Ecology of Pacific Salmon: Introduction
Christian E. Zimmerman and Charles C. Krueger
A key component of the program goal of the Arctic-Yukon-Kuskokwim Sustainable Salmon Initiative (AYK SSI) is to “..understand the trends and causes of variation in abundance and fisheries…” of Pacific salmon(AYK SSI 2006). To achieve this goal, information concerning population biology, freshwater ecology, marine ecology, and population dynamics is needed to understand the variables controlling population abundance and trends. The papers in this section were selected to address these topics and divided into two broad habitat-based themes: freshwater and marine.
The freshwater ecology theme contains papers that examine habitat, food supply, and energetics of juvenile salmon in streams and rivers, population genetics, conservation of genetic diversity, and the role of environmental variation in controlling salmon productivity. Freshwater ecology and the role of habitat in controlling salmon populations in the AYK region have received little attention in the past by researchers (AYK SSI 2006). A primary goal for this section was to begin to remedy this significant knowledge gap. In organizing this section, we invited papers from those who have worked on these topics both in the region and from elsewhere. Bradford et al. (2009, this volume) discusses the production of juvenile Chinook salmon Oncorhynchus tshawytscha in the upper Yukon River relative to habitat. Wipfli (2009, this volume) then discusses the role of food supply in controlling growth and productivity of juvenile salmonids in streams and the connection to nutrients imported by adult salmon migrating from marine waters. Beauchamp (2009, this volume) links food supply, temperature mediated metabolism, and food capture ability to examine growth potential using bioenergetic modeling. Then, Nemeth et al. (2009, this volume) focuses on the role of habitat in controlling the freshwater productivity of salmon with an examination of habitat/salmon productivity relations in two Norton Sound rivers.