• What are the salient differences in recruitment patterns and their causal mechanisms in 



high- and low-latitude systems? 



• Under what conditions is recruitment and subsequent ecosystem structure more likely to 



be physically (transport, temperature, etc.) or biologically (starvation, predation, etc.) 

 mediated? 



• How is recruitment related to nutrient availability and primary production? How Is 



variability at the primary producer level expressed in production and ecosystem 

 dynamics at higher trophic levels? 



Major aspects include: 



• Developing a broader understanding of the annual and seasonal variability and 



productivity of ecosystems and the effect of ocean climate on such variability; 



• Expanding collaborative research by physicists and biologists at a variety of scales to 



learn how larvae, their predators, and their prey are aggregated and dispersed; 



• Use of new sampling, identification, and data analysis methods to bring the plankton 



studies into the same time frame as important physical processes; 



• Determining the kinds and abundances of predators and their rates of predation on 



planktonic or young stages of nekton; 



• Application of emerging technologies, including in situ sampling from research vessels, 



mesocosm studies on larvae-zooplankton interactions (feeding, predation), acoustic 

 methods to estimate abundance of larvae and zooplankton, and satellite methods for 

 assessing primary production and its variability; 



• Developing and applying numerical models to guide experimental research and predict how 



physical processes and nutrient availability influence recruitment potential; and 



• Developing coherent theory regarding evolution of adaptive strategies by marine 



organisms which enhance the long-term survival of their populations. 



Incremental support growth averaging about $3M annually for FY 1988-93 should provide the 

 basic underpinnings for our understanding of plankton dynamics, larval ecology, and predation 

 as they collectively influence recruitment variability and higher trophic level productivity. 

 This growth will also allow development and experimental use of new technologies and 

 methodologies. Major, long term field experiments based on this developmental work will be 

 conducted in the mid-to-late 1990's and cost $20-25M annually. Ship and facility costs are 

 included. 



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