The study characterized the structure of juveniles and sub-adults of Farfantepenaeus brasiliensis and F. paulensis in the Cananéia-Iguape estuarine lagoon system and its adjacent coastal area by evaluating the period of juvenile recruitment, sex ratio, growth, longevity, natural mortality, and development time until the late juvenile phase. Samples were collected from July 2012 to June 2014. Shrimps were identified by species and sex, and measured (carapace length – CL mm); 889 individuals of F. brasiliensis and 848 of F. paulensis were analysed. Females were more abundant than males for both species. The growth parameters of F. brasiliensis were: CL∞ = 45.5 mm, k = 1.8 year−1 for males and CL∞ = 55.2 mm, k = 1.6 year−1 for females; longevity of 2.52 years (males) and 2.88 years (females); and natural mortality of 1.71 (males) and 1.55 (females). For F. paulensis, the following values were observed: CL∞ = 40.7 mm, k = 2.3 year−1 for males and CL∞ = 56.5 mm, k = 1.9 year−1 for females; longevity of 2.04 years (males) and 2.37 years (females); and natural mortality of 2.39 (males) and 2.05 (females). The juvenile recruitment of both species peaked in January 2014. The development time until late juvenile phase was ~7 months (F. brasiliensis) and ~5 months (F. paulensis). Even though the highest abundance of juveniles did not occur in the closed season, fishing is forbidden in the estuarine area and the migration towards the adult population occurred close to or even during the closed season.

中文翻译：

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巴西东南海岸卡纳内亚河口邻近海域粉虾幼虾 Farfantepenaeus brasiliensis 和 F. paulensis 的大小分布变化

该研究描述了青少年和亚成体的结构巴西远对虾和F. paulensis在 Cananéia-Iguape 河口泻湖系统及其邻近沿海地区，通过评估幼体招募期、性别比、生长、寿命、自然死亡率和发育时间直到幼体后期。样本于 2012 年 7 月至 2014 年 6 月期间采集。虾按物种和性别进行鉴定，并进行测量（甲壳长度 - CL mm）；889人F. brasiliensis和 848 个F. paulensis进行了分析。这两个物种的雌性都比雄性多。生长参数F. brasiliensis分别是：CL∞= 45.5 毫米，ķ= 1.8 年-1男性和 CL∞= 55.2 毫米，ķ= 1.6 年-1对于女性；2.52岁（男性）和2.88岁（女性）的寿命；自然死亡率为 1.71（男性）和 1.55（女性）。为了F. paulensis，观察到以下值：CL∞= 40.7 毫米，ķ= 2.3 年-1男性和 CL∞= 56.5 毫米，ķ= 1.9 年-1对于女性；2.04岁（男性）和2.37岁（女性）的寿命；自然死亡率为 2.39（男性）和 2.05（女性）。这两个物种的幼年招募在 2014 年 1 月达到顶峰。直到幼年后期的发育时间约为 7 个月（F. brasiliensis) 和 ~5 个月 (F. paulensis）。尽管幼鱼的最高丰度并未出现在封闭季节，但河口地区禁止捕鱼，并且接近或什至在封闭季节向成年种群迁移。