Publication Abstract

The implications of climate change for the management of North Sea cod (Gadus morhua)

L.T. Kell, G.M. Pilling and C.M. O’Brien

Mean annual sea surface temperature in the North Sea is projected to rise by over a degree centigrade by 2040. This is likely to affect the life history processes of cod (Gadus morhua). In this study, the influence of climate change on growth and recruitment of cod and the robustness of both short-term recovery and longer-term sustainable management strategies to different plausible climatic change scenarios are evaluated using a simulation framework. In the short term, climate change had little effect on recovery, since the increase in temperature is relatively small and most of the biomass increase comprises year classes that are recruited before the implementation of the recovery plan. Short-term recovery depends upon reducing fishing effort to allow cod to survive to mature and reproduce. In the longer-term, climate change has a greater effect on stock status. Although higher yields and biomass can be expected if fishing mortality is reduced. The consequences of climate change for fisheries management and biological reference points to define safe biological limits depends upon the mechanism upon which temperature acts, i.e. on juvenile survival or carrying capacity, although it is not possible to distinguish between these processes using stock assessment data sets alone.

Reference:

L.T. Kell, G.M. Pilling and C.M. O’Brien (2005) The implications of climate change for the management of North Sea cod (Gadus morhua). ICES Journal of Marine Science, 62: 1483-1491