The ecology of focal forage fish species and its impact on marine predators

海豚是一种类似小鲤鱼的小鱼，是捕食许多无脊椎动物的重点饲料鱼物种，反过来也是大多数大型捕食者的猎物，包括西北大西洋的鳕鱼、海豹、鲸鱼和鸟类。Capelin为营养水平之间的能量转移提供了必要的联系，因此，通常被认为是调节生态系统水平的变化。我最近在纽芬兰沿海的深水(海底)发现了海豚产卵，这种物种主要在海滩上产卵。在这些产卵地点大量聚集的海豚，使捕食者集中在一起。这导致生物体聚集在高丰度的地区，通常被称为“生物热点”。我的研究重点是Capelin与它们的物理环境和这些热点中的其他物种的相互作用。具体地说，我研究了海豚是否根据目前的环境条件在海滩和海底产卵栖息地之间进行选择，或者海豚是否已经进化成不同的专属海滩和海底产卵者种群。此外，我还研究了在热点地区觅食如何影响海豚捕食者的生物学。为了做到这一点，我在船上使用了一种先进的海洋电子设备的新型组装。我将这些措施与基于实验室的水箱实验、遗传分析、耳石微结构和稳定同位素技术以及捕食者觅食策略结合起来。我的研究涉及大学科学家和商业渔民之间的合作努力，这已经并将继续在我们对鱼类生态和食物网络动态的理解方面取得重大进展。最终，这项研究将提高Capelin种群评估指数的准确性，并促进新颖、精辟的渔业管理方法，以避免在我们的沿海水域和全球社区发生的生态和社会经济灾难。

Capelin, a small minnow-like fish, is the focal forage fish species that preys on many invertebrates and is in turn preyed on by most large predators, including cod, seals, whales and birds in the Northwest Atlantic. Capelin provide essential linkages for energy transfer among trophic levels and, thus, are often thought to mediate ecosystem-level changes. I recently discovered capelin spawning in deep water (demersal) in coastal Newfoundland, where this species is primarily thought to spawn on beaches. Large aggregations of capelin form at these spawning sites, causing predators to concentrate. This results in areas where high abundances of organisms gather, often referred to as 'biological hotspots'. My research focuses on the interaction of capelin with their physical environment and other species within these hotspots. Specifically, I examine whether capelin select between beach and demersal spawning habitat on the basis of current environmental conditions or whether capelin have evolved into different populations of obligate beach and demersal spawners. Additionally, I examine how foraging within hotspots influences the biology of capelin predators. To do this, I employ a novel assemblage of sophisticated marine electronic equipment aboard ships. I combine these measures with laboratory-based tank experiments, genetic analyses, otolith microstructure and stable isotope techniques, along with predator foraging strategies. My research involves collaborative efforts between university scientists and commercial fishers, which has and will continue to make major advancements in our understanding of fish ecology and food web dynamics. Ultimately, this research will increase the accuracy of capelin stock assessment indices and promote novel, incisive fisheries management approaches to avoid ecological and socioeconomic catastrophes that have occurred in our coastal waters and communities around the globe.