Spatial pattern of distribution and reproductive strategy of vermiculate electric-rays Narcine vermiculatus
Por:
Torres-Huerta A.M., Cruz-Martínez A., Ramírez-Chávez E.J.
Ahead of Print:
1 ene 2021
Resumen:
In the study, the authors evaluate the spatial distribution pattern of vermiculate electric-ray Narcine vermiculatus using geostatistical techniques to predict its spatial distribution and indicate its reproduction strategy. From January 2008 to December 2009, 3333 specimens of vermiculate electric-ray were caught. Total length (LT), sex, maturity stage, catch location and depth were recorded for each specimen. The LT of vermiculate electric-ray ranged from 6.7–24.6 cm. The authors estimate an irregular spatial structure, with a high-density patch ((Formula presented.) 53 ind. ha-1) located on the east coast, which concentrates 65.2% of the specimens. The high-density patch consists mainly of large juveniles (13.3–19.5 cm LT), sub-adults (14.0–19.8 cm LT) and young adults (14.7–21.3 cm LT). Data indicate that adults migrate to the high-density patch to reproduce. Males reached maturity at 14.5 cm LT, whereas females reached maturity at 19.3 cm LT. Vitellogenesis in female vermiculate electric-ray begins in June; ovulation, mating, fertilization and gestation in October and birth begins in February. This indicates an annual cycle with vitellogenesis and consecutive gestation, in females synchronized in reproduction. Fecundity was 1–8 ((Formula presented.) 4), and the sex ratio of embryos was 1:1. The birth occurred between February and April, with an average size at parturition of 6.3 cm LT. Incidental capture of sub-adults and adults of N. vermiculatus by bottom trawls threatens the survival of this species. © 2021 Fisheries Society of the British Isles.
Filiaciones:
Torres-Huerta A.M.:
Instituto de Recursos, Universidad del Mar, Puerto Ángel, Mexico
Cruz-Martínez A.:
Departamento de Ciencias Ambientales, Universidad Autónoma Metropolitana, Unidad Lerma, Lerma de Villada, Mexico
Ramírez-Chávez E.J.:
Instituto de Ecología, Universidad del Mar, Puerto Ángel, Mexico
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