Marine Research Institute, Skúlagata 4, P. O. Box 1390, 121 Reykjavík, Iceland.
J Fish Biol. 2011 Apr;78(4):1110-31. doi: 10.1111/j.1095-8649.2011.02923.x. Epub 2011 Mar 11.
The interaction between two species of gadoid and a shrimp stock was studied in a 40 km long two-armed fjord in north-west Iceland. On the basis of acoustic and trawl surveys in 2005 and 2006, immature cod Gadus morhua and haddock Melanogrammus aeglefinus were found to migrate to the inner part of the fjord in late summer, concurrent with rising temperatures. At the same time, the local northern shrimp Pandalus borealis stock retreated into the north-east arm of the fjord. Vertical distribution of acoustic targets indicated that a significant and temporally variable fraction of the gadoids was inaccessible to the trawl. Shrimp was a significant part of the diet of immature G. morhua, except in June 2006 when euphausiids comprised most of the diet of both G. morhua and M. aeglefinus. Shrimp was only a minor part of the diet of M. aeglefinus. An on-off relationship was observed in the catches of gadoids and shrimp. In hauls with large catches of gadoids, few shrimp were found and vice versa, indicating avoidance reaction at this spatial scale. The cooling in winter may have driven the gadoids to the outer parts of the fjord, which in turn may have aided in the dispersal of the shrimp stock in the following months.
在冰岛西北部一个 40 公里长的双臂峡湾中，研究了两种鳕鱼和一种对虾种群之间的相互作用。根据 2005 年和 2006 年的声学和拖网调查，未成熟的鳕鱼和黑线鳕在夏末随着温度的升高迁移到峡湾的内部。与此同时，当地的北方对虾种群退回到峡湾的东北臂。声学目标的垂直分布表明，拖网无法捕捞到大量的鳕鱼。除了 2006 年 6 月，磷虾构成了鳕鱼和黑线鳕大部分食物外，虾是未成熟鳕鱼的重要食物来源。虾只是黑线鳕食物的一小部分。鳕鱼和虾的捕捞量呈消长关系。在鳕鱼捕捞量大的渔获中，发现虾的数量很少，反之亦然，这表明在这种空间尺度上存在回避反应。冬季的降温可能促使鳕鱼游到峡湾的外部，这反过来可能有助于虾类资源在接下来的几个月中分散。
