Approaches to understanding transport of marine organisms

Population dynamics of marine organisms largely depend on transport of larvae, propagules and holoplankton. A number of factors influence their transport and multiple biological and geophysical processes are involved in various spatiotemporal scales. These processes and scales are often taxa specific, making it difficult to understand transport mechanisms as species-specific information may be required. Moreover, observing transport of such tiny planktonic organisms is challenging since they cannot be tagged and tracked effectively. Some techniques and methods were developed to describe transport mechanisms of the organisms over the last decades, and biological-physical coupling models are used more and more. The current status of our understanding of the transport processes and study methods will be discussed, and some results from recent research will be presented. For example, a coupled biophysical model showed that cross-shore transport of larvae and phytoplankton in the surf zone are controlled by wave/wind-driven currents, vertical positions of plankton, and bathymetric features. This result indicates that physical dynamics, biological traits, and geological characteristics are all important to understand plankton transport in coastal areas.