Macroscopic data of the field research obtained during fishing trips on board Spanish longliner "Tronio" in 2007-2011 were given. Gonadosomatic indices (GSI) of 823 Antarctic toothfish individuals from various SSRU in the Ross Sea were calculated. For one specimen with maximum observed weight of gonads (15.5 kg, GSI – 23.85 %), the individual absolute fecundity (IAF) and relative fecundity (RF) were calculated, which were 976000 eggs and 15 eggs/gram, accordingly.
Indexes of maturity rate of gonads on various grounds in the Ross Sea during the fishery season confirmed previous conclusions about significant extension of Antarctic toothfish spawning period.
According to our data, the maturity length of Antarctic toothfish males and females are different. Thus, females achieved 50 % of gonad maturity at length of 99-102 cm, and males - 102-105 cm. The pattern remained the same when determining 95 % of fish with mature gonads. Thus, 95 % of females with mature gonads were noted at length of 120-123 cm, and among males - at length of 123-126 cm. In our collections, we noted occurrence of females with maturing sexual products at length more than 81 cm, and males - more than 87 cm.
Data on reproduction biology of Dissostichus mawsoni from the Ross Sea (Statistical Subarea 88.1)
Numéro du document:
WG-FSA-11/04
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