Timing and route of migration of mature female blue crabs in a tidal estuary

Information on migration patterns is critical to using no-take migratory corridors and marine reserves to protect the spawning stock of commercially exploited species. Both active and passive acoustic tracking methods quantified movement of commercially and ecologically important blue crabs in the White Oak River estuary, NC, USA. We targeted post-mating female crabs migrating down-estuary to oceanic spawning grounds. Crabs travelled approximately 14.1 km mainly in deeper channels and over 12–26 days from mating areas to spawning grounds. No crabs were detected migrating down-estuary in the autumn and only 30% were detected migrating down-estuary in spring. None of the crabs detected near spawning grounds were detected or recaptured back up-estuary, suggesting that they either (i) do not return to the estuary after a one to two week period in the spawning area or (ii) were captured by fishermen. The results from this study demonstrate that (1) acoustic transmitters coupled with passive ...迁徙模式相关数据，对于依托禁捕洄游通道与海洋保护区开展商业捕捞物种产卵种群的保护工作至关重要。本研究采用主动与被动声学追踪技术，对美国北卡罗来纳州怀特奥克河河口内兼具商业与生态价值的蓝蟹移动行为进行定量分析，研究对象为交配后顺河口向下洄游至海洋产卵场的雌性个体。蓝蟹从交配场抵达产卵场的迁移距离约14.1公里，主要穿行于深水区航道，迁移时长介于12至26天。秋季未监测到任何蓝蟹开展顺河口向下洄游行为，春季仅30%的个体被检出此类洄游。在产卵场附近被监测到的蓝蟹，既未被再次检测到逆流洄归河口，也未被重新捕获，这提示两种可能性：其一，在产卵场停留1至2周后，它们不再返回河口；其二，它们已被渔民捕捞。本研究结果表明：(1) 声学发射器与被动声学监测技术联用...