Some Aspects of the Thorny Skate (Raja radiata Donovan, 1808) Reproductive Biology in NAFO Division 3N Regulatory Area

• Main Authors: Río-Iglesias, J.L. (José Luis) del, Junquera, S. (Susana)
• Format: Report
• Language: English
• Published: Centro Oceanográfico de Vigo 2001
• Subjects: North Atlantic; Northwest Atlantic
• Online Access: http://hdl.handle.net/10508/737

Thorny skate samples from August to December 2000 were examined to determine both sexes maturity stages, length at maturity and females potential fecundity. The size and number of the ovarian oocytes increase as the maturation progress. In fully mature ovaries the average number of developed eggs is between 40 and 45 and its final mean size is 12.5 mm. The minimum number of developing eggs per female found in the ovaries was 2 and the maximum 88. Very few females at either the capsule extrusion or other of the active uterine stages have been found. On the contrary most part of the adult males were at the fully mature stages, suggesting that the samples could be taken on a mating aggregation season. Using data from 1997, 1999 and 2000, both maturity ogives have been fitted. The females length at maturity obtained ranged between 60 and 54 cm and that of the males between 43 and 51 cm.