9632634 GIFFORD The specific focus of this project will be to describe quantitatively the contribution of nano- and microplankton (i.e., plants and animala, 2-200 um in size) prey fields to recruitment of target copepod populations on Georges Bank. The PIs hypothesize that early stage copepods advected onto the Bank from the Gulf of Maine and the Great South Channel experience an enriched food environment on-Bank relative to source regions. The project will examine consumption of nano- and microplankton by naupliar stages N3-N6 of the calanoid copepods Calanus finmarchicus and Pseudocalanus spp. in: 1) source areas in the Great South Channel and the Gulf of Maine where the advective regime contributes water (and presumably copepods) to Georges Bank; 2) on-Bank regions receiving these inputs, including the region of enhanced production on the Northeast Peak; and 3) areas on either side of the tidal front separating the Bank crest from deeper waters on the Southern Flank. The study focuses on Calanus and Pseudocalanus because these species dominate the zooplankton biomass of Georges Bank during the January-June period. Naupliar stages will be studied because these are the stages at which copepods recruit to the population. Field sampling will be conducted in the Great South Channel and southern Gulf of Maine because these are sites for advective inputs of water and zooplankton onto the Bank crest. This project is a part of the U.S. GLOBEC Northwest Atlantic Field Studies, Phase 2 program. ***