Ovarian development associated with first maturity in three Antarctic channichthyid species


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It has been known for some time that yolk deposition and final ovarian maturation were prolonged processes for many Antarctic fish. The adolescent phase in three species of channichthyid has been studied, based on an extensive series of samples over five seasons. Samples were obtained during a series of abundance estimation surveys on the shelf around South Georgia. Fish were measured, and sex and maturity stage determined from macroscopic examination of the gonads. It was found that for female Champsocephalus gunnari and Pseudochaenichthys georgianus the adolescent phase lasts <1 year but in Chaenocephalus aceratus it lasts for nearly 4 years.