Department of Marine Ecology, University of Gothenburg, Kristineberg 566, 45178 Fiskebäckskil, Sweden.
J Fish Biol. 2012 Jun;80(7):2528-48. doi: 10.1111/j.1095-8649.2012.03306.x.
The feeding ecology of two common indigenous (Sphyraena viridensis and Sphyraena sphyraena) and one abundant non-indigenous sphyraenid species, Sphyraena chrysotaenia, of Indo-Pacific Ocean origin, was investigated in an area of the eastern Mediterranean Sea. The stomach contents of 738 individuals of varying size, collected during the period December 2008 to August 2009, were examined. The dietary analyses revealed that all three species were specialized piscivores with a diet consisting of >90% fish, both by number and mass. Concurrent sampling of the fish assemblage made it possible to calculate selectivity as well as diet breadth and overlap of these strict piscivores. Even though several prey species were found in the stomachs of the three predators examined, selectivity towards Atherina boyeri was highly significant. For all species examined, >70% of the diet by mass was made up by three indigenous species of commercial value: Spicara smaris, Boops boops and A. boyeri. Diet breadth and size of prey increased with increasing body size for all predators. With increased body size, the diet overlap between indigenous and non-indigenous species decreased. This could be attributed to increased diet breadth and the specific life-history characteristics of indigenous species developing into larger individuals. During winter, the condition factor of the non-indigenous species was significantly lower than that of the indigenous, indicating that winter conditions in the Mediterranean Sea may limit its further expansion north and westward. With this study, the gap in knowledge of the feeding preferences of the most abundant piscivorous species found in coastal areas of the study region is filled. Additionally, the results indicate that non-indigenous species familial affiliation to indigenous ones does not facilitate invasion success.
本研究调查了东地中海地区两种常见的本地（绿鳍马面鲀和马面鲀）和一种丰富的外来的脂眼鲱科鱼类（黄鳍马面鲀）的摄食生态。在 2008 年 12 月至 2009 年 8 月期间收集了不同大小的 738 个个体的胃内容物进行检查。饮食分析表明，所有三种鱼类均为专门的肉食性鱼类，其饮食中鱼类占比>90%，无论是按数量还是质量计算。同时采集鱼类群集样本，使得这些严格的肉食性鱼类的选择性、饮食广度和重叠度都可以被计算。尽管在三种受检捕食者的胃中发现了几种猎物物种，但对 Atherina boyeri 的选择性具有高度显著性。对于所有受检物种，超过 70%的饮食由三种具有商业价值的本地物种组成：绿鳍马面鲀、拟鲹和 A. boyeri。所有捕食者的饮食广度和猎物大小均随身体大小的增加而增加。随着体型的增大，本地和外来物种之间的饮食重叠度降低。这可能归因于饮食广度的增加和本地物种特定的生活史特征使其个体更大。在冬季，外来物种的条件因子显著低于本地物种，这表明地中海冬季的条件可能限制了其在北部和西部的进一步扩张。通过本研究，填补了研究区域沿海地区最丰富的肉食性鱼类摄食偏好知识的空白。此外，研究结果表明，非本地物种与本地物种的亲缘关系并不会促进入侵的成功。
