Trophic dynamics, growth and survival of juvenile salmon in coastal lake and marine ecosystems

太平洋鲑鱼是加拿大和环太平洋国家的重要渔业资源，与区域和国家经济以及沿海社区和第一民族的社会和文化遗产有着重要联系。近几十年来，太平洋鲑鱼的产量一直在下降，一些种群几乎消失。虽然潜在的机制尚不清楚，但人们越来越意识到，这种下降可能与沿海海洋和淡水生态系统中温度、营养物质、浮游动物、饲料鱼和捕食者组合的数量和质量的变化有关。目前，对成年鲑鱼年收益的预测和预报存在很大的不确定性，这可能导致重大的商业损失，并对沿海社区造成负面的社会经济后果。我建议在不列颠哥伦比亚省沿海太平洋生态系统的尺度上理解和模拟鲑鱼幼鱼的摄食、食物网和资源生态的大尺度变化。这对于提高加拿大更有信心地预测和预测太平洋鲑鱼的生长、生存和相关的成年鲑鱼回报的能力至关重要。我还建议确定在10-12个红鱼湖中决定红鱼鱼种大小和年龄分布的主要过程，并测试其他同居的浮游动物（如棘鱼和Mysis）如何通过红鱼鱼种改变食物网和资源分配。我们假设，通过猎物质量和数量的变化，变化的湖泊或海洋条件可能会影响食物网动态、营养相互作用和物种内部和物种之间的饮食重叠作为大小的函数，并最终导致太平洋鲑鱼幼鱼的生长和生存变化。这项研究计划有望对太平洋鲑鱼幼鱼的食物网动态和营养相互作用产生新的见解和更好的理解，这将为加拿大宝贵的自然资源之一带来更好的管理策略。

Pacific salmon are an important fisheries resource for Canada and the Pacific rim countries, with significant links to both regional and national economies, and social and cultural heritage of costal communities and First Nations. In recent decades the productivity of Pacific salmon has been declining, with several stocks all but disappearing. Although the underlying mechanisms are still unclear, there is a growing sense that such declines may be linked to the variability in temperature, nutrients, the quantity and quality of zooplankton, forage fish and predator assemblages in coastal marine and freshwater ecosystems. Currently there are significant uncertainties in the prediction and forecast of annual adult salmon returns, which can lead to significant loss of business and negative socio-economic consequences for coastal communities. I propose to understand and model the large-scale variability in feeding, foodweb and resource ecology of juvenile salmon at the scale of coastal Pacific ecosystems of BC. It is critical to improving Canada's ability to forecast and predict the growth, survival and associated adult returns of Pacific salmon with greater confidence. I also propose to identify the major processes that determine size- and age-distribution of sockeye fry in 10-12 sockeye lakes, and test how other cohabiting zooplanktivores (e.g. stickleback and Mysis) alter foodwebs and resource partitioning by sockeye fry. We hypothesized that variable lake or ocean conditions through shifts in the quality and quantity of prey may affect foodweb dynamics, trophic interactions and diet overlaps within and among species as a function of size, and eventually leading to variable growth and survival of juvenile Pacific salmon. This research program is expected to produce new insights and better understanding of foodweb dynamics and trophic interactions of juvenile Pacific salmon, which will lead to better management strategies for one of Canada's precious natural resources.