Length and age at maturity of Antarctic krill
Length and age at maturity of Antarctic krill
复制标题
南极磷虾的长度和成熟年龄
作者：
V. Siegel;V. Loeb
对南极半岛地区几次夏季考察航次的数据进行了分析，以计算南极磷虾的长度(L50)和成熟年龄。成熟时的长度L50被定义为50%的磷虾种群达到性成熟的长度。雌性磷虾的L50值为34.65-35.91 mm，是产卵旺季的最佳估计值。雄性在L50值为43.35-43.71 mm时达到性成熟较晚。磷虾成熟时的长度和第一次产卵时的长度是相同的。与平均年龄数据的比较表明，雌性在第三个生长季节成熟(年龄2+)，而雄性在第四年成熟(年龄3+)。男性和女性都表现出“刀锋般的成熟”。
Data from several summer research cruises in the Antarctic Peninsula region were analysed to calculate length (L50) and age at maturity for the Antarctic krill, Euphausia superba. Length at maturity L50 is defined as the length at which 50% of the krill stock attains sexual maturity. L50 values of 34.65–35.91 mm for female krill are the best estimates for the peak spawning season. Males attain sexual maturity later at L50 values of 43.35–43.71 mm. Length at maturity and length at first spawning are identical for krill. Comparisons with mean length-at-age data show that females mature in the third growth season (age class 2+), while males reach maturity in the fourth year (age class 3+). Both sexes show ‘knife-edge maturity’.