Modeling Of Cod Eggs And Larvae Drift, Growth And Survival In The Gulf Of St. Lawrence, Canada

No abstracts are to be cited without prior reference to the author.

Connectivity of stocks through eggs and larvae drift might be an important parameter influencing the recruitment of cod. Unfortunately, in many cases, the scarcity of observations precludes a detailed analysis of the drift and its variability. To address the issue, we developed a three-dimensional biophysical modelling system to hindcast oceanic conditions and the drift, growth and survival of the early life stages of cod in the Southern Gulf of St. Lawrence and Northeast Scotian Shelf (Canada). Individual-Based Models (IBM) of cod eggs and larvae are incorporated into a full 3-D hydrodynamic model of the ocean. All the data required to drive the model from 1950 to 2003 have been assembled. Specific indices of the drift, growth and survival are developed for fishing areas. The results show that there is strong year-to-year variability in the drift and survival of the larvae. Comparisons with snow crab larvae simulations show that the settlement patterns of the two species are different due to the timing of the spawning, the vertical distribution of the larvae and larval stage lengths.