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茎柔鱼(Dosidicus gigas)是大洋性重要经济头足类之一,在食物链中起着重要作用。通过对2009年9-10月秘鲁外海采集的383尾茎柔鱼胃含物进行分析与研究,以了解调查期间茎柔鱼摄食习性的时空变化特性。研究认为,摄食等级在9-10月份间存在极显著差异(P<0.01),其摄食等级9月平均值高于10月。雌雄个体间和昼夜间摄食等级差异不显著(P>0.05)。但昼夜消化水平差异极显著(P<0.01),当地时间19:00时(以下类同)为最低,平均为1级,03:00时达到最高,为6级。捕食主要发生在19:00时至21:00时。个体中基本不存在连续性摄食的现象。空胃现象仅在胴长为25～50 cm的个体中发现;20～25 cm胴长组中未发现鱼类,25～60 cm各胴长组中鱼类的比例均最高,胴长大于50 cm的胃含物仅为鱼类;同类残食主要在25～35 cm、40～45 cm胴长组中发生;甲壳类仅在25～40 cm胴长组中发现,但食性选择差异不显著(P>0.05)。
Dosidicus gigas is one of the most economically important cephalopods in the oceans and plays an important role in the food chain. The stomach contents of 383 squidfish collected from the Peruvian off-shore in September-October 2009 were analyzed and studied in order to understand the spatiotemporal variation of feeding habits of Scurry fish during the survey period. The study concluded that there was a significant difference in the level of food intake between September and October (P <0.01), and the average level of ingestion in September was higher than that in October. There was no significant difference in the feeding level between male and female individuals and between day and night (P> 0.05). However, diurnal digestibility levels were significantly different (P <0.01). At 19:00 local time (the same below) were the lowest, with an average of 1 grade, reaching the highest level at 03:00 and being 6 grades. Predation occurs mainly between 19:00 and 21:00. There is basically no continuous feeding in the individual. The phenomenon of empty stomach was found only in individuals with a body length of 25 ~ 50 cm. No fish was found in the 20-25 cm body length group, and the proportion of fish in the groups of 25-60 cm body length was the highest cm was only for fish. The same diet mainly occurred in 25-35 cm and 40-45 cm long-body carcasses. Crustaceans were only found in 25-40 cm long-body carcass group, but there was no significant difference in diet selection (P> 0.05).