What is a Cownose Ray?
The cownose ray is a type of marine fish which lives near North African and North American coastlines in the Atlantic ocean and throughout the Gulf of Mexico. Rays are distinctive fish with flat, kite-shaped bodies, which result from their wing-like fins and long, whip-like tails. One of 42 species of rays, the scientific name for the cownose ray is Rhinoptera bonasus.
Also called a cowfish or a skeete, the cownose ray derives its common name from its wide, squared nose. Its smooth skin is brown above and white below, and its tail spines, poisonous spikes common to all rays, are located near the base of the tail. These rays are usually about 36 inches (91.4 cm) in total width and can weight up to 50 pounds (22.7 kg).
A ray's teeth are actually flat plates located on its upper and lower jaws. The plates hold columns of teeth fitted together to make a whole. In the cownose ray, the plate has seven series, or columns, of teeth. Each series has 11-13 teeth, and teeth are either hexagonal, pentagonal, or tetragonal depending on their location on the plate.
Primarily feeding on bivalve mollusks, the ray's dental plates are ideal for crushing the hard shells of its desired food. Cownose rays also feed on some crustaceans and bony fish. To feed, these rays flap their wings against the sandy ocean floor to uncover their prey. This behavior is seen frequently in oyster beds and subsequently destroys the beds.
Breeding in June through October, cownose rays are oviviviparous, meaning the young is gestated inside eggs inside the female ray's body. Gestation is believed to last 11 to 12 months, and normally just one offspring, or pup, is born. The pup measures between 11-18 inches (28-45.7 cm) long at birth. Rays are thought to live 13-18 years.
The cownose ray is known for its long migrations. In late fall, schools of these rays will travel to the coasts in northern South America to live until late spring when they will return to their North American habitats. Schools are often large, some numbering in the millions, and rays stay in schools throughout the year.
Though the spines of all rays are poisonous, the cownose ray is not considered very dangerous to humans. These rays do not sit on the ocean floor as many other species do, so danger of stepping on them is almost eliminated. Also, since their tail spines are located near the base of their tails, the flicking of the tail that makes other rays dangerous is minimal. Care should still be taken around these animals, however, since it is possible to be hurt by the tail spines.
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