Latin american journal of aquatic research
On-line version ISSN 0718-560X
RAMIREZ-MOSQUEDA, Edith; PEREZ-JIMENEZ, Juan Carlos and MENDOZA-CARRANZA, Manuel. Reproductive parameters of the southern stingray Dasyatis americana in southern gulf of Mexico. Lat. Am. J. Aquat. Res. [online]. 2012, vol.40, n.2, pp.335-344. ISSN 0718-560X.
The southern stingray Dasyatis americana (Hildebrand & Schroeder, 1928) is the most landed elasmobranch by small-scale fleets in southern gulf of Mexico. However, little is known of its life history parameters in this region. In this study, a total of 900 specimens were collected from February 2006 to December 2008 to determine the reproductive parameters needed for population assessments by means of ecological risk assessments or demographic analysis. Results suggested that females of D. americana reproduce annually, with a gestation of 7-8 months. The reproductive cycle of females is asynchronous, with ovulation and parturition occurring throughout the year. Females and males matured at 764 and 517 mm disc width (DW50) respectively. D. americana has one of the highest fecundity among dasyatids, from 2 to 7 embryos, with a sex ratio of embryos of 1:1. A linear relationship between maternal DW and fecundity was estimated, the larger females contain more embryos. The status of the population of D. americana is a cause of concern in the southern gulf of Mexico due to its high frequency of capture in artisanal fisheries and its apparently low biological productivity.
Keywords : Dasyatis americana; disc width at maturity; reproductive cycle; fecundity; gulf of Mexico.