三重県英虞湾におけるギンポの成熟と産卵〔英文〕

概要

論文の詳細を見る
The present report deals with the reproductive biology of the tidepool gunnel Pholis nebulosa (Pisces: Pholididae) with particular reference to the morphology of the gonads, seasonal cycle of gonadal maturation, breeding season, size and age at the first sexual maturity, fertility, and sex ratio, based on 355 individuals taken from Ago Bay during the period from April 1980 to May 1982. The testis was bilobed, but the ovary was monolobed in shape. Vitellogenic oocytes in the ovaries and spermatozoa in the testes were present during the period from October to December. Spawning generally began in late November and ended in late December. The minimum sizes at the first maturity for females and males were 15 and 16cm in total length (TL), respectively. The ages of the fish at these sizes were estimated to be age 2 for both sexes. A female spawned only one time in a breeding season. The fertility (F) could be represented by the number of vitellogenic oocytes in the ovary, and it was expressed by the following equation: F=638TL-8672. The sex ratio varied significantly from 1:1 (P<0.01) in favor of females (56.9%).
日本水産學會の論文