Common Name: Southern Stingray
Latin Name: Dasyatis americana
Family: Dasyatidae
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Range:
Tropical waters of the Western Atlantic, ranging from the Mid Atlantic United States to as far down as Brazil. Often found in the Caribbean and the Bahamas, as well as the Northern Gulf Mexico.


Coloration:
Typically brown, olive-green or gray dorsal surface to camouflage itself with the sea bed, and a white ventral belly.

Morphology:
Diamond-shaped body with wings that are used to propel itself along the ocean floor. Tail contains poisonous barbs used for defense, however are not fatal to humans. Eyes are located on top of the head, as are spiracles. These openings help the stingray to breath while lying on the sediment. Water enters through the spiracles and is excreted through the gills. Mouth is located on the ventral surface to enable effective feeding. Males are smaller than females, each respectively measuring 51 centimeters and 80 centimeters in disc-width at sexual maturity (1). Size of offspring are related to size of parents, averaging approximately 20 centimeters in disc width.

Reproductive Cycle:
Hard to distinguish because Southern Stingrays are hardly ever observed breeding in the wild. However, mating seems to follow a pattern of ‘close following, precopulatory biting, insertion/copulation, resting, and separation’ (2) In captivity, lasts between three to seven months, typically resulting in a litter of multiple offspring, ranging from 2-12 young. They are ovoviviparous, meaning that the egg develops within the mother and then hatches before she gives birth to live young. It is believed that they are polyandrous, with females mating with multiple males occasionally in succession.

Habitat:
Southern stingrays live on the ocean floor in shallow, tropical waters. They prefer sandy sediments and soft-bottomed areas. Often found among coral reefs and seagrass beds. They have also been associated with distinct cleaning stations where they are cleaned of parasite by other fish, such as wrasses and hogfish.

Ecology/ Interactions with other Species:
These animals live in inshore, tropical waters among the sandy or muddy bottoms. They are typically non-aggressive, despite the reputation they have for their painful stings. Their aversion to aggression is evidenced by the symbiotic relationship they maintain with the blue-headed wrasse. This cleaner fish eats any parasites from the stingray’s dorsal surface when it enters the wrasse’s “station.” They are found either in pairs or own their own, only aggregating in the summer months when they migrate to higher latitudes.

Diet:
The diet of the southern stingray is quite varied depending on the relative abundance of certain types of prey in its environment. They have been known to feed on small crustaceans, such as shrimp and crabs. However, they also eat small bony fishes, worms, certain species of mollusks, and lancelets. Their most common method of predation is flapping their diamond-shaped wings to disturb the sediment on the ocean floor and consuming the prey that it finds.

Personal Experience:
I observed a male southern stingray while snorkeling among the coral reef in Cahuita. It swam steadily among the ocean floor a few feet away from the coral. It seemed relatively undisturbed by the human presence, and showed no aggressive tendencies.

References:
1. Henningsen, A.D. (2000). Notes on Reproduction in the Southern Stingray, Dasyatis americana (Chondrichthyes: Dasyatidae), in a Captive Environment. Copeia 2000: 826-828.
2. Chapman, D.D. et al. (2003). Mating behavior of southern stingrays, Dasyatis americana (Dasyatidae). Environ Bio Fishes 68: 241-245.
3. Stokes, M. & Holland, N. (1992). Southern stingray (Dasyatis arnericana) feeding on lancelets (Branchiostoma floridae). Journal of Fish Biology 41:1041-1043