During the summer, many species migrate to Florida. One of the most notable species to Tampa Bay is the cownose ray (Rhinoptera bonasus). Don’t have a “cow” over these visitors, they are one of the least harmful rays to humans. Follow along for more about their biology and ecological significance!
Cownose rays are a cartilaginous fish, meaning that their skeleton is made of cartilage instead of bone. This species is dark brown on top and white underneath. They get their name from the distinct lobes on the front of their body that resemble a cow’s nose. Often, cownose rays are seen swimming just beneath the surface. Unlike other rays, they rarely rest on the bottom of the ocean, minimizing the potential to harm humans.
This pelagic species can be found in bays, rivers, estuaries and the open ocean. Their teeth are formulated for crushing mollusks and crustaceans, as well as other small invertebrates. While hunting, these rays will dig deep holes in the sand by moving their pectoral fins side to side and sucking up sand through their mouths at the same time. The sand collected will exit their gill slits, trapping their prey inside. A perfect example of how the form an animal takes fits the function of what they need to survive.
Annually, cownose rays migrate to Tampa Bay from early June throughout July. Thousands of this species will swim together in large groups known as “fevers.” As they swim, the wingtips of these rays often break the surface. This sometimes causes alarm for swimmers and divers that mistake them for shark fins. Occasionally, cownose rays may be seen launching out of the water before landing with a loud smack. Scientists believe this behavior is thought to be a territorial display. When enjoying our local beaches, stay alert for these amazing rays and witness this opportunity of a lifetime. A stunning sight to see!
Enjoy this summer season by learning about the various species that frequent the Tampa Bay area. To learn more about the cownose ray, visit the National Oceanic and Atmospheric Administration website!