Tropical to temperate latitudes in the western Atlantic Ocean
Shallow coastal waters
Near Threatened With Extinction
Order Myliobatiformes (stingrays and relatives), Family Rhinopteridae (cownose rays)
Named for the shape of its head, which when observed from above resembles a cow’s nose, the cownose ray is a moderately sized stingray native to the western Atlantic Ocean. Like all eagle rays, cownose rays are active swimmers and are rarely found lying motionless on the seafloor like the closely related whiptail stingrays (e.g., southern stingray).
Cownose rays have a distinct shape with long, pointed pectoral fins or “wings” that are separated into two lobes at the front of their high-domed heads – creating the cow-nose shape. This species is a foraging predator that specializes on shelled, invertebrate prey including clams, snails, lobsters, oysters and crabs. Once cownose rays detect their prey, they flap their pectoral fins while also sucking up sediment through their mouths and out their gill slits. Eventually they draw the prey into their mouth and use their strong jaws and thick, crushing tooth plates to break open the shells. In some areas, experts hypothesize that large populations of cownose rays have contributed to the decimation of local shellfish populations, threatening fisheries that target those species.
Generally found in shallow marine and brackish coastal waters, cownose rays are also known to form large schools and migrate long distances. However, their migration patterns and reason for traveling such long distances (i.e. feeding or mating) are not fully understood. Adult cownose rays reach widths of approximately three feet (~1 m) and have few natural predators, though some large coastal sharks are known to attack and eat this species. Cownose rays are ovoviviparous, meaning eggs develop and are hatched within the body of the mother. Embryos live off of energy obtained from yolk sacs, and then later in their development are nourished by the uterine secretions of their mother. Only after the young are able to survive on their own does the mother give birth to her young. Generally, each female only produces one pup at a time.
Cownose rays have poisonous stingers, however, since they are shy and generally swim at the surface, they pose a minimal risk to humans stepping on their spine. Though cownose rays are not targeted in commercial fisheries, they are often captured accidentally in fisheries targeting other species. Some people have suggested a possible future fishery for this moderately common ray, which may have an adverse impact on their populations if not properly managed. Cownose rays are calm, graceful swimmers and are often featured in public engagement exhibits – such as touch tanks – in aquariums throughout their range. Experts consider this species ‘near threatened’ with extinction.
Check out KELP (Kids Environmental Lesson Plans) for free activities that teach children about the ocean.
Cownose rays on...