Human and climate forcing of zooplankton populations Introduction

Zooplankton play a key role in the pelagic foodweb by controlling phytoplankton production and shaping pelagic ecosystems. In addition, because of their critical role as a food source for larval and juvenile fish, the dynamics of zooplankton populations have a significant influence on recruitment to fish stocks. In 1961, ICES convened the First Zooplankton Production Symposium in Charlottenlund, Denmark. ICES also played a leading role in the Second Zooplankton Production Symposium on “Zooplankton Production: measurement and role in global ecosystem dynamics and biogeochemical cycles”, held in Plymouth, UK, in 1994. The increasing importance of international programmes such as GLOBEC, the general concerns about global change, and the changing role of zooplankton in ocean ecosystems were reflected in the development of this Symposium. This trend was developed further in the Third Zooplankton Production Symposium on “The role of zooplankton in global ecosystem dynamics: comparative studies from the world oceans”, held in Gijon, Spain, in 2003. It was the first time that the Symposium was co-sponsored by ICES, PICES, and GLOBEC. The Fourth International Zooplankton Production Symposium was held in Hiroshima, Japan, from 28 May to 1 June 2007. This Symposium, co-sponsored by ICES, PICES, and GLOBEC, was the first of the series to be held outside Europe, and its focus was on “Human and climate forcing of zooplankton populations”. This symposium not only provided a better knowledge of zooplankton production processes but also contributed to a deeper understanding of all marine ecosystems. Zooplanktologists from countries around the world met to address issues important to marine science and to society in this time of rapid and serious climate change. The week-long symposium involved 334 participants from 46 countries, who contributed 141 oral and 250 poster presentations. These demographics clearly indicated the international nature of zooplankton research. The opening plenary session provided three excellent presentations on different aspects of the symposium theme: