| Calanus finmarchicus is a zooplankter that forms a critical part of the North Atlantic ecosystem, and provides a key link in the transfer of energy between trophic levels. The Labrador Sea contains a large population of Calanus finmarchicus, but existing data for the central and northern parts of this region are sparse. There are, as yet, few wintertime observations due to the difficulties of data collection. Modelling studies provide a useful method to assess ecological and oceanographic processes and can give insight into the spatial structure of populations. This study couples a biological model of Calanus finmarchicus with a circulation model of the Labrador Sea and its environs in an attempt to understand interactions between the physical oceanographic transport processes of the region and zooplankton behaviour, life-history and distribution. The study aims to produce a large-scale, comprehensive picture of the spatial distribution of Calanus finmarchicus in the Labrador Sea, along with an exploration of the timing of diapause, and an examination of transport processes and their effect on population sustainability. The modelled population structure matches reasonably well to temporal and spatial patterns in the Labrador Sea derived from available data sets. During an annual cycle, surface currents can cause a population to be advected onto shelf and slope regions from the deeper ocean. A latitudinally-dependent diapause emergence scheme with early emergence to the south of Newfoundland provides the best fit to data. |
