effect of hitting shock on the hatching of drifting fish egg

The drifting fish eggs are more likely to collide with ships, rocks etc. as they hatch while migrating through the river. For fish resources protection and waterway management, it’s important to clarify the upper threshold of hitting velocity and the effect of the hitting shock on their hatching. Thus, natural spawned and domesticated fish eggs were studied and compared. The effects of hitting objects, hitting velocity and the developmental level of the fish eggs on their hatching was also studied. The developmental stage was the most sensitive factor to hitting shock. Almost 70% of natural spawned semi-buoyant fish eggs can’t hatch successfully when the hitting velocity was 4.4 m s-1 and collided with rock, and this hatching rate was about 10%-30% higher than that of farmed ones at the same conditions.

漂流中的鱼卵在河道洄游孵化期间，更易与船舶、礁石等发生碰撞。为保护鱼类资源并开展航道管理，明确碰撞速度的上限阈值以及碰撞冲击对鱼卵孵化的影响具有重要意义。为此，本研究对天然产卵鱼卵与人工繁育鱼卵开展了对比研究，同时探究了碰撞对象、碰撞速度以及鱼卵发育阶段对其孵化效果的影响。研究表明，鱼卵发育阶段是对碰撞冲击最为敏感的影响因素。当碰撞速度为4.4 m·s⁻¹且与礁石发生碰撞时，约70%的天然产卵半浮性鱼卵无法成功孵化，该孵化成功率较相同条件下的人工繁育鱼卵高出10%~30%。