It was also felt that current models of secondary production are complex and that this complexity obscures the understanding that could be gained from the models. Several respondents recommended that secondary production models be reduced to basic elements to give simple models with few parameters. An issue that arose was how simple do the models need to be to address questions about the basic processes that underlie secondary production.
Several comments were made about processes not presently (or inadequately) included in existing secondary production models. These include: descriptions of the predator and prey fields, realistic predation mortality, the effects of prey spectrum on prey-specific removal, and treatment of spatial heterogeneity in the predator and prey fields. One respondent pointed out that existing secondary production models have not undergone rigorous testing to determine how well they work and evaluate their more general use. For this to happen, modeling approaches need to be available to the community so that observations can be more readily input to models. Also, several respondents indicated the need for models that can include fast and slow processes (e.g., multiple scales). There is also a need to study the structure of secondary production models to understand under what conditions the models are stable and to understand the effect of forcing functions.