McBride R S, Johnson A K, Lindsay E K, Walsh H J, Richards R A
National Marine Fisheries Service, Northeast Fisheries Science Center, 166 Water Street, Woods Hole, MA 02543, U.S.A.
Living Marine Resources Cooperative Science Center, Department of Natural Sciences, University of Maryland Eastern Shore, Princess Anne, MD 21853, U.S.A.
J Fish Biol. 2017 May;90(5):1861-1882. doi: 10.1111/jfb.13272. Epub 2017 Feb 23.
To improve knowledge of goosefish Lophius americanus' reproductive biology, females were collected during 2009-2012 from the Mid-Atlantic Bight shelf region of the U.S. east coast. Batch fecundity increased with total length (L ), from 229 100 to 2 243 300 mature oocytes per female (L range: 55·5-112 cm; n = 54). This estimate of fecundity at L is lower than one derived from a sample collected during 1982-1985. Examination of whole oocyte diameters in different months indicated that L. americanus is a serial spawner, releasing more than one egg veil per spawning season, as suspected or observed for other Lophius species. Seasonality of spawning was evident from whole oocytes and gonad histology, and from larval fish surveys spanning the U.S. north-east shelf, and confirmed a protracted (c. 6 months) spawning period. Peak spawning activity progressed northward from spring to autumn. The population-level implications of these results were explored by estimating population reproductive potential (P ), which considered the value of both current and future per capita reproduction using decade-specific age structure and fecundity at length. P is now more than 50% lower compared with the historical period (1982-1985), a result of the lower proportions of large females and reduced fecundity across all sizes. Mechanisms that could explain this loss of stock productivity are fishing-induced size-age truncation or regime shifts in egg production caused by changes in energy density of common forage species.
为增进对美洲鮟鱇繁殖生物学的了解，于2009年至2012年期间在美国东海岸中大西洋浅滩区域采集了雌性美洲鮟鱇。每尾雌鱼的分批产卵量随全长（L）增加，从229100个成熟卵母细胞增至2243300个（L范围：55.5 - 112厘米；n = 54）。该全长下的产卵量估计值低于1982年至1985年采集样本得出的估计值。对不同月份的整个卵母细胞直径进行检查表明，美洲鮟鱇是分批产卵者，每个产卵季节释放不止一层卵膜，这与其他鮟鱇属物种的推测或观察结果一致。从整个卵母细胞、性腺组织学以及横跨美国东北大陆架的幼鱼调查中都明显看出产卵的季节性，并证实产卵期持续较长（约6个月）。产卵高峰活动从春季到秋季向北推进。通过估计种群繁殖潜力（P）来探讨这些结果对种群水平的影响，该估计考虑了使用特定十年的年龄结构和全长产卵量来计算当前和未来人均繁殖的价值。与历史时期（1982 - 1985年）相比，P现在降低了50%以上，这是由于大型雌鱼比例降低以及所有尺寸的产卵量减少所致。可能解释这种种群生产力损失的机制是捕捞导致的大小 - 年龄截断，或者是常见饵料物种能量密度变化引起的产卵量的生态变化。
