The Cownose Rays feed on clams, oysters, hard clams and other invertebrates. By swimming in groups and flapping their wings at the same time across the seabed, they have learnt to stir up the loose sediment. This exposes buried clams and oysters and gives each Cownose Ray a tasty feast. The ray devours its catch using two modified fins on its front side which produce suction and draw food into its mouth. The food is then crushed by powerful dental plates, which make light work of even the toughest clams.
Cownose Rays can be found in both the Atlantic and the Caribbean Ocean, from New England in the USA right down to the southernmost part of Brazil’s east coast. They can be found in bays, estuaries and river mouths as well as the open ocean and migrate seasonally along the US coast from the Gulf of Mexico.
The rays are typically brown or olive-backed with a whitish or yellowish belly. Although its coloration is not especially distinctive, the shape of these brilliant creatures make them easy to recognise. It has a broad head with wide-set eyes and a pair of distinctive lobes on its subrostral fin. But of course it is most renowned for its wings which it uses to glide gracefully through the water. Their wings also give the rays their distinctive kite-like shape.
When attacked, Cownose Rays have a stinger which they use for self-defence. It’s called a spine and it’s located at the base of the Cownose Ray’s tail. This spine has teeth lining its lateral edges, and is coated with a weak venom which causes symptoms similar to that of a bee sting.
The reproduction cycle of the Cownose Rays is pretty rare and a single ‘pup’ is born to each female around mid-summer. Once impregnated, the embryo grows within its mother with its wings folded over its body. Initially it is nourished by a yolk-like substance, although the mother’s uterine secretions keep it healthy during the latter stages of development.
Unlike most other sea creatures, Cownose rays give birth to live young. The pup exits the mother tail first and is usually between 11 and 18 inches long. Females are usually impregnated again around 10 days after birth. The young grow rapidly and mature rays can have a wingspan as large as three feet, weighing up to 50 pounds. Though most are slightly smaller, weighing around 35 pounds.