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

关于决定栖息在岩礁和珊瑚礁上的生物种群数量的主要过程，存在着相当大的争论。这些生物中的大多数都有复杂的生命周期，包括广泛分散的繁殖体和相对久坐的幼体和成体，因此在特定珊瑚礁的‘出生率’等于繁殖体的定居速率。争论的焦点是繁殖物的供应与定居后过程在多大程度上决定了当地人口的规模和动态。为了解决这一问题，我们必须知道决定特定地点人口规模的人口比率(定居点、移民、死亡率和迁出)是否以及如何随人口密度而变化(即，这些比率的变化是否依赖于密度)。回答这个问题不仅仅是学术上的兴趣，因为首先，它为理解当地种群数量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是必不可少的，其次，对于任何生物来说，这个问题很少得到充分的回答。这项合作研究旨在回答是什么推动了四种海洋鱼类以全面的方式在两个非常不同的环境中生活的问题：温带和热带珊瑚礁。这种多鱼种、多系统的办法将提供一些共性，或许可以适用于其他海洋系统，包括底层和底层渔业。利用行之有效的方法，这项研究的实验和观察相结合的设计将研究幼虫供应、定居、招募、迁入、迁出、竞争，特别是捕食及其机制在推动当地种群动态方面的作用。实地工作的结果将纳入人口动态的数学模型，以提供适用于其他类似组织的系统的概念性。

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 systems.