Cownose ray
Encyclopedia
The cownose ray is a species of eagle ray
found throughout a large part of the western Atlantic and Caribbean
, from New England
, USA to southern Brazil
. Cownose rays grow rapidly, and male rays often reach about 35 inches (88.9 cm) in width and weigh 26 pounds (11.8 kg). Females typically reach 28 inches (71.1 cm) in width and weigh 36 pounds (16.3 kg).
A cownose ray is 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. When threatened the cownose ray can use the barb at the base of its tail to defend itself from the threat.
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.
s, oyster
s, hard clam
s 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.
in St. Petersburg, FL, home of the Tampa Bay Rays
, a Major League Baseball
franchise formerly nicknamed the "Devil Rays" until 2008
.
Eagle ray
The eagle rays are a group of cartilaginous fishes in the family Myliobatidae, consisting mostly of large species living in the open ocean rather than on the sea bottom....
found throughout a large part of the western Atlantic and Caribbean
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...
, from New England
New England
New England is a region in the northeastern corner of the United States consisting of the six states of Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, and Connecticut...
, USA to southern Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
. Cownose rays grow rapidly, and male rays often reach about 35 inches (88.9 cm) in width and weigh 26 pounds (11.8 kg). Females typically reach 28 inches (71.1 cm) in width and weigh 36 pounds (16.3 kg).
Gestation
The embryo grows within its mother with its wings folded over its body. Initially it is nourished by an egg yolk, although the uterine secretions of the mother nourish it later in its development. There is some dispute about the length of gestation. At full term the offspring is born live, exiting tail first.Size and Appearance
The cownose ray is 11 to 18 in (27.9 to 45.7 cm) in width at birth. A mature specimen can grow to 45 inches (1.1 m) in width, and weigh 50 pounds (22.7 kg) or more. There is some controversy over the size that a mature cownose ray can reach. A ray reaching a span of 84 inches has been recorded .A cownose ray is 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. When threatened the cownose ray can use the barb at the base of its tail to defend itself from the threat.
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.
Feeding Habits
The cownose ray feeds upon clamClam
The word "clam" can be applied to freshwater mussels, and other freshwater bivalves, as well as marine bivalves.In the United States, "clam" can be used in several different ways: one, as a general term covering all bivalve molluscs...
s, oyster
Oyster
The word oyster is used as a common name for a number of distinct groups of bivalve molluscs which live in marine or brackish habitats. The valves are highly calcified....
s, hard clam
Hard clam
The hard clam , also known as a quahog , round clam, or hard-shell clam, is an edible marine bivalve mollusk which is native to the eastern shores of North America, from Prince Edward Island to the Yucatán Peninsula...
s 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.
Aquariums
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. One of these such tanks is located next to the right field stands at Tropicana FieldTropicana Field
Tropicana Field is a domed stadium in St. Petersburg, Florida, which has been the home of Major League Baseball's Tampa Bay Rays since the team's inaugural season in 1998, when they were the Devil Rays. It has also served as the host stadium for the Beef 'O' Brady's Bowl, an NCAA-sanctioned college...
in St. Petersburg, FL, home of the Tampa Bay Rays
Tampa Bay Rays
The Tampa Bay Rays are a Major League Baseball team based in St. Petersburg, Florida. The Rays are a member of the Eastern Division of MLB's American League. Since their inception in , the club has played at Tropicana Field...
, a Major League Baseball
Major League Baseball
Major League Baseball is the highest level of professional baseball in the United States and Canada, consisting of teams that play in the National League and the American League...
franchise formerly nicknamed the "Devil Rays" until 2008
2008 in baseball
-Major League Baseball:* Regular Season Champions* World Series Champions – Philadelphia Phillies** American League Champions – Tampa Bay Rays** National League Champions – Philadelphia Phillies* Postseason – October 1 to October 29...
.