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98> Chapter 055.2 > > Barren land,poor fishermen: Inthe Søndmør regionof western Norwaypeople’s livelihoodsused to dependalmost exclusivelyon fishing, andparticularly on thedevelopment of fishstocks.The offspring production of a fish stock is limited. If thespawning biomass is large, the habitat at some stagereaches its maximum carrying capacity. Even if thespawning biomass then continues to grow, the number ofjuvenile fish remains at a certain level. At this stage theamount of offspring depends entirely on the environmentalconditions. Various factors come into play here: eggsand larvae may be eaten by predators, for example, orstarve because insufficient food is available. In additionthere can be competition for suitable spawning sites todeposit eggs. The Baltic Sea herring, for example, depositsits adhesive eggs on aquatic plants. When there are toomany spawners, they deposit the eggs on top of eachother, and those underneath die from a lack of oxygen. Asthese conditions can fluctuate from year to year, so toodoes the number of offspring when spawning stocks arehigh. There can be strong but also very weak years foroffspring.If a stock is exploited too intensively the following canoccur. The spawning mass is at some stage so small thatfew offspring can be produced. In such a case the numberof offspring depends directly on the number of spawners.It is no longer capable of reaching its carrying capacity,even when good environmental conditions prevail. Thevalue at which the spawning biomass is so small is calledlimit biomass (B LIM). The corresponding fishing mortalityrate is described as F LIM.The failure of the precautionary approachThe massive overfishing of many stocks by the industrialfishing industry in the 1970s, 1980s and 1990s made theimportance of limiting catch volumes abundantly clear. In1995, the international community adopted a more cautiousapproach to fishing with the United Nations StraddlingFish Stocks Agreement (UNFSA). In the same year