Rojas-Herrera Agustin A, Mascaró Maite, Chiappa-Carrara Xavier
Escuela Superior de Ecologia Marina, Universidad Aut6noma de Guerrero. Apdo. Postal 1606, 39390 Acapulco, México.
Rev Biol Trop. 2004 Dec;52(4):959-71.
Diet composition of the Pacific snapper (Lutjanus peru) 130-684 mm fork length (FL) and the spotted snapper (Lugjanus guttatus) 120-550 mm FL, was analyzed. Monthly samples were obtained from commercial landings in three regions off the coast of Guerrero, Mexico. Percentage by number (%N), percentage by weight (%W), and percentage of occurrence (%O) were calculated for each prey and summarized as the index of relative importance. Both species are polyphagous predators feeding on a variety of prey: Sixty-eight prey items, mainly fish (%W = 50.9), crustaceans (%W = 35.6), and mollusks (%W = 7.2), were found in the stomach contents of L. peru, while 88 components were identified in the diet of L. guttatus, the most important prey being fish (%W = 50.8) and crustaceans (%W = 43.4). Diet overlap between species is not significant (p<0.05), indicating that competition for food is unlikely. Based on published values of the relative importance index, the diets of these Lutjanidae were analyzed considering different regions of the Pacific coast of Mexico and Costa Rica, and similarities among sites and species were discussed. The cluster analysis showed that similarities among species inhabiting in the same area are more important than within organisms of the same species living in different zones. Results suggest that prey availability rather than food selectivity, conditions the feeding behavior of these fish species.
对叉长130 - 684毫米的秘鲁笛鲷（Lutjanus peru）和叉长120 - 550毫米的斑点笛鲷（Lugjanus guttatus）的饮食组成进行了分析。每月从墨西哥格雷罗海岸外三个地区的商业渔获中采集样本。计算了每种猎物的数量百分比（%N）、重量百分比（%W）和出现百分比（%O），并将其总结为相对重要性指数。这两个物种都是以多种猎物为食的多食性捕食者：在秘鲁笛鲷的胃内容物中发现了68种猎物，主要是鱼类（%W = 50.9）、甲壳类动物（%W = 35.6）和软体动物（%W = 7.2），而在斑点笛鲷的饮食中鉴定出88种成分，最重要的猎物是鱼类（%W = 50.8）和甲壳类动物（%W = 43.4）。物种间的饮食重叠不显著（p<0.05），这表明食物竞争不太可能发生。根据相对重要性指数的已发表值，分析了这些笛鲷科鱼类在墨西哥和哥斯达黎加太平洋海岸不同地区的饮食情况，并讨论了不同地点和物种之间的相似性。聚类分析表明，同一地区栖息的物种之间的相似性比生活在不同区域的同一物种个体之间的相似性更为重要。结果表明猎物的可获得性而非食物选择性决定了这些鱼类的摄食行为。
