Collaborative Research: Open-Water Plantivores and Turbidity: Influence on Size-Structured Interactions among Centrarchid Fishes

美国东南部和中部的大多数湖泊和水库与中西部的上西部湖泊不同，因为它们的水非常浑浊，而且存在主要以浮游动物为食的开阔水域鱼类(例如，肌鱼和金枪鱼)。这两个因素对湖泊中无脊椎动物和鱼类的生产有深远的影响。这项研究将研究沙鱼的存在如何影响鱼类物种的相互作用，以及沙鱼对湖泊系统的其他方面(例如藻类和浮游动物)的影响。它试图将从北部鱼类群落研究中获得的实质性了解推广到该国更广泛的地理区域。由于鱼类在生长过程中的饮食和栖息地用途的变化，物种间的相互作用往往是复杂的(例如，许多大型捕食性鱼类以小型浮游动物为食开始其生活)，因此，只有考虑到每个因素如何影响鱼类生活史的各个点，才能理解鱼体和浑浊的影响。该项目将利用一系列实验室、池塘和全湖实验，旨在研究沙鱼对三种重要运动性鱼类：蓝鳍金枪鱼、大口黑鱼和白蟹鱼的幼体、幼体和成体的影响。这项工作利用了一个独特的机会来研究俄亥俄州两个水库中的鱼、浮游动物和浮游植物，在全湖引入丝鳍鱼之前和之后。这项研究将提供急需的洞察，以了解引入的浮游动物对当地鱼类动物的影响，以及它们在湖泊管理中的潜在作用。俄亥俄州自然资源部正在资助对研究水库的额外研究，这将增加正在产生的全部信息库的概括性和深度。

Most lakes and reservoirs of the southeastern and central United States differ from upper-midwestern lakes by having very turbid water and the presence of open-water fish species which feed predominantly on zooplankton (e.g., gizzard and threadfin shad). These two factors have profound effects on the production of invertebrates and fishes in lakes. This study will examine how the presence of shad affects fish species interactions, as well as studying the impact of shad on other aspects of the lake system (e.g., algae and zooplankton). It seeks to extend the substantial understanding gained from studies of northern fish communities to a geographically broader portion of the country. Because species interactions in fishes are often complex due to changes in their diet and habitat use as they grow, (e.g., many large predatory fish begin their lives feeding on small zooplankton), the impact of shad and turbidity can only be understood by considering how each factor influences all points in a fish's life history. The project will utilize a series of laboratory, pond, and whole-lake experiments designed to examine the effect of shad on the larvae, juveniles and adults of three important sport fishes; bluegill, largemouth bass, and white crappie. This work capitalizes on a unique opportunity to study fish, zooplankton and phytoplankton in two Ohio reservoirs before and after the whole-lake introduction of threadfin shad. The study will provide much needed insight into the effects of introduced planktivores on the resident fish fauna and their potential role in lake management. Ohio Department of Natural Resources is funding additional research on the study reservoirs which will add generality and depth to the total information base being generated.