Skip Navigation

Species Search:
FieldGuidesthreatened and/or endangered search resultsthreatened and/or endangered

previous  | next

Cownose Ray Rhinoptera bonasus


enlarge +

Cownose Ray
credit: Dorothy Birch/CCSA

All Images


Get Our Newsletters


Advanced Search

Family: Myliobatidae, Eagle Rays view all from this family

Description Typically brown-backed with a whitish or yellowish belly. Although its coloration is not particularly distinctive, its shape is easily recognizable. It has a broad head with wide-set eyes, and a pair of distinctive lobes on its subrostral fin. It also has a set of dental plates designed for crushing clams and oyster shells. There are a series of canine teeth that are hidden behind the dental plates. Cownose rays grow rapidly, and male rays often reach about 35 inches (89 cm) in width and weigh 26 pounds (12 kg). Females typically reach 28 inches (71 cm) in width and weigh 36 pounds (16 kg).

A cownose ray has a stinger, called a spine, on its tail, close to the ray's body. This spine has teeth lining its lateral edges, and is coated with a weak venom that which causes symptoms similar to that of a bee sting.

Dimensions Up to 3' (91 m) wide.

Warning These rays have venomous tail spines that make them potentially dangerous.

Habitat Ocean or bay shallows.

Range Most of the western Atlantic and Caribbean, from New England, USA to southern Brazil.

Discussion Cownose ray feeds upon clams, oysters, hard clams and other invertebrates. It uses two modified fins on its front side to produce suction, which allows it to draw food into its mouth, where it crushes its food with its dental plates. Cownose rays typically swim in groups, which allows them to use their synchronized wing flaps to stir up sediment and expose buried clams and oysters. Cownose rays may be seen in selected zoo aquariums and often featured in special 'touch tanks' where visitors can reach into a wide but shallow pool containing the fish which have had their barbs pinched or taken off, making them safe enough to touch.