Data from: 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 (WOR) estuary, North Carolina, USA. We targeted post-mating female crabs migrating down-estuary to oceanic spawning grounds. Crabs traveled ~ 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 fall 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 1-2 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 acoustic receivers provided reliable and valuable data on migration patterns of mature female blue crabs, and (2) mature female blue crabs are capable of migrating primarily within deep channels to spawning grounds shortly after insemination.迁徙模式相关信息，对于利用禁捕洄游通道与海洋保护区保护商业捕捞物种的产卵种群至关重要。本研究采用主动声学追踪（active acoustic tracking）与被动声学追踪（passive acoustic tracking）技术，量化了美国北卡罗来纳州白橡河（White Oak River, WOR）河口内兼具商业与生态价值的蓝蟹（blue crabs）的移动规律，研究对象为交配后向下游洄游至海洋产卵场的雌性蓝蟹。蓝蟹从交配区域前往产卵场的迁移距离约为14.1公里，主要行进于深水道中，耗时12至26天不等。秋季未观测到任何蓝蟹开展下游洄游，春季仅30%的个体被观测到此类行为。在产卵场附近被检测到的蓝蟹，均未被再次观测到或重捕至溯河上游区域，这提示存在两种可能性：其一，蓝蟹在产卵场停留1至2周后不会返回河口；其二，它们已被渔民捕获。本研究结果表明：其一，声学发射机（acoustic transmitters）与被动声学接收器（passive acoustic receivers）的组合可为成熟雌性蓝蟹的迁徙模式提供可靠且极具价值的数据；其二，成熟雌性蓝蟹可在授精（insemination）后短期内，主要沿深水道向产卵场洄游。