Bioenergetics Modeling of San Francisco Estuary Striped Bass and the Development of Individual Based Models for Striped Bass and Longfin Smelt in the San Francisco Estuary

A bioenergetics model and an individual-based life cycle model were developed to quantify long-term consumption patterns and investigate the population dynamics, respectively, of striped bass (Morone saxatilis ) in the San Francisco Estuary (SFE). Additionally, an individual-based life cycle model to investigate the population dynamics of longfin smelt ( Spirinchus thaleichthys) in the San Francisco Estuary (SFE) was developed. Declines in the pelagic fish community (including striped bass and longfin smelt) in the SFE over the past several decades have created a significant resource management issue in California. The striped bass bioenergetics model quantifies their consumption demands on their prey, an important key to improving the understanding on long-term trends of fish in the SFE. The individual-based models (i.e., striped bass and longfin smelt) include movement for all life stages (i.e., eggs through adults), growth via a bioenergetics model, and spatially explicit dynamics, including mortality and fecundity. The striped bass individual-based model was applied under seven different scenarios from 1990 through 2004 to examine the parts of the life cycle that strongly affect abundance trends. Similarly, the longfin smelt individual-based model was applied under a single scenario from 1990 through 2005 to identify life stages that affect population-level abundance trends. Further details of these models, modeling approaches, and model results are discussed in detail in the subsequent chapters; abstracts specific to each chapter are provided at the beginning of each chapter.