Anthropogenic perturbations and climate change have altered the zooplankton community structure in the Klang Strait during the past 30 years, in that the taxa of large-bodied crustaceans (Acartiidae, Calanidae, Pseudodiaptomidae) are being replaced by those of small-bodied crustaceans (Oithonidae, Ectinosomatidae), gelatinous jellyfish, and appendicularians. Since zooplankton constitutes the main larval food, we questioned: have bottom-up effects impacted larval fish feeding via the food chain? Larval fish that were sampled previously (1985–1986) and nearly three decades thereafter (2013–2014) were analysed for their dietary composition. Despite the dramatic replacements of zooplankton taxa due to escalating anthropogenic disturbances, the dominant copepod families, Paracalanidae, Oithonidae and Euterpinidae, remain the major prey for fish larvae. Dietary shifts in prey composition from before to after impact depend on the larval fish family and their ontogenetic stage. Dietary changes are observed in the Bregmacerotidae, Engraulidae, Gobiidae and Sciaenidae that opportunistically feed on the small-bodied copepods (oithonids and Parvocalanus crassirostris), whereas the Callionymidae, Clupeidae and Cynoglossidae naturally feed on these copepods even before these prey become numerically dominant with anthropogenic disturbance. There is no dietary shift in the Leiognathidae, exceptional in that they are specialists feeding mainly on detritus and polychaete larvae. Since the bottom-up effects are not comprehensive among fish families and dietary plasticity is evident, it is postulated that only the intolerant or non-adaptable larval species are adversely affected by the environmental perturbations.

在过去的 30 年里，人为扰动和气候变化改变了巴生海峡的浮游动物群落结构，大型甲壳类（Acartiidae、Calanidae、Pseudodiaptomidae）的分类群正在被小型甲壳类（Oithonidae、 Ectinosomatidae)、凝胶状水母和附肢动物。由于浮游动物是幼鱼的主要食物，我们质疑：自下而上的影响是否影响了幼鱼通过食物链进食？对之前（1985-1986 年）和此后近三年（2013-2014 年）采样的幼鱼进行了膳食成分分析。尽管由于不断升级的人为干扰，浮游动物类群发生了戏剧性的变化，但占优势的桡足类家族 Paracalanidae、Oithonidae 和 Euterpinidae 仍然是鱼类幼虫的主要猎物。从影响之前到之后猎物组成的饮食变化取决于幼鱼家族及其个体发育阶段。在 Bregmacerotidae、Engraulidae、Gobiidae 和 Sciaenidae 中观察到饮食变化，它们机会性地以小型桡足类（oithonids 和Parvocalanus crassirostris )，而 Callionymidae、Clupeidae 和 Cynoglossidae 甚至在这些猎物因人为干扰而在数量上占主导地位之前就自然地以这些桡足类动物为食。Leiognathidae 的饮食没有变化，特殊之处在于它们是主要以碎屑和多毛类幼虫为食的专家。由于自下而上的影响在鱼类家族中并不全面，而且饮食可塑性很明显，因此推测只有不耐受或不适应的幼虫物种会受到环境扰动的不利影响。