Mollet, Henry .F. , O'Sullivan J.B., Welsh J.B., Ezcurra J.M., S. Greenwald S.A.
Monterey Bay Aquarium, 866 Cannery Row, Monterey CA 93940
Preliminary captive biology of the pelagic stingray, Dasyatis (Pteroplatytrygon) violacea
Growth and feeding rates of 19 pelagic stingrays, Dasyatis (Pteroplatytrygon) violacea were measured during 3 phases in 1995 and 1996.
1. Fifteen rays were fed 3 times a week (mean 1.24 %BW/day) in quaratine (T =17.8 C) frrom March 1 to Oct. 18, 1995. Growth rates (mean 10.2 cm/yr, 3.1 kg/yr), and conversion factors (mean 9.3%) were seasonal.
2. During a transition period, interactions between pelagic stingrays and sunfish Mola mola were studied in the Open Bay Water exhibit (4600 m3, T = 20C). Daily feeding was introduced to minimize rays biting molas.
3. Four females and 2 males were fed daily (mean 2.5 %bodymass/day) in quarantine (T = 20 C) from March 19 to Dec. 10, 1996. Females had larger growth rates (mean 19,5 cm/yr, 11.1 kg/yr) than males (mean 12.0 cm/yr, 3.1 kg/yr) and one female reached record size (83 cm diskwidth, 23 kg. Feedingg an growth rates were again seasonal. A stillborn litter, an aborted 5 cm diskwidth embryo, an eggcase with 7 infertile eggs, an empty eggcase suggested that sperm storage of over 1 year and likely mating in captivity. (Session 40, Sunday June 29 (1987) Savery 239, 11:00.