Collaborative Research: The Role of Larval Orientation Behavior in Determining Population Connectivity

了解幼鱼离开父母的距离是海洋生态学的一个主要目标，因为这种分散可以在不同的种群之间建立联系，从而影响种群的大小和动态。反过来，了解种群动态的驱动因素对于有效的渔业管理至关重要。海洋生态学家使用了两种不同的方法来了解鱼类种群是如何联系在一起的：测量连通性的遗传方法和预测连通性的海洋学模型。然而，在海洋学模型的预测和遗传方法的观测之间存在着不匹配。人们认为这种不匹配是由幼鱼或幼鱼的行为引起的。本研究的目的是研究野生幼鱼在整个发育过程和各种环境条件下的定向能力，以了解种群连通性的观察和预测之间的差距是否可以解决。该项目将在三个关键领域产生更广泛的影响：通过培养多层次的青年科学家来整合研究和教学；扩大来自代表性不足群体的本科生的参与；以及通过建立一个以英语和西班牙语提供信息和资源的网站，广泛传播结果。本研究的总体目标是研究幼虫定向行为在整个个体发育过程中决定种群连通性的作用。这将使用霓虹虾虎鱼（Elacatinus lori）作为伯利兹的模型系统来完成。研究系统的选择是基于这样一个事实，即直接遗传方法已经被用来描述该物种的完整扩散核心，这些观察表明，该物种的扩散范围不如高分辨率生物物理模型预测的那么广泛；从孵化到定居都可以在实验室中饲养，为拟议的实验提供了所有年龄的幼虫的可靠来源；一个新的，经过验证的行为观察平台，漂流原位室（DISC），可以测量开放水域中幼虫的定向行为。该项目有三个具体目标：通过将幼虫定向行为与发育感觉解剖相关联来了解幼虫定向能力的个体发生变化；通过个体发生分析不同环境条件下幼虫定向精度的变化；为了测试幼虫定向行为的其他假设，也就是说，确定幼虫在发育过程中朝向哪里。

Understanding how far young fish move away from their parents is a major goal of marine ecology because this dispersal can make connections between distinct populations and thus influence population size and dynamics. Understanding the drivers of population dynamics is, in turn, essential for effective fisheries management. Marine ecologists have used two different approaches to understand how fish populations are connected: genetic methods that measure connectivity and oceanographic models that predict connectivity. There is, however, a mismatch between the predictions of oceanographic models and the observations of genetic methods. It is thought that this mismatch is caused by the behavior of the young, or larval, fish. The objective of this research is to study the orientation capabilities of larval fish in the wild throughout development and under a variety of environmental conditions to see if the gap between observations and predictions of population connectivity can be resolved. The project will have broader impacts in three key areas: integration of research and teaching by training young scientists at multiple levels; broadening participation of undergraduates from underrepresented groups; and wide dissemination of results through development of a website with information and resources in English and Spanish.The overall objective of the research is to investigate the role of larval orientation behavior throughout ontogeny in determining population connectivity. This will be done using the neon goby, Elacatinus lori, as a model system in Belize. The choice of study system is motivated by the fact that direct genetic methods have already been used to describe the complete dispersal kernel for this species, and these observations indicate that dispersal is less extensive than predicted by a high-resolution biophysical model; E. lori can be reared in the lab from hatching to settlement providing a reliable source of larvae of all ages for proposed experiments; and a new, proven behavioral observation platform, the Drifting In Situ Chamber (DISC), allows measurements of larval orientation behavior in open water. The project has three specific objectives: to understand ontogenetic changes in larval orientation capabilities by correlating larval orientation behavior with developmental sensory anatomy; to analyze variation in the precision of larval orientation in different environmental contexts through ontogeny; and to test alternative hypotheses for the goal of larval orientation behavior, i.e., to determine where larvae are heading as they develop.