Spatial and temporal distribution of anadromous alewife (Alosa pseudoharengus Wilson) spawning and nursery habitats were determined by sampling in the Mullica River – Great Bay watershed (New Jersey, USA) in a combination of long- and short-term observational and quantitative studies. Reproduction was confirmed by examination of developing gonads, visual observations of spawning, and egg collections. Spawning typically lasted 2–4 days in discrete waves in freshwater tributaries from late March to late April. Nursery habitats for larvae and young-of-the-year alewife included low-salinity tributaries near the freshwater-saltwater interface and high salinity waters through early fall before departure to the ocean in late fall. Predation on eggs by fish predators, especially American eel (Anguilla rostrata Lesueur), occurred below a dam. This predation was also observed in the laboratory on eggs and larvae. These findings point out that this dam provided for enhanced predation on alewife early life history stages, and may cause an ecological hotspot for predation-prey interactions for this anadromous species and its catadromous predator.

中文翻译：

---

哨兵河口的 Alewife (Alosa pseudoharengus) 产卵和育苗区：空间和时间模式

溯河 alewife (Alosa pseudoharengus Wilson) 产卵和育苗栖息地的时空分布是通过在穆利卡河 - 大湾流域（新泽西州，美国）结合长期和短期观察和定量研究确定的。通过检查发育中的性腺、产卵的视觉观察和卵收集来确认繁殖。从 3 月下旬到 4 月下旬，在淡水支流的离散波浪中产卵通常持续 2-4 天。幼虫和一年中幼鱼的苗圃栖息地包括淡水 - 咸水界面附近的低盐度支流和初秋的高盐度水域，然后在深秋离开海洋。鱼类捕食者，尤其是美洲鳗 (Anguilla rostrata Lesueur) 对卵的捕食发生在大坝下方。在实验室对卵和幼虫也观察到了这种捕食。这些发现指出，这座大坝为 alewife 早期生活史阶段提供了增强的捕食，并可能为这种溯河物种及其溯河捕食者的捕食-猎物相互作用提供生态热点。