Gandra Miguel, Winkler Alexander C, Afonso Pedro, Abecasis David
Centre of Marine Sciences (CCMAR), University of the Algarve, Faro, Portugal.
Department of Ichthyology and Fisheries Science, Rhodes University, Makhanda, South Africa.
Mov Ecol. 2024 May 9;12(1):35. doi: 10.1186/s40462-024-00469-7.
The meagre, Argyrosomus regius, is a large coastal predatory fish inhabiting waters from the north-eastern Atlantic and Mediterranean Sea, where it is targeted by commercial and recreational fisheries. Previous genetic studies have found an unexpectedly high population differentiation not only between the Atlantic and the Mediterranean, but also along the Atlantic coast. However, the reasons underpinning this genetic barrier remained unclear. Likewise, even though the species is amongst the world's largest marine teleosts, knowledge about its movement ecology and migratory behaviour remains notably scarce, and primarily reliant on fisheries-dependent data.
In this study, we used a combination of acoustic telemetry and pop-up satellite archival tags to investigate the movements of 22 adult meagre (70-143 cm total length) along the Southwestern coast of the Iberian Peninsula.
Our results strongly suggest that the previously reported genetic differentiation is not maintained by limited adult dispersal/movement, as hypothesized. On the contrary, we documented some of the longest individual annual migrations ever recorded for a coastal teleost, up to > 2000 km, with frequent back-and-forth movements between the West and Southern Iberian coasts. Moreover, their detected regional movement patterns support the existence of a marked seasonal behavioural shift, with individuals being less active and moving to deeper waters during winter, and are consistent with spawning philopatry associated to their summer reproductive movements. Finally, we identified putative aggregation areas that may harbour important feeding/overwintering grounds.
These findings shed new light on the movement and behaviour patterns of meagre that may be of particular importance for the conservation and spatial management of this species throughout its range, and open the door to further research on functional connectivity.
军曹鱼是一种大型沿海掠食性鱼类，栖息于东北大西洋和地中海海域，是商业渔业和休闲渔业的捕捞对象。先前的遗传学研究发现，不仅在大西洋和地中海之间，而且在大西洋沿岸，该物种都存在出乎意料的高种群分化。然而，造成这种遗传屏障的原因仍不清楚。同样，尽管该物种是世界上最大的海洋硬骨鱼之一，但关于其运动生态学和洄游行为的知识仍然非常匮乏，主要依赖于渔业相关数据。
在本研究中，我们结合使用声学遥测和弹出式卫星档案标签，研究了22条成年军曹鱼（全长70 - 143厘米）在伊比利亚半岛西南海岸的活动情况。
我们的结果有力地表明，先前报道的遗传分化并非如假设的那样由成年个体有限的扩散/移动所维持。相反，我们记录到了一些沿海硬骨鱼有记录以来最长的个体年度洄游，长达2000多公里，它们在伊比利亚半岛西部和南部海岸之间频繁地来回移动。此外，检测到的区域运动模式支持存在明显的季节性行为转变，个体在冬季活动较少并向更深水域移动，这与它们夏季繁殖洄游相关的产卵洄游习性一致。最后，我们确定了可能蕴藏重要觅食/越冬地的假定聚集区域。
这些发现为军曹鱼的运动和行为模式提供了新的见解，这对于该物种在其整个分布范围内的保护和空间管理可能尤为重要，并为进一步研究功能连通性打开了大门。
