As the oil activity outside the Norwegian coast moves towards north, the potential for conflict with the fishing industry increases. Reasons for this are the presence of spawning areas for important fish stocks like herring and cod, and also the technical development of subsurface solutions for the oil exploration, increasing the risks for the occurrence of subsurface blowouts, The paper explains hom this potential for conflict can be described by means of numerical modelling techniques. The Haltenbanken area outside the western coast of Norway is selected as a field case, The modelling work involves underwater plume modelling as well as 3D modelling of ocean currents, The results front these modelling works are then combined with the modelling of the far-field transport and dilution of the underwater plume, and also the modelling of the spreading and transport of larvae from spawning areas. By combining the calculation of the concentration fields with the spreading calculations of the larvae, the exposure of a total larvae population (one year stock) can be estimated. The paper concludes that under unfavourable conditions, the overlap between the hydrocarbon concentration fields and the geographical distribution of larvae at its most vulnerable stage may cause a significant impact on a population level.