This beautiful stingray is one of the more common of 14 whiptail stingray species found in southern Africa. The upper surface of the blue stingray Dasyatis chrysonota is primarily brown or yellow-brown with mottled blue markings, while the underside of the animal is pale. This species has a pointed snout, and a single serrated spine along the whip-like tail. Blue stingrays reach a disc width of 75 cm, and at this stage can be between 20-25 kgs. Females reach sexual maturity at a size of 50.5 cm which is attained at an age of 7 years, while males reach sexual maturity at a size of 39.5 cm which is attained at an age of 5 years. Like humans, female blue stingrays have a gestation period of 9 months and give birth to live young. However, unlike humans where the fetus is attached to its mother by the umbilical cord, blue stingrays are ovoviparous which means embryos develop within egg cases inside the mother’s body. 1-7 young are birthed, averaging 17 cm in width, and are miniature replicates of the parents.
Written by: Minke Witteveen
For more reading:
• Branch, G.M., Griffiths, C.L., Branch, M.L. and Beckley, L.E. 2010. Two Oceans: A guide to the marine life of southern Africa. Pp. 262. Random House Struik Publishers, Cape Town.
• Cowley, P.D. 1997. Age and growth of the blue stingray Dasyatis chrysonota from the South-Eastern Cape coast of South Africa. South African Journal of Marine Science 18: 31-38.
• Ebert, D.A. and Cowley, P.D. 2009. Reproduction and embryonic development of the blue stingray, Dasyatis chrysonota, in southern African waters. Journal of the Marine Biological Association of the United Kingdom 89: 809-815.