Bio-Physical Models of Oceanic Population Dynamics was the central theme of the 1994 summer program in Geophysical Fluid Dynamics (GFD) at the Woods Hole Oceanographic Institution. This unusual topic brought together mathematical population biologists and geophysical fluid dynamicists and provided a new synthesis of ideas and methods for coupling these two broad and diverse fields. Lectures and seminars given by staff and visitors addressed the nature of physical controls on free-drafting or active swimming organisms in the oceans, the biological responses of marine populations to their physical environment and their own internal states, and the dynamics of coupled biophysical processes on marine populations. This volume includes write-ups of the principal lectures, abstracts of some seminars, and the reports of the fellows' research projects.