Local Population Dynamics of Temperate and Tropical Reef Fishes at Multiple Scales

9617483希克森 关于决定栖息在岩石和珊瑚礁上的生物种群规模的主要过程，存在着相当大的争论。大多数这些生物有复杂的生命周期，包括广泛分散的繁殖体和相对定居的幼鱼和成年鱼，因此在某一特定珊瑚礁的“出生率”相当于繁殖体的定居率。争论的焦点是繁殖体的供应与定居后的过程在多大程度上决定了当地的人口规模和动态。为了解决这个问题，我们必须知道，决定特定地点人口规模的人口统计率（定居点，移民，死亡率和移民）是否以及如何随着人口密度而变化（即，这些速率的变化依赖于密度）。 探讨这个问题不仅仅是学术上的兴趣，因为，首先，它为理解当地种群规模是如何自然调节的提供了基础，这对于有效管理渔业和其他自然种群至关重要，其次，它很少被任何生物体充分回答。 这项合作研究的目的是回答什么驱动当地种群动态的问题，以全面的方式为四种海洋鱼类栖息在两个非常不同的环境：温带和热带珊瑚礁。这种多鱼种、多系统的办法具有一定的普遍性，或许可以适用于其他海洋系统，包括底层捕捞和底鱼捕捞。使用行之有效的方法，本研究的实验和观察相结合的设计将研究幼虫供应，定居，招聘，移民，移民，竞争，特别是捕食及其机制，在驱动当地人口动态的作用。实地工作的结果将被纳入人口动态的数学模型，以提供适用于其他类似组织系统的概念性的一般性。

9617483 Hixon There is considerable debate regarding the major processes that determine population sizes of organisms inhabiting rocky and coral reefs. Most of these organisms have complex life cycles that include widely dispersive propagules and relatively sedentary juveniles and adults, such that the "birth rate" at a particular reef is equivalent to the rate of settlement of propagules. The controversy focuses on the extent to which supply of propagules vs. post-settlement processes determine local population size and dynamics. To resolve this issue we must know whether, and how, the demographic rates that determine population size at a particular site (settlement, immigration, mortality, and emigration) change with population density (i.e., are the changes in these rates density-dependent). Answering this question is of more than academic interest because, first, it provides the basis for understanding how local population size is regulated naturally, which is essential for effective management of fisheries and other natural populations, and second, it has seldom been answered adequately for any organism. This collaborative research is designed to answer the question of what drives local population dynamics in a comprehensive manner for four species of marine fish inhabiting two very different environments: temperate and tropical reefs. This multi-species, multi-system approach will provide some generality which can perhaps be applied to other marine systems, including demersal and bottom fisheries. Using well-proven methods, the combined experimental and observational design of this study will examine the roles of larval supply, settlement, recruitment, immigration, emigration, competition, and especially predation and its mechanisms, in driving local population dynamics. Results of the field work will be incorporated into mathematical models of population dynamics to provide conceptual generality applicable to other similarly organized system s.