Comparison of two periods of North Sea herring stock management: success, failure, and monetary value

At two points in the past (1970 and 1995), North Sea herring (Clupea harengus) abundance and catches have been in a similar situation: the stock had declined from an earlier high and reached a depleted state with a spawning-stock biomass of around 400 000 t, well below the agreed biomass limit reference point of 800 000 t. Catches were also similar at 600 000 t annually, and too high to be sustainable. A comparison of the scientific advice, the management actions, and their effects on population trends over the periods following these two critical years provides insight into important management issues. The benefits to the industry of the value of the cumulative catch resulting from successful management of this large stock have been proven to outweigh by far the costs of obtaining good management advice. The conclusion is that sound scientific information plays an important role when difficult management issues have to be confronted. However, there are other critical issues, such as the stakeholders' wish to preserve the stock at all costs and a management organization that has authority to take decisions.