Executive Summary
From 23-25 February 1993, twenty-one scientists from the physical and
biological community with expertise in modeling and empirical
observations, met in Savannah, GA for a U.S. GLOBEC sponsored workshop
on secondary production modeling. The goal of the workshop was to
assess the present state of secondary production modeling in the sea and
to provide recommendations for future research directions. Of
particular importance, the workshop identified several scientific areas
that are, perhaps, presently limiting advancement in the modeling of
zooplankton population dynamics and production.
Following nine overview presentations, the participants formed working
groups to discuss issues related to three of these scientific areas: 1)
animal behavior; 2) integration across scales and the linking of
information at different scales; and, 3) structural aspects of secondary
production models. The primary recommendations that resulted from these
working group discussions are to:
- Develop models that include our understanding of the mechanics
underlying animal behaviors, including proximal and ultimate
environmental factors controlling behavior.
- Develop nested models that encompass biological processes from the level
of the individual to the level of the population. Such models must
bridge a wide range of temporal and spatial scales, i.e., from the local
to the regional in space, and from the hourly to the annual in time.
- Develop detailed mechanistic models for a few key zooplankton species
that allow for the inclusion of inter-individual variability, including
genetics. These models need to consider more complex structural aspects
of the system that impact the key species, such as the dynamics of
primary producers and microzooplankton grazers, which represent much of
the prey resources for the larger zooplankton.
Besides these specific recommendations of the working groups, two
recurrent themes emerged from the plenary and working group discussions.
First, there was a consensus for the development of stronger ties
between empiricists and modelers at all scales. Scale considerations
include temporal, spatial, and ecological
(individuals to populations to ecosystems). Moreover, cooperation
between empiricists and modelers will become more important as
biological models move toward the development of fully data assimilative
models. Two way interactions are needed: empiricists need to consider
the, potentially unique, data requirements of the modelers-e.g., the
types of data, and their spatial and temporal frequency; modelers, on
the other hand, need to consider the observationalist's ability to
collect suitable data, and the empiricist's need for parameter
estimation. Second, it is desirable to make biological models,
especially models of zooplankton population dynamics, accessible to a
broader segment of the biological oceanographic community. This is
especially true for those models that couple the biological dynamics of
populations to the physics of the environment, particularly when more
than one dimension is included. U.S. GLOBEC should support the
development of a biological oceanography community model(s), similar to
those available for physical oceanography.