Publication Abstract

Testing the match-mismatch hypothesis on North Atlantic cod stocks, using a 1-D zooplankton production model. (RS12)

Testing the match-mismatch hypothesis on North Atlantic cod stocks, using a 1-D zooplankton production model. (RS12)

K.M. Brander, R.R. Dickson and J.G. Shepherd

The match-mismatch hypothesis is difficult to test for a number of reasons, not least of which is lack of adequately resolved spatial and seasonal data for matching fish larvae and their food. The spatial, seasonal and interannual variability of water column stratification, primary production and copepod egg production can now be modelled in some detail (Prestidge, Harris and Taylor, 1995). The question is whether such models adequately represent features of interannual variability which affect survival of fish larvae?

Information on the timing and location of cod larvae concentrations for several cod stocks will be used to identify target areas for which long term hindcasts of plankton production will be made. The hindcasts are driven by hourly meteorological data, which generate variability in water column stratification. Such hindcasts have already been carried out for the Irish Sea for a 29 year period (Prestidge and Taylor, in press).

There is evidence that cod may be particularly susceptible to food limitation during the late larval stage (Cushing, 1984). The relationship between hindcast zooplankton production and indices of cod recruitment or pre-recruit mortality will be explored. The structural and parameter sensitivity of the model will be discussed.

Reference:

K.M. Brander, R.R. Dickson and J.G. Shepherd, 1997. Testing the match-mismatch hypothesis on North Atlantic cod stocks, using a 1-D zooplankton production model. (RS12). ICES International Symposium on the Role of the Physical and Biological Processes in the Recruitment Dynamics of Marine Populations.

K.M. Brander, R.R. Dickson* and J.G. Shepherd

ICES International Symposium on the Role of the Physical and Biological Processes in the Recruitment Dynamics of Marine Populations