid predators, and it seems logical that if something is chasing you, you might leap haphazardly from the water, hopefully out of reach of the jaws at your tail. Other sources say that jumping out helps the mullet rid their gills of debris or parasites.
It might even cross your mind that they jump to catch a tasty insect meal for themselves, but this is unlikely since mullet feed mostly on detritus and algae.
The reason behind their unusual behavior is still one of the wonderful, small mysteries of science, and who knows, maybe mullet are just jumping for joy, or even to look at themselves in the water’s reflection on the way back down.
Check out this video of Jumping Mullet in Tarpon Springs, FL.