Senckenberg Institute, Department for Marine Research, Südstrand 40, 26382 Wilhelmshaven, Germany.
J Fish Biol. 2012 Jun;80(7):2571-94. doi: 10.1111/j.1095-8649.2012.03309.x. Epub 2012 May 4.
The diets of two non-commercial flatfish species (solenette Buglossidium luteum and scaldfish Arnoglossus laterna) and two commercial flatfish species (dab Limanda limanda and plaice Pleuronectes platessa) were compared in a study area in the German Bight (southern North Sea) to investigate prey-resource partitioning between these species. The diets of A. laterna and B. luteum mainly comprised crustaceans (harpacticoids, amphipods, cumaceans and decapods), whereas the diet of L. limanda and P. platessa consisted mainly of polychaetes. The Schoener index, calculated for different fish size classes between these flatfish species, showed a biologically significant diet overlap between small-sized L. limanda and P. platessa and B. luteum and A. laterna, using similar prey resources of smaller prey (e.g. amphipods, harpacticoids and juvenile bivalves). In contrast, with increasing body size, a change in the diet of L. limanda and P. platessa towards larger prey occurred (e.g. polychaetes and decapods), resulting in low diet overlap values with B. luteum and A. laterna. Due to these size-related differences in resource use, it is assumed that there is reduced interspecific competition for prey between larger L. limanda and P. platessa and both non-commercial flatfishes, probably facilitating resource partitioning within the same area. In contrast, smaller L. limanda and P. platessa may compete directly for the same prey resources with B. luteum and A. laterna. Furthermore, prey availability of most important prey items of the studied flatfishes was relatively low in the study area. Therefore, increasing abundances of B. luteum and A. laterna in the southern North Sea since the late 1980s, owing to fishing effects and climate change, might affect the population dynamics of L. limanda and P. platessa.
在德国北海（北海南部）的一个研究区域中，比较了两种非商业比目鱼（扁鱼 Buglossidium luteum 和舌鳎 Arnoglossus laterna）和两种商业比目鱼（牙鳕 Limanda limanda 和欧鲽 Pleuronectes platessa）的饮食，以研究这些物种之间的猎物资源分配。A. laterna 和 B. luteum 的饮食主要包括甲壳类动物（桡足类、端足类、糠虾和十足目动物），而 L. limanda 和 P. platessa 的饮食主要由多毛类动物组成。根据这些比目鱼的不同鱼类大小类别的肖纳指数计算，小尺寸的 L. limanda 和 P. platessa 与 B. luteum 和 A. laterna 之间存在生物学上显著的饮食重叠，它们使用类似的较小猎物（如端足类、桡足类和幼年双壳类动物）的猎物资源。相比之下，随着体型的增加，L. limanda 和 P. platessa 的饮食会向较大的猎物（如多毛类动物和十足目动物）转变，导致与 B. luteum 和 A. laterna 的饮食重叠值较低。由于资源利用方面的这些大小相关差异，人们认为较大的 L. limanda 和 P. platessa 与两种非商业比目鱼之间的猎物竞争会减少，这可能有助于在同一区域内实现资源分配。相比之下，较小的 L. limanda 和 P. platessa 可能会与 B. luteum 和 A. laterna 直接竞争相同的猎物资源。此外，在所研究的比目鱼的最重要猎物中，大多数猎物的可利用性在研究区域相对较低。因此，自 20 世纪 80 年代末以来，由于捕捞效应和气候变化，B. luteum 和 A. laterna 在北海南部的数量增加，可能会影响 L. limanda 和 P. platessa 的种群动态。
