Project Summary

David Mountain, Dave Townsend, Jack Green, and Peter Berrien

U.S. GLOBEC: Broad-Scale Ichthyoplankton, Hydrography and Nutrient Studies on Georges Bank

This proposal represents a continuation of the broad-scale survey to 1999, the final field year of the program, and addresses three components of the survey: hydrography, nutrients and chlorophyll, and the larval fish populations; as well as the continued analysis of the data collected on the broad-scale survey in 1995 - 1998. The hydrographic data will document the evolution of water column conditions during the larval life stages, and provide an index of interannual variability in the environmental conditions over the life of the program. The nutrient and chlorophyll studies will provide data to test ideas about the overall limiting effect that nitrogen exerts on the higher trophic level productivity on Georges Bank. The larval sampling will measure the distribution and abundance of eggs and larvae of cod and haddock, from which estimates of production and mortality rates will be made for these populations. The spatial and temporal distribution of the mortality rates will be compared to the distributions of predators, prey and physical forcing to determine trophic and environmental factors associated with mortality.